Cyperus difformis L.is a troublesome weed in paddy fields and has attracted attention due to its resistance to acetohydroxyacid synthase(AHAS)inhibitors.It was found that the amino acid mutation in AHAS was the primar...Cyperus difformis L.is a troublesome weed in paddy fields and has attracted attention due to its resistance to acetohydroxyacid synthase(AHAS)inhibitors.It was found that the amino acid mutation in AHAS was the primary cause for the resistance of Cyperus difformis.However,the effect of different mutations on AHAS function is not clear in Cyperus difformis.To confirm the effect of mutations on AHAS function,six biotypes were collected,including Pro197Arg,Pro197Ser,Pro197Leu,Asp376Glu,Trp574Leu and wild type,from Hunan,Anhui,Jiangxi and Jiangsu provinces,China and the function of AHAS was characterized.The AHAS in vitro inhibition assay results indicated that the mutations decreased the sensitivity of AHAS to pyrazosulfuron-ethyl,in which the I_(50)(the half maximal inhibitory concentration)of wild type AHAS was 0.04μmol L^(-1)and Asp376Glu,Pro197Leu,Pro197Arg,Pro197Ser and Trp574Leu mutations were 3.98,11.50,40.38,38.19 and 311.43μmol L^(-1),respectively.In the determination of enzyme kinetics parameters,the Km and the maximum reaction velocity(Vmax)of the wild type were 5.18 mmol L^(-1)and 0.12 nmol mg^(-1)min^(-1),respectively,and the Km values of AHAS with Asp376Glu,Trp574Leu,Pro197Leu and Pro197Ser mutations were 0.38-0.93 times of the wild type.The Km value of the Pro197Arg mutation was 1.14times of the wild type,and the Vmax values of the five mutations were 1.17-3.33-fold compared to the wild type.It was found that the mutations increased the affinity of AHAS to the substrate,except for the Pro197Arg mutation.At a concentration of 0.0032-100 mmol L^(-1)branched-chain amino acids(BCAAs),the sensitivity of the other four mutant AHAS biotypes to feedback inhibition decreased,except for the Pro197Arg mutation.This study elucidated the effect of different mutations on AHAS function in Cyperus difformis and provided ideas for further study of resistance development.展开更多
Treatment with metformin can lead to the recovery of pleiotropic biological activities after spinal cord injury.However,its effect on spinal cord injury in aged mice remains unclear.Considering the essential role of a...Treatment with metformin can lead to the recovery of pleiotropic biological activities after spinal cord injury.However,its effect on spinal cord injury in aged mice remains unclear.Considering the essential role of angiogenesis during the regeneration process,we hypothesized that metformin activates the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway in endothelial cells,thereby promoting microvascular regeneration in aged mice after spinal cord injury.In this study,we established young and aged mouse models of contusive spinal cord injury using a modified Allen method.We found that aging hindered the recovery of neurological function and the formation of blood vessels in the spinal cord.Treatment with metformin promoted spinal cord microvascular endothelial cell migration and blood vessel formation in vitro.Furthermore,intraperitoneal injection of metformin in an in vivo model promoted endothelial cell proliferation and increased the density of new blood vessels in the spinal cord,thereby improving neurological function.The role of metformin was reversed by compound C,an adenosine monophosphate-activated protein kinase inhibitor,both in vivo and in vitro,suggesting that the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway likely regulates metformin-mediated angiogenesis after spinal cord injury.These findings suggest that metformin promotes vascular regeneration in the injured spinal cord by activating the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway,thereby improving the neurological function of aged mice after spinal cord injury.展开更多
Dysfunction of neuronal nitric oxide synthase contributes to neurotoxicity,which triggers cell death in various neuropathological diseases,including epilepsy.Studies have shown that inhibition of neuronal nitric oxide...Dysfunction of neuronal nitric oxide synthase contributes to neurotoxicity,which triggers cell death in various neuropathological diseases,including epilepsy.Studies have shown that inhibition of neuronal nitric oxide synthase activity increases the epilepsy threshold,that is,has an anticonvulsant effect.However,the exact role and potential mechanism of neuronal nitric oxide synthase in seizures are still unclear.In this study,we performed RNA sequencing,functional enrichment analysis,and weighted gene coexpression network analysis of the hippocampus of tremor rats,a rat model of genetic epilepsy.We found damaged hippocampal mitochondria and abnormal succinate dehydrogenase level and Na+-K+-ATPase activity.In addition,we used a pilocarpine-induced N2a cell model to mimic epileptic injury.After application of neuronal nitric oxide synthase inhibitor 7-nitroindazole,changes in malondialdehyde,lactate dehydrogenase and superoxide dismutase,which are associated with oxidative stress,were reversed,and the increase in reactive oxygen species level was reversed by 7-nitroindazole or reactive oxygen species inhibitor N-acetylcysteine.Application of 7-nitroindazole or N-acetylcysteine downregulated the expression of caspase-3 and cytochrome c and reversed the apoptosis of epileptic cells.Furthermore,7-nitroindazole or N-acetylcysteine downregulated the abnormally high expression of NLRP3,gasdermin-D,interleukin-1βand interleukin-18.This indicated that 7-nitroindazole and N-acetylcysteine each reversed epileptic cell death.Taken together,our findings suggest that the neuronal nitric oxide synthase/reactive oxygen species pathway is involved in pyroptosis of epileptic cells,and inhibiting neuronal nitric oxide synthase activity or its induced oxidative stress may play a neuroprotective role in epilepsy.展开更多
Sucrose phosphate synthase(SPS)is a rate-limiting enzyme that works in conjunction with sucrose-6-phosphate phosphatase(SPP)for sucrose synthesis,and it plays an essential role in energy provisioning during growth and...Sucrose phosphate synthase(SPS)is a rate-limiting enzyme that works in conjunction with sucrose-6-phosphate phosphatase(SPP)for sucrose synthesis,and it plays an essential role in energy provisioning during growth and development in plants as well as improving fruit quality.However,studies on the systematic analysis and evolutionary pattern of the SPS gene family in apple are still lacking.In the present study,a total of seven MdSPS and four MdSPP genes were identified from the Malus domestica genome GDDH13 v1.1.The gene structures and their promoter cis-elements,protein conserved motifs,subcellular localizations,physiological functions and biochemical properties were analyzed.A chromosomal location and gene-duplication analysis demonstrated that whole-genome duplication(WGD)and segmental duplication played vital roles in MdSPS gene family expansion.The Ka/Ks ratio of pairwise MdSPS genes indicated that the members of this family have undergone strong purifying selection during domestication.Furthermore,three SPS gene subfamilies were classified based on phylogenetic relationships,and old gene duplications and significantly divergent evolutionary rates were observed among the SPS gene subfamilies.In addition,a major gene related to sucrose accumulation(MdSPSA2.3)was identified according to the highly consistent trends in the changes of its expression in four apple varieties(‘Golden Delicious’,‘Fuji’,‘Qinguan’and‘Honeycrisp’)and the correlation between gene expression and soluble sugar content during fruit development.Furthermore,the virus-induced silencing of MdSPSA2.3 confirmed its function in sucrose accumulation in apple fruit.The present study lays a theoretical foundation for better clarifying the biological functions of the MdSPS genes during apple fruit development.展开更多
Sesquiterpenes are the major pharmacodynamic components of agarwood,a precious traditional Chinese medicine obtained from the resinous portions of Aquilaria sinensis trees that form in response to environmental stress...Sesquiterpenes are the major pharmacodynamic components of agarwood,a precious traditional Chinese medicine obtained from the resinous portions of Aquilaria sinensis trees that form in response to environmental stressors.To characterize the sesquiterpene synthases responsible for sesquiterpene production in A.sinensis,a bioinformatics analysis of the genome of A.sinensis identifi ed six new terpene synthase genes,and 16 sesquiterpene synthase genes were identifi ed as type TPS-a in a phylogenetic analysis.The expression patterns for eight of the sesquiterpene synthase genes after treatment with various hormones or hydrogen peroxide were analyzed by real-time quantitative PCR.The results suggest that 100μM methyl jasmonate,ethephon,(±)-abscisic acid or hydrogen peroxide could be eff ective short-term eff ectors to increase the expression of sesquiterpene synthase genes,while 1 mM methyl salicylate may have long-term eff ects on increasing the expression of specifi c sesquiterpene synthase genes(e.g.,As-SesTPS,AsVS,AsTPS12 and AsTPS29).The expression changes in these genes under various conditions refl ected their specifi c roles during abiotic or biotic stresses.Heterologous expression of a novel A.sinensis sesquiterpene synthase gene,AsTPS2,in Escherichia coli produced a major humulene product,so AsTPS2 is renamed AsHS1.AsHS1 is diff erent from ASS1,AsSesTPS,and AsVS,for mainly producingα-humulene.Based on the predicted space conformation of the AsHS1 model,the small ligand molecule may bind to the free amino acid by hydrogen bonding for the catalytic function of the enzyme,while the substrate farnesyl diphosphate(FPP)probably binds to the free amino acid on one side of the RxR motif.Arg450,Asp453,Asp454,Thr457,and Glu461 from the NSE/DTE motif and D307 and D311 from the DDxxD motif were found to form a polar interaction with two Mg^(2+)clusters by docking.The Mg^(2+)-bound DDxxD and NSE/DTE motifs and the free RXR motif are jointly directed into the catalytic pocket of AsHS1.Comparison of the tertiary structural models of AsHS1 with ASS1 showed that they diff ered in structures in several positions,such as surrounding the secondary catalytic pocket,which may lead to diff erences in catalytic products.Based on the results,biosynthetic pathways for specifi c sesquiterpenes such asα-humulene in A.sinensis are proposed.This study provides novel insights into the functions of the sesquiterpene synthases of A.sinensis and enriches knowledge on agarwood formation.展开更多
Objective:To determine the genetic diversity,natural selection and mutations in Plasmodium(P.)knowlesi drug resistant molecular markers Kelch 13 and dhps gene in clinical samples of Malaysia.Methods:P.knowlesi full-le...Objective:To determine the genetic diversity,natural selection and mutations in Plasmodium(P.)knowlesi drug resistant molecular markers Kelch 13 and dhps gene in clinical samples of Malaysia.Methods:P.knowlesi full-length gene sequences Kelch 13 gene(PkK13)from 40 samples and dhps gene from 30 samples originating from Malaysian Borneo were retrieved from public databases.Genetic diversity,natural selection,and phylogenetic analysis of gene sequences were analysed using DNAsp v5.10 and MEGA v5.2.Results:Seventy-two single nucleotide polymorphic sites(SNPs)across the full-length PkK13 gene(63 synonymous substitutions and 9 non-synonymous substitutions)with nucleotide diversity ofπ~0.005 was observed.Analysis of the full-length Pkdhps gene revealed 73 SNPs andπ~0.006(44 synonymous substitutions and 29 non-synonymous substitutions).A high number of haplotypes(PkK13;H=37 and Pkdhps;H=29)with haplotype diversity of Hd~0.99 were found in both genes,indicating population expansion.Nine mutant alleles were identified in PkK13 amino acid alignment of which,7(Asp3Glu,Lys50Gln,Lys53Glu,Ser123Thr,Ser127Pro,Ser149Thr and Ala169Thr)were within the Plasmodium specific domain,2(Val372Ile and Lys424Asn)were in the BTB/POZ domain and no mutation was observed within the kelch propeller domain.The 29 non-synonymous mutations in the Pkdhps gene were novel and only presented in exon 1 and 2.Conclusions:Monitoring the mutations from clinical samples collected from all states of Malaysia along with clinical efficacy studies will be necessary to determine the drug resistance in P.knowlesi.展开更多
Neuronal nitric oxide synthase(nNOS)was the producer of nitric oxide(NO)which played important gas messenger molecules in biological process.It also can take effect as immune regulation molecule in organism.Black rock...Neuronal nitric oxide synthase(nNOS)was the producer of nitric oxide(NO)which played important gas messenger molecules in biological process.It also can take effect as immune regulation molecule in organism.Black rockfish(Sebastes schlegelii)is an important economic fish which were widely farmed in East Asia countries.Meanwhile,the pathogenic bacteria such as the Edwardsiella tarda and Vibrio anguillarum in seawater always brought serious obstacles to their healthy growth.In order to explore the expression pattern of n NOS gene under the pathogen stimulation and predict its immune function,the n NOS gene in black rockfish named Ssn NOS was identified.It was 3780 bp in length,located on chromosome 6,and contained 27 coding domain sequence(CDs).According to the phylogenetic analysis,the Ssn NOS showed closest relative to the counterpart gene of swamp eel(Monopterus albus).Meanwhile,analysis of Ssn NOS expression in various healthy tissues showed that Ssn NOS expression level was highest in healthy brain tissues,followed by intestinal tissues.In addition,Ssn NOS showed significant expression changes in response to stimulation by two pathogens.Particular in gill,the expression of Ssn NOS after pathogenic stimulation increased significantly.The Elisa analysis showed the Ssn NOS content in gills was much higher than that in other tissues at all time points.Moreover,the expression patterns of Ssn NOS in brain,intestine and kidney after stimulation by pathogens showed a distinct expression pattern which first down-regulated and then up-regulated.Therefore,the Ssn NOS may be an important signaling molecule for fish to respond rapidly in immune stimulation.展开更多
Callose contributes to many biological processes of higher plants including pollen development,cell plate and vascular tissue formation,as well as regulating the transport function of plasmodesmata.The functions of ca...Callose contributes to many biological processes of higher plants including pollen development,cell plate and vascular tissue formation,as well as regulating the transport function of plasmodesmata.The functions of callose synthase genes in maize have been little studied.We describe a maize male-sterile mutant 39(ms39)characterized by reduced plant height.In this study,we confirmed using CRISPR/Cas9 technology that a mutation in Zm00001d043909(ZmCals12),encoding a callose synthase,is responsible for the male sterility of the ms39 mutant.Compared with male-fertile plants,callose deposition around the dyads and tetrads in ms39 anthers was significantly reduced.Increased cell autophagy observed in ms39 anthers may have been due to the premature programmed cell death of tapetal cells,leading to collapse of the anther wall structure.Disordered glucose metabolism in ms39 may have intensified autophagy in anthers.Evaluation of the ms39 gene on maize heterosis by paired-crossed experiment with 11 maize inbred lines indicated that ms39 can be used for maize hybrid seed production.展开更多
BACKGROUND Oxaliplatin(Oxa)is the first-line chemotherapy drug for colorectal cancer(CRC),and Oxa resistance is crucial for treatment failure.Prostaglandin F_(2α)synthase(PGF 2α)(PGFS),an enzyme that catalyzes the p...BACKGROUND Oxaliplatin(Oxa)is the first-line chemotherapy drug for colorectal cancer(CRC),and Oxa resistance is crucial for treatment failure.Prostaglandin F_(2α)synthase(PGF 2α)(PGFS),an enzyme that catalyzes the production of PGF_(2α),is involved in the proliferation and growth of a variety of tumors.However,the role of PGFS in Oxa resistance in CRC remains unclear.AIM To explore the role and related mechanisms of PGFS in mediating Oxa resistance in CRC.METHODS The PGFS expression level was examined in 37 pairs of CRC tissues and paracancerous tissues at both the mRNA and protein levels.Overexpression or knockdown of PGFS was performed in CRC cell lines with acquired Oxa resistance(HCT116-OxR and HCT8-OxR)and their parental cell lines(HCT116 and HCT8)to assess its influence on cell proliferation,chemoresistance,apoptosis,and DNA damage.For determination of the underlying mechanisms,CRC cells were examined for platinum-DNA adducts and reactive oxygen species(ROS)levels in the presence of a PGFS inhibitor or its products.RESULTS Both the protein and mRNA levels of PGFS were increased in the 37 examined CRC tissues compared to the adjacent normal tissues.Oxa induced PGFS expression in the parental HCT116 and HCT8 cells in a dosedependent manner.Furthermore,overexpression of PGFS in parental CRC cells significantly attenuated Oxainduced proliferative suppression,apoptosis,and DNA damage.In contrast,knockdown of PGFS in Oxa-resistant HCT116 and HCT8 cells(HCT116-OxR and HCT8-OxR)accentuated the effect of Oxa treatment in vitro and in vivo.The addition of the PGFS inhibitor indomethacin enhanced the cytotoxicity caused by Oxa.Treatment with the PGFS-catalyzed product PGF_(2α)reversed the effect of PGFS knockdown on Oxa sensitivity.Interestingly,PGFS inhibited the formation of platinum-DNA adducts in a PGF_(2α)-independent manner.PGF_(2α)exerts its protective effect against DNA damage by reducing ROS levels.CONCLUSION PGFS promotes resistance to Oxa in CRC via both PGF_(2α)-dependent and PGF_(2α)-independent mechanisms.展开更多
Background Herbicide tolerance in crops enables them to survive when lethal doses of herbicides are applied to surrounding weeds.Herbicide-tolerant crops can be developed through transgenic approaches or traditional m...Background Herbicide tolerance in crops enables them to survive when lethal doses of herbicides are applied to surrounding weeds.Herbicide-tolerant crops can be developed through transgenic approaches or traditional mutagenesis approaches.At present,no transgenic herbicide tolerant cotton have been commercialized in China due to the genetically-modified organism(GMO)regulation law.We aim to develop a non-transgenic herbicide-tolerant cotton through ethyl methanesulfonate(EMS)mutagenesis,offering an alternative choice for weed management.Results Seeds of an elite cotton cultivar Lumianyan 37(Lu37)were treated with EMS,and a mutant Lu37-1 showed strong tolerance to imidazolinone(IMI)herbicides was identified.A novel nonsynonymous substitution mutation Ser642Asn at acetolactate synthase(ALS)(Gh_D10G1253)in Lu37-1 mutant line was found to be the potential cause to the IMI herbicides tolerance in cotton.The Ser642Asn mutation in ALS did not present among the genomes of natural Gossypium species.Cleaved amplified polymorphic sequence(CAPS)markers were developed to identify the ALS mutant allele.The Arabidopsis overexpressing the mutanted ALS also showed high tolerance to IMI herbicides.Conclusion The nonsynonymous substitution mutation Ser642Asn of the ALS gene Gh_D10G1253 is a novel identi-fied mutation in cotton.This substitution mutation has also been identified in the orthologous ALS genes in other crops.This mutant ALS allele can be used to develop IMI herbicide-tolerant crops via a non-transgenic or transgenic approach.展开更多
Alzheimer’s disease (AD) is the most prevalent cause of dementia worldwide. Because of the progressive neurodegeneration, individual cognitive and behavioral functions are impaired, affecting the quality of life of m...Alzheimer’s disease (AD) is the most prevalent cause of dementia worldwide. Because of the progressive neurodegeneration, individual cognitive and behavioral functions are impaired, affecting the quality of life of millions of people. Although the exact pathogenesis of AD has not been fully elucidated, amyloid plaques, neurofibrillary tangles (NFTs), and sustaining neuroinflammation dominate its characteristics. As one of the major tau kinases leading to hyperphosphorylation and aggregation of tau, glycogen synthase kinase-3β (GSK-3β) has been drawing great attention in various AD studies. Another research focus of AD in recent years is the inflammasome, a multiprotein complex acting as a regulator in immunological reactions to exogenous and endogenous danger signals, of which the Nod-like receptor (NLR) family, pyrin domain-containing 3 (NLRP3) inflammasome has been studied mostly in AD and proven to play a significant role in AD development by its activation and downstream effects such as caspase-1 maturation and interleukin (IL)-1β release. Studies have shown that the NLRP3 inflammasome is activated in a GSK-3β-dependent way and that inhibition of the NLRP3 inflammasome downregulates GSK-3β, suggesting that these two important proteins are closely related. This article reviews the respective roles of GSK-3β and the NLRP3 inflammasome in AD as well as their relationship and interaction.展开更多
BACKGROUND Clinical prognosis often worsens due to high recurrence rates following radical surgery for colon cancer.The examination of high-risk recurrence factors post-surgery provides critical insights for disease e...BACKGROUND Clinical prognosis often worsens due to high recurrence rates following radical surgery for colon cancer.The examination of high-risk recurrence factors post-surgery provides critical insights for disease evaluation and treatment planning.AIM To explore the relationship between metastasis-associated factor-1 in colon cancer(MACC1)and vacuolar ATP synthase(V-ATPase)expression in colon cancer tissues,and recurrence rate in patients undergoing radical colon cancer surgery.METHODS We selected 104 patients treated with radical colon cancer surgery at our hospital from January 2018 to June 2021.Immunohistochemical staining was utilized to assess the expression levels of MACC1 and V-ATPase in these patients.RESULTS The rates of MACC1 and V-ATPase positivity were 64.42%and 67.31%,respe-ctively,in colon cancer tissues,which were significantly higher than in paracan-cerous tissues(P<0.05).Among patients with TNM stage III,medium to low differentiation,and lymph node metastasis,the positive rates of MACC1 and V-ATPase were significantly elevated in comparison to patients with TNM stage I-II,high differentiation,and no lymph node metastasis(P<0.05).The rate of MACC1 positivity was 76.67%in patients with tumor diameters>5 cm,notably higher than in patients with tumor diameters≤5 cm(P<0.05).We observed a positive correlation between MACC1 and V-ATPase expression(rs=0.797,P<0.05).The positive rates of MACC1 and V-ATPase were significantly higher in patients with recurrence compared to those without(P<0.05).Logistic regression analysis revealed TNM stage,lymph node metastasis,MACC1 expression,and V-ATPase expression as risk factors for postoperative colon cancer recurrence(OR=6.322,3.435,2.683,and 2.421;P<0.05).CONCLUSION The upregulated expression of MACC1 and V-ATPase in colon cancer patients appears to correlate with clinicopathological features and post-radical surgery recurrence.展开更多
AIM: To study the distribution of nitric oxide synthase (NOS) in rat stomach myenteric plexus.METHODS: The distribution of NOS in gastric wall was studied in quantity and location by the NADPH-diaphorase (NDP) histo...AIM: To study the distribution of nitric oxide synthase (NOS) in rat stomach myenteric plexus.METHODS: The distribution of NOS in gastric wall was studied in quantity and location by the NADPH-diaphorase (NDP) histochemical staining method and whole mount preparation technique.RESULTS: NOS was distributed in whole stomach wall, most of them were located in myenteric plexus, and distributed in submucosal plexus. The shape of NOS positive neurons was basically similar, most of them being round and oval in shape. But their density, size and staining intensity varied greatly in the different parts of stomach. The density was 62 -± 38 cells/mm2(antrum), 43 ± 32 cells/mm2(body), and 32 ± 28 cells/mm2 (fundus), respectively. The size and staining intensity of NOS positive neurons in the fundus were basically the same, the neurons being large and dark stained, while they were obviously different in antrum. In the body of the stomach, the NOS positive neurons were in an intermediate state from fundus to antrum. There were some beadlike structures which were strung together by NOS positive varicosities in nerve fibers, some were closely adherent to the outer walls of blood vessels.CONCLUSION: Nitric oxide might he involved in the modulation of motility, secretion and blood ciroulation of the stomach, and the significant difference of NOS positive neurons in different parts of stomach myenteric plexus may be related to the physiologic function of stomach.展开更多
INTRODUCTIONThe treatment of human epithelial malignancies islimited by drug resistance and toxic and side effects,which results in the failure in the treatment ofmajority of advanced cancer victims.To seek for anew,a...INTRODUCTIONThe treatment of human epithelial malignancies islimited by drug resistance and toxic and side effects,which results in the failure in the treatment ofmajority of advanced cancer victims.To seek for anew,and specific antineoplastic therapy willprovide hope for tumor treatment.Althoughdisordered intermediary metabolism in cancer cellshas been known for many years,much of the展开更多
Sucrose synthases(SUS) are a family of enzymes that play pivotal roles in carbon partitioning, sink strength and plant development. A total of 11 SUS genes have been identified in the genome of Malus domestica(Md SUSs...Sucrose synthases(SUS) are a family of enzymes that play pivotal roles in carbon partitioning, sink strength and plant development. A total of 11 SUS genes have been identified in the genome of Malus domestica(Md SUSs), and phylogenetic analysis revealed that the Md SUS genes were divided into three groups, named as SUS I, SUS II and SUS III, respectively. The SUS I and SUS III groups included four homologs each, whereas the SUS II group contained three homologs. SUS genes in the same group showed similar structural characteristics, such as exon number, size and length distribution. After assessing four different tissues, Md SUS1 s and Md SUS2.1 showed the highest expression in fruit, whereas Md SUS2.2/2.3 and Md SUS3 s exhibit the highest expression in shoot tips. Most Md SUSs showed decreased expression during fruit development, similar to SUS enzyme activity, but both Md SUS2.1 and Md SUS1.4 displayed opposite expression profiles. These results suggest that different Md SUS genes might play distinct roles in the sink-source sugar cycle and sugar utilization in apple sink tissues.展开更多
Aphids are major agricultural pests that cause significant yield losses in crop plants each year.(E)-β-farnesene(EβF) is the main or only component of an alarm pheromone involved in chemical communication within aph...Aphids are major agricultural pests that cause significant yield losses in crop plants each year.(E)-β-farnesene(EβF) is the main or only component of an alarm pheromone involved in chemical communication within aphid species and particularly in the avoidance of predation. EβF also occurs in the essential oil of some plant species, and is catalyzed by EβF synthase. By using oligonucleotide primers designed from the known sequence of an EβF synthase gene from black peppermint(Mentha × piperita), two cDNA sequences, MaβFS1 and MaβFS2, were isolated from Asian peppermint(Mentha asiatica). Expression pattern analysis showed that the MaβFS1 gene exhibited higher expression in flowers than in roots, stems and leaves at the transcriptional level. Overexpression of MaβFS1 in tobacco plants resulted in emission of pure EβF ranging from 2.62 to 4.85 ng d-1g-1of fresh tissue. Tritrophic interactions involving peach aphids(Myzus persicae), and predatory lacewing(Chrysopa septempunctata) larvae demonstrated that transgenic tobacco expressing MaβFS1 had lower aphid infestation. This result suggested that the EβF synthase gene from Asian peppermint could be a good candidate for genetic engineering of agriculturally important crop plants.展开更多
An efficient and simple method for constructing a genomic DNA library using a TAcloning vector is presented. It is based on the sonicative cleavage of genomic DNA and modification offragment ends with Taq DNA polymera...An efficient and simple method for constructing a genomic DNA library using a TAcloning vector is presented. It is based on the sonicative cleavage of genomic DNA and modification offragment ends with Taq DNA polymerase, followed by ligation using a TA vector. This method was ap-plied for cloning of the phytoene synthase gene crtB from Spirulina platensis. This method is useful whengenomic DNA cannot be efficiently digested with restriction enzymes, a problem often encountered duringthe construction of a genomic DNA library of cyanobacteria.展开更多
The biosynthesis of prostanoids is involved in both physiological and pathological processes. The expression of prostaglandin-endoperoxide synthase 2(PTGS2; also known as COX-2) has been traditionally associated to th...The biosynthesis of prostanoids is involved in both physiological and pathological processes. The expression of prostaglandin-endoperoxide synthase 2(PTGS2; also known as COX-2) has been traditionally associated to the onset of several pathologies, from inflammation to cardiovascular, gastrointestinal and oncologic events. For this reason, the search of selective PTGS2 inhibitors has been a focus for therapeutic interventions. In addition to the classic non-steroidal anti-inflammatory drugs, selective and specific PTGS2 inhibitors, termed coxibs, have been generated and widely used. PTGS2 activity is less restrictive in terms of substrate specificity than the homeostatic counterpart PTGS1, and it accounts for the elevated prostanoid synthesis that accompanies several pathologies. The main regulation of PTGS2 occurs at the transcription level. In addition to this, the stability of the mRNA is finely regulated through the interaction with several cytoplasmic elements, ranging from specificmicroR NAs to proteins that control mR NA degradation. Moreover, the protein has been recognized to be the substrate for several post-translational modifications that affect both the enzyme activity and the targeting for degradation via proteasomal and non-proteasomal mechanisms. Among these modifications, phosphorylation, glycosylation and covalent modifications by reactive lipidic intermediates and by free radicals associated to the proinflammatory condition appear to be the main changes. Identification of these post-translational modifications is relevant to better understand the role of PTGS2 in several pathologies and to establish a correct analysis of the potential function of this protein in diseases progress. Finally, these modifications can be used as biomarkers to establish correlations with other parameters, including the immunomodulation dependent on molecular pathological epidemiology determinants, which may provide a better frame for potential therapeutic interventions.展开更多
BACKGROUND:Nitric oxide(NO)and prostacyclin(PGI2) are both powerful vasoactive substances correlated with the hyperhemodynamics of portal hypertension(PHT), a common syndrome characterized by a pathological increase i...BACKGROUND:Nitric oxide(NO)and prostacyclin(PGI2) are both powerful vasoactive substances correlated with the hyperhemodynamics of portal hypertension(PHT), a common syndrome characterized by a pathological increase in portal venous pressure.The purpose of the present study was to evaluate the possible interaction between these two endothelial vasodilators,together with their respective roles in the hyperdynamic splanchnic circulation of PHT. METHODS:Ninety-six male Sprague-Dawley rats were randomly divided into three groups:intrahepatic portal hypertension(IHPH)induced by injection of CCl4(n=31), prehepatic portal hypertension(PHPH)induced by partial stenosis of the portal vein(n=33),and sham-operated controls(SO)(n=32).Animals of each group received indomethacin(INDO),a cyclooxygenase(COX)inhibitor, either short-term(7 days)or long-term(15 days),with saline as control.Free portal pressure(FPP),together with the concentration of NO and PGI2 in serum were measured.The activity of constitutive nitric oxide synthase (cNOS)and inducible nitric oxide synthase(iNOS)in the abdominal aorta and small intestine were determined by spectrophotometry.RT-PCR was performed to measure the levels of cNOS and iNOS mRNA in the arteries and small intestines. RESULTS:Compared with SO rats,the concentrations of NO and PGI2 in PHT rats were elevated,which were consistent with the increased FPP(P<0.05).Although administration of INDO persistently decreased the concentration of PGI2 in serum(P<0.05),the long-term INDO-treated IHPHand PHPH groups had restored splanchnic hyperdynamic circulation,demonstrated by the enhanced FPP(P<0.05). Furthermore,the changes of dynamic circulatory state in both IHPH and PHPH rats were concomitant with the expression and activity of iNOS and the concentration of NO(P<0.05).Although the expression and activity of cNOS in abdominal aorta of PHT rats were higher than in SO rats (P<0.05),there was no difference in small intestinal tissues between PHT and SO rats(P>0.05).Moreover,the changes of iNOS activity and mRNA expression were more marked than cNOS in PHT rats,and there was no difference in expression and activity of cNOS between PHT rats treated by short-and long-term INDO(P>0.05). CONCLUSIONS:iNOS plays an important role in the hemodynamic abnormalities of PHT induced by overproduction of NO.There is a possible interaction between PGI2 and NO in hyperhemodynamics of PHT, but PGI2 may not be a mediator in the formation and development of the hyperdynamic circulatory state in PHT rats.展开更多
基金funded by the National Natural Science Foundation of China(31972281)。
文摘Cyperus difformis L.is a troublesome weed in paddy fields and has attracted attention due to its resistance to acetohydroxyacid synthase(AHAS)inhibitors.It was found that the amino acid mutation in AHAS was the primary cause for the resistance of Cyperus difformis.However,the effect of different mutations on AHAS function is not clear in Cyperus difformis.To confirm the effect of mutations on AHAS function,six biotypes were collected,including Pro197Arg,Pro197Ser,Pro197Leu,Asp376Glu,Trp574Leu and wild type,from Hunan,Anhui,Jiangxi and Jiangsu provinces,China and the function of AHAS was characterized.The AHAS in vitro inhibition assay results indicated that the mutations decreased the sensitivity of AHAS to pyrazosulfuron-ethyl,in which the I_(50)(the half maximal inhibitory concentration)of wild type AHAS was 0.04μmol L^(-1)and Asp376Glu,Pro197Leu,Pro197Arg,Pro197Ser and Trp574Leu mutations were 3.98,11.50,40.38,38.19 and 311.43μmol L^(-1),respectively.In the determination of enzyme kinetics parameters,the Km and the maximum reaction velocity(Vmax)of the wild type were 5.18 mmol L^(-1)and 0.12 nmol mg^(-1)min^(-1),respectively,and the Km values of AHAS with Asp376Glu,Trp574Leu,Pro197Leu and Pro197Ser mutations were 0.38-0.93 times of the wild type.The Km value of the Pro197Arg mutation was 1.14times of the wild type,and the Vmax values of the five mutations were 1.17-3.33-fold compared to the wild type.It was found that the mutations increased the affinity of AHAS to the substrate,except for the Pro197Arg mutation.At a concentration of 0.0032-100 mmol L^(-1)branched-chain amino acids(BCAAs),the sensitivity of the other four mutant AHAS biotypes to feedback inhibition decreased,except for the Pro197Arg mutation.This study elucidated the effect of different mutations on AHAS function in Cyperus difformis and provided ideas for further study of resistance development.
基金supported by the Natural Nature Science Foundation of China,Nos.82030071,81874004the Science and Technology Major Project of Changsha,No.kh2103008(all to JZH).
文摘Treatment with metformin can lead to the recovery of pleiotropic biological activities after spinal cord injury.However,its effect on spinal cord injury in aged mice remains unclear.Considering the essential role of angiogenesis during the regeneration process,we hypothesized that metformin activates the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway in endothelial cells,thereby promoting microvascular regeneration in aged mice after spinal cord injury.In this study,we established young and aged mouse models of contusive spinal cord injury using a modified Allen method.We found that aging hindered the recovery of neurological function and the formation of blood vessels in the spinal cord.Treatment with metformin promoted spinal cord microvascular endothelial cell migration and blood vessel formation in vitro.Furthermore,intraperitoneal injection of metformin in an in vivo model promoted endothelial cell proliferation and increased the density of new blood vessels in the spinal cord,thereby improving neurological function.The role of metformin was reversed by compound C,an adenosine monophosphate-activated protein kinase inhibitor,both in vivo and in vitro,suggesting that the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway likely regulates metformin-mediated angiogenesis after spinal cord injury.These findings suggest that metformin promotes vascular regeneration in the injured spinal cord by activating the adenosine monophosphate-activated protein kinase/endothelial nitric oxide synthase pathway,thereby improving the neurological function of aged mice after spinal cord injury.
基金supported by the Natural Science Foundation of ChinaNos.81971212 (to FG)+7 种基金81601129 (to XXX)the Open Fund of the Key Laboratory of Medical ElectrophysiologyMinistry of Education&Medical Electrophysiological Key Laboratory of Sichuan ProvinceInstitute of Cardiovascular ResearchSouthwest Medical UniversityNo.KeyME-2018-07 (to FG)Liaoning Province Xingliao Talent Program ProjectNo.XLYC1907164 (to FG)
文摘Dysfunction of neuronal nitric oxide synthase contributes to neurotoxicity,which triggers cell death in various neuropathological diseases,including epilepsy.Studies have shown that inhibition of neuronal nitric oxide synthase activity increases the epilepsy threshold,that is,has an anticonvulsant effect.However,the exact role and potential mechanism of neuronal nitric oxide synthase in seizures are still unclear.In this study,we performed RNA sequencing,functional enrichment analysis,and weighted gene coexpression network analysis of the hippocampus of tremor rats,a rat model of genetic epilepsy.We found damaged hippocampal mitochondria and abnormal succinate dehydrogenase level and Na+-K+-ATPase activity.In addition,we used a pilocarpine-induced N2a cell model to mimic epileptic injury.After application of neuronal nitric oxide synthase inhibitor 7-nitroindazole,changes in malondialdehyde,lactate dehydrogenase and superoxide dismutase,which are associated with oxidative stress,were reversed,and the increase in reactive oxygen species level was reversed by 7-nitroindazole or reactive oxygen species inhibitor N-acetylcysteine.Application of 7-nitroindazole or N-acetylcysteine downregulated the expression of caspase-3 and cytochrome c and reversed the apoptosis of epileptic cells.Furthermore,7-nitroindazole or N-acetylcysteine downregulated the abnormally high expression of NLRP3,gasdermin-D,interleukin-1βand interleukin-18.This indicated that 7-nitroindazole and N-acetylcysteine each reversed epileptic cell death.Taken together,our findings suggest that the neuronal nitric oxide synthase/reactive oxygen species pathway is involved in pyroptosis of epileptic cells,and inhibiting neuronal nitric oxide synthase activity or its induced oxidative stress may play a neuroprotective role in epilepsy.
基金supported by the National Natural Science Foundation of China (32172521)the Excellent Youth Science Foundation of Heilongjiang Province,China (YQ2023C006)+1 种基金the Talent Introduction Program of Northeast Agricultural University of Chinathe Collaborative Innovation System of the Agricultural Bio-economy in Heilongjiang Province,China
文摘Sucrose phosphate synthase(SPS)is a rate-limiting enzyme that works in conjunction with sucrose-6-phosphate phosphatase(SPP)for sucrose synthesis,and it plays an essential role in energy provisioning during growth and development in plants as well as improving fruit quality.However,studies on the systematic analysis and evolutionary pattern of the SPS gene family in apple are still lacking.In the present study,a total of seven MdSPS and four MdSPP genes were identified from the Malus domestica genome GDDH13 v1.1.The gene structures and their promoter cis-elements,protein conserved motifs,subcellular localizations,physiological functions and biochemical properties were analyzed.A chromosomal location and gene-duplication analysis demonstrated that whole-genome duplication(WGD)and segmental duplication played vital roles in MdSPS gene family expansion.The Ka/Ks ratio of pairwise MdSPS genes indicated that the members of this family have undergone strong purifying selection during domestication.Furthermore,three SPS gene subfamilies were classified based on phylogenetic relationships,and old gene duplications and significantly divergent evolutionary rates were observed among the SPS gene subfamilies.In addition,a major gene related to sucrose accumulation(MdSPSA2.3)was identified according to the highly consistent trends in the changes of its expression in four apple varieties(‘Golden Delicious’,‘Fuji’,‘Qinguan’and‘Honeycrisp’)and the correlation between gene expression and soluble sugar content during fruit development.Furthermore,the virus-induced silencing of MdSPSA2.3 confirmed its function in sucrose accumulation in apple fruit.The present study lays a theoretical foundation for better clarifying the biological functions of the MdSPS genes during apple fruit development.
基金supported by the National Natural Science Foundation of China(81773844).
文摘Sesquiterpenes are the major pharmacodynamic components of agarwood,a precious traditional Chinese medicine obtained from the resinous portions of Aquilaria sinensis trees that form in response to environmental stressors.To characterize the sesquiterpene synthases responsible for sesquiterpene production in A.sinensis,a bioinformatics analysis of the genome of A.sinensis identifi ed six new terpene synthase genes,and 16 sesquiterpene synthase genes were identifi ed as type TPS-a in a phylogenetic analysis.The expression patterns for eight of the sesquiterpene synthase genes after treatment with various hormones or hydrogen peroxide were analyzed by real-time quantitative PCR.The results suggest that 100μM methyl jasmonate,ethephon,(±)-abscisic acid or hydrogen peroxide could be eff ective short-term eff ectors to increase the expression of sesquiterpene synthase genes,while 1 mM methyl salicylate may have long-term eff ects on increasing the expression of specifi c sesquiterpene synthase genes(e.g.,As-SesTPS,AsVS,AsTPS12 and AsTPS29).The expression changes in these genes under various conditions refl ected their specifi c roles during abiotic or biotic stresses.Heterologous expression of a novel A.sinensis sesquiterpene synthase gene,AsTPS2,in Escherichia coli produced a major humulene product,so AsTPS2 is renamed AsHS1.AsHS1 is diff erent from ASS1,AsSesTPS,and AsVS,for mainly producingα-humulene.Based on the predicted space conformation of the AsHS1 model,the small ligand molecule may bind to the free amino acid by hydrogen bonding for the catalytic function of the enzyme,while the substrate farnesyl diphosphate(FPP)probably binds to the free amino acid on one side of the RxR motif.Arg450,Asp453,Asp454,Thr457,and Glu461 from the NSE/DTE motif and D307 and D311 from the DDxxD motif were found to form a polar interaction with two Mg^(2+)clusters by docking.The Mg^(2+)-bound DDxxD and NSE/DTE motifs and the free RXR motif are jointly directed into the catalytic pocket of AsHS1.Comparison of the tertiary structural models of AsHS1 with ASS1 showed that they diff ered in structures in several positions,such as surrounding the secondary catalytic pocket,which may lead to diff erences in catalytic products.Based on the results,biosynthetic pathways for specifi c sesquiterpenes such asα-humulene in A.sinensis are proposed.This study provides novel insights into the functions of the sesquiterpene synthases of A.sinensis and enriches knowledge on agarwood formation.
基金supported by the institutional funding committee of Najran University,Najran,Saudi Arabia(Project code:NU/IFC/ENT/01/007).
文摘Objective:To determine the genetic diversity,natural selection and mutations in Plasmodium(P.)knowlesi drug resistant molecular markers Kelch 13 and dhps gene in clinical samples of Malaysia.Methods:P.knowlesi full-length gene sequences Kelch 13 gene(PkK13)from 40 samples and dhps gene from 30 samples originating from Malaysian Borneo were retrieved from public databases.Genetic diversity,natural selection,and phylogenetic analysis of gene sequences were analysed using DNAsp v5.10 and MEGA v5.2.Results:Seventy-two single nucleotide polymorphic sites(SNPs)across the full-length PkK13 gene(63 synonymous substitutions and 9 non-synonymous substitutions)with nucleotide diversity ofπ~0.005 was observed.Analysis of the full-length Pkdhps gene revealed 73 SNPs andπ~0.006(44 synonymous substitutions and 29 non-synonymous substitutions).A high number of haplotypes(PkK13;H=37 and Pkdhps;H=29)with haplotype diversity of Hd~0.99 were found in both genes,indicating population expansion.Nine mutant alleles were identified in PkK13 amino acid alignment of which,7(Asp3Glu,Lys50Gln,Lys53Glu,Ser123Thr,Ser127Pro,Ser149Thr and Ala169Thr)were within the Plasmodium specific domain,2(Val372Ile and Lys424Asn)were in the BTB/POZ domain and no mutation was observed within the kelch propeller domain.The 29 non-synonymous mutations in the Pkdhps gene were novel and only presented in exon 1 and 2.Conclusions:Monitoring the mutations from clinical samples collected from all states of Malaysia along with clinical efficacy studies will be necessary to determine the drug resistance in P.knowlesi.
基金supported by the Natural Science Foundation of Shandong Province(No.ZR2020QC214)the Young Experts of Taishan Scholars(No.tsqn201909130)+3 种基金the Science and Technology Support Plan for Youth Innovation of Colleges and Universities in Shandong Province(No.2019KJF003)the‘First Class Fishery Discipline’Programme in Shandong Provincea special talent programme‘One Thing One Decision(YishiYiyi)’Programme in Shandong Province,Chinathe Breeding Plan of Shandong Provincial Qingchuang Research Team(2019)。
文摘Neuronal nitric oxide synthase(nNOS)was the producer of nitric oxide(NO)which played important gas messenger molecules in biological process.It also can take effect as immune regulation molecule in organism.Black rockfish(Sebastes schlegelii)is an important economic fish which were widely farmed in East Asia countries.Meanwhile,the pathogenic bacteria such as the Edwardsiella tarda and Vibrio anguillarum in seawater always brought serious obstacles to their healthy growth.In order to explore the expression pattern of n NOS gene under the pathogen stimulation and predict its immune function,the n NOS gene in black rockfish named Ssn NOS was identified.It was 3780 bp in length,located on chromosome 6,and contained 27 coding domain sequence(CDs).According to the phylogenetic analysis,the Ssn NOS showed closest relative to the counterpart gene of swamp eel(Monopterus albus).Meanwhile,analysis of Ssn NOS expression in various healthy tissues showed that Ssn NOS expression level was highest in healthy brain tissues,followed by intestinal tissues.In addition,Ssn NOS showed significant expression changes in response to stimulation by two pathogens.Particular in gill,the expression of Ssn NOS after pathogenic stimulation increased significantly.The Elisa analysis showed the Ssn NOS content in gills was much higher than that in other tissues at all time points.Moreover,the expression patterns of Ssn NOS in brain,intestine and kidney after stimulation by pathogens showed a distinct expression pattern which first down-regulated and then up-regulated.Therefore,the Ssn NOS may be an important signaling molecule for fish to respond rapidly in immune stimulation.
基金supported by the National Natural Science Foundation of China(31771876)the Sichuan Province Science and Technology Program(2021YFYZ0011,2021YFYZ0017).
文摘Callose contributes to many biological processes of higher plants including pollen development,cell plate and vascular tissue formation,as well as regulating the transport function of plasmodesmata.The functions of callose synthase genes in maize have been little studied.We describe a maize male-sterile mutant 39(ms39)characterized by reduced plant height.In this study,we confirmed using CRISPR/Cas9 technology that a mutation in Zm00001d043909(ZmCals12),encoding a callose synthase,is responsible for the male sterility of the ms39 mutant.Compared with male-fertile plants,callose deposition around the dyads and tetrads in ms39 anthers was significantly reduced.Increased cell autophagy observed in ms39 anthers may have been due to the premature programmed cell death of tapetal cells,leading to collapse of the anther wall structure.Disordered glucose metabolism in ms39 may have intensified autophagy in anthers.Evaluation of the ms39 gene on maize heterosis by paired-crossed experiment with 11 maize inbred lines indicated that ms39 can be used for maize hybrid seed production.
基金the S and T Program of Hebei,No.22377704DMedical Science Research Project of Hebei Province,No.20190510Postgraduate’s Innovation Fund Project of Hebei Province,No.CXZZBS2021077.
文摘BACKGROUND Oxaliplatin(Oxa)is the first-line chemotherapy drug for colorectal cancer(CRC),and Oxa resistance is crucial for treatment failure.Prostaglandin F_(2α)synthase(PGF 2α)(PGFS),an enzyme that catalyzes the production of PGF_(2α),is involved in the proliferation and growth of a variety of tumors.However,the role of PGFS in Oxa resistance in CRC remains unclear.AIM To explore the role and related mechanisms of PGFS in mediating Oxa resistance in CRC.METHODS The PGFS expression level was examined in 37 pairs of CRC tissues and paracancerous tissues at both the mRNA and protein levels.Overexpression or knockdown of PGFS was performed in CRC cell lines with acquired Oxa resistance(HCT116-OxR and HCT8-OxR)and their parental cell lines(HCT116 and HCT8)to assess its influence on cell proliferation,chemoresistance,apoptosis,and DNA damage.For determination of the underlying mechanisms,CRC cells were examined for platinum-DNA adducts and reactive oxygen species(ROS)levels in the presence of a PGFS inhibitor or its products.RESULTS Both the protein and mRNA levels of PGFS were increased in the 37 examined CRC tissues compared to the adjacent normal tissues.Oxa induced PGFS expression in the parental HCT116 and HCT8 cells in a dosedependent manner.Furthermore,overexpression of PGFS in parental CRC cells significantly attenuated Oxainduced proliferative suppression,apoptosis,and DNA damage.In contrast,knockdown of PGFS in Oxa-resistant HCT116 and HCT8 cells(HCT116-OxR and HCT8-OxR)accentuated the effect of Oxa treatment in vitro and in vivo.The addition of the PGFS inhibitor indomethacin enhanced the cytotoxicity caused by Oxa.Treatment with the PGFS-catalyzed product PGF_(2α)reversed the effect of PGFS knockdown on Oxa sensitivity.Interestingly,PGFS inhibited the formation of platinum-DNA adducts in a PGF_(2α)-independent manner.PGF_(2α)exerts its protective effect against DNA damage by reducing ROS levels.CONCLUSION PGFS promotes resistance to Oxa in CRC via both PGF_(2α)-dependent and PGF_(2α)-independent mechanisms.
基金This research was funded by the National Key Research and Development Program of China,grant number 2016YFD0101418the National Natural Science Foundation of China,grant number 32172047.
文摘Background Herbicide tolerance in crops enables them to survive when lethal doses of herbicides are applied to surrounding weeds.Herbicide-tolerant crops can be developed through transgenic approaches or traditional mutagenesis approaches.At present,no transgenic herbicide tolerant cotton have been commercialized in China due to the genetically-modified organism(GMO)regulation law.We aim to develop a non-transgenic herbicide-tolerant cotton through ethyl methanesulfonate(EMS)mutagenesis,offering an alternative choice for weed management.Results Seeds of an elite cotton cultivar Lumianyan 37(Lu37)were treated with EMS,and a mutant Lu37-1 showed strong tolerance to imidazolinone(IMI)herbicides was identified.A novel nonsynonymous substitution mutation Ser642Asn at acetolactate synthase(ALS)(Gh_D10G1253)in Lu37-1 mutant line was found to be the potential cause to the IMI herbicides tolerance in cotton.The Ser642Asn mutation in ALS did not present among the genomes of natural Gossypium species.Cleaved amplified polymorphic sequence(CAPS)markers were developed to identify the ALS mutant allele.The Arabidopsis overexpressing the mutanted ALS also showed high tolerance to IMI herbicides.Conclusion The nonsynonymous substitution mutation Ser642Asn of the ALS gene Gh_D10G1253 is a novel identi-fied mutation in cotton.This substitution mutation has also been identified in the orthologous ALS genes in other crops.This mutant ALS allele can be used to develop IMI herbicide-tolerant crops via a non-transgenic or transgenic approach.
基金supported by grants from the National Natural Science Foundation of China(No.92049107 and No.31929002)the Innovative Research Groups of the National Natural Science Foundation of China(No.81721005)the Academic Frontier Youth Team Project to Xiaochuan Wang from Huazhong University of Science and Technology.
文摘Alzheimer’s disease (AD) is the most prevalent cause of dementia worldwide. Because of the progressive neurodegeneration, individual cognitive and behavioral functions are impaired, affecting the quality of life of millions of people. Although the exact pathogenesis of AD has not been fully elucidated, amyloid plaques, neurofibrillary tangles (NFTs), and sustaining neuroinflammation dominate its characteristics. As one of the major tau kinases leading to hyperphosphorylation and aggregation of tau, glycogen synthase kinase-3β (GSK-3β) has been drawing great attention in various AD studies. Another research focus of AD in recent years is the inflammasome, a multiprotein complex acting as a regulator in immunological reactions to exogenous and endogenous danger signals, of which the Nod-like receptor (NLR) family, pyrin domain-containing 3 (NLRP3) inflammasome has been studied mostly in AD and proven to play a significant role in AD development by its activation and downstream effects such as caspase-1 maturation and interleukin (IL)-1β release. Studies have shown that the NLRP3 inflammasome is activated in a GSK-3β-dependent way and that inhibition of the NLRP3 inflammasome downregulates GSK-3β, suggesting that these two important proteins are closely related. This article reviews the respective roles of GSK-3β and the NLRP3 inflammasome in AD as well as their relationship and interaction.
基金The study was reviewed and approved by the Institutional Review Board of The First Affiliated Hospital of Gannan Medical College,No.20141219.
文摘BACKGROUND Clinical prognosis often worsens due to high recurrence rates following radical surgery for colon cancer.The examination of high-risk recurrence factors post-surgery provides critical insights for disease evaluation and treatment planning.AIM To explore the relationship between metastasis-associated factor-1 in colon cancer(MACC1)and vacuolar ATP synthase(V-ATPase)expression in colon cancer tissues,and recurrence rate in patients undergoing radical colon cancer surgery.METHODS We selected 104 patients treated with radical colon cancer surgery at our hospital from January 2018 to June 2021.Immunohistochemical staining was utilized to assess the expression levels of MACC1 and V-ATPase in these patients.RESULTS The rates of MACC1 and V-ATPase positivity were 64.42%and 67.31%,respe-ctively,in colon cancer tissues,which were significantly higher than in paracan-cerous tissues(P<0.05).Among patients with TNM stage III,medium to low differentiation,and lymph node metastasis,the positive rates of MACC1 and V-ATPase were significantly elevated in comparison to patients with TNM stage I-II,high differentiation,and no lymph node metastasis(P<0.05).The rate of MACC1 positivity was 76.67%in patients with tumor diameters>5 cm,notably higher than in patients with tumor diameters≤5 cm(P<0.05).We observed a positive correlation between MACC1 and V-ATPase expression(rs=0.797,P<0.05).The positive rates of MACC1 and V-ATPase were significantly higher in patients with recurrence compared to those without(P<0.05).Logistic regression analysis revealed TNM stage,lymph node metastasis,MACC1 expression,and V-ATPase expression as risk factors for postoperative colon cancer recurrence(OR=6.322,3.435,2.683,and 2.421;P<0.05).CONCLUSION The upregulated expression of MACC1 and V-ATPase in colon cancer patients appears to correlate with clinicopathological features and post-radical surgery recurrence.
文摘AIM: To study the distribution of nitric oxide synthase (NOS) in rat stomach myenteric plexus.METHODS: The distribution of NOS in gastric wall was studied in quantity and location by the NADPH-diaphorase (NDP) histochemical staining method and whole mount preparation technique.RESULTS: NOS was distributed in whole stomach wall, most of them were located in myenteric plexus, and distributed in submucosal plexus. The shape of NOS positive neurons was basically similar, most of them being round and oval in shape. But their density, size and staining intensity varied greatly in the different parts of stomach. The density was 62 -± 38 cells/mm2(antrum), 43 ± 32 cells/mm2(body), and 32 ± 28 cells/mm2 (fundus), respectively. The size and staining intensity of NOS positive neurons in the fundus were basically the same, the neurons being large and dark stained, while they were obviously different in antrum. In the body of the stomach, the NOS positive neurons were in an intermediate state from fundus to antrum. There were some beadlike structures which were strung together by NOS positive varicosities in nerve fibers, some were closely adherent to the outer walls of blood vessels.CONCLUSION: Nitric oxide might he involved in the modulation of motility, secretion and blood ciroulation of the stomach, and the significant difference of NOS positive neurons in different parts of stomach myenteric plexus may be related to the physiologic function of stomach.
基金the Applied Science Foundation of Jiangsu Province,China,No.BJ97071
文摘INTRODUCTIONThe treatment of human epithelial malignancies islimited by drug resistance and toxic and side effects,which results in the failure in the treatment ofmajority of advanced cancer victims.To seek for anew,and specific antineoplastic therapy willprovide hope for tumor treatment.Althoughdisordered intermediary metabolism in cancer cellshas been known for many years,much of the
基金supported in part by the National Natural Science Foundation of China (31372038)the Natural Basic Research Plan in Shaanxi Province of China (2015JQ3082)
文摘Sucrose synthases(SUS) are a family of enzymes that play pivotal roles in carbon partitioning, sink strength and plant development. A total of 11 SUS genes have been identified in the genome of Malus domestica(Md SUSs), and phylogenetic analysis revealed that the Md SUS genes were divided into three groups, named as SUS I, SUS II and SUS III, respectively. The SUS I and SUS III groups included four homologs each, whereas the SUS II group contained three homologs. SUS genes in the same group showed similar structural characteristics, such as exon number, size and length distribution. After assessing four different tissues, Md SUS1 s and Md SUS2.1 showed the highest expression in fruit, whereas Md SUS2.2/2.3 and Md SUS3 s exhibit the highest expression in shoot tips. Most Md SUSs showed decreased expression during fruit development, similar to SUS enzyme activity, but both Md SUS2.1 and Md SUS1.4 displayed opposite expression profiles. These results suggest that different Md SUS genes might play distinct roles in the sink-source sugar cycle and sugar utilization in apple sink tissues.
基金funded by the Research Initiative on Development of Transgenic Wheat Plants supported by the Chinese Ministry of Agriculture (2011ZX08002-001)the Natural Science Foundation of China (31171618)the Chinese State Key Laboratory for Biology of Plant Diseases and Insects (SKLOF201307)
文摘Aphids are major agricultural pests that cause significant yield losses in crop plants each year.(E)-β-farnesene(EβF) is the main or only component of an alarm pheromone involved in chemical communication within aphid species and particularly in the avoidance of predation. EβF also occurs in the essential oil of some plant species, and is catalyzed by EβF synthase. By using oligonucleotide primers designed from the known sequence of an EβF synthase gene from black peppermint(Mentha × piperita), two cDNA sequences, MaβFS1 and MaβFS2, were isolated from Asian peppermint(Mentha asiatica). Expression pattern analysis showed that the MaβFS1 gene exhibited higher expression in flowers than in roots, stems and leaves at the transcriptional level. Overexpression of MaβFS1 in tobacco plants resulted in emission of pure EβF ranging from 2.62 to 4.85 ng d-1g-1of fresh tissue. Tritrophic interactions involving peach aphids(Myzus persicae), and predatory lacewing(Chrysopa septempunctata) larvae demonstrated that transgenic tobacco expressing MaβFS1 had lower aphid infestation. This result suggested that the EβF synthase gene from Asian peppermint could be a good candidate for genetic engineering of agriculturally important crop plants.
文摘An efficient and simple method for constructing a genomic DNA library using a TAcloning vector is presented. It is based on the sonicative cleavage of genomic DNA and modification offragment ends with Taq DNA polymerase, followed by ligation using a TA vector. This method was ap-plied for cloning of the phytoene synthase gene crtB from Spirulina platensis. This method is useful whengenomic DNA cannot be efficiently digested with restriction enzymes, a problem often encountered duringthe construction of a genomic DNA library of cyanobacteria.
基金Supported by Ministerio de Ciencia Innovación y Universidades,No.SAF2017-82436R and SAF2016-75004RComunidad de Madrid,No.S2017/BMD-3686+2 种基金Fundación Ramón Areces,No.2016/CIVP18A3864Instituto de Salud Carlos Ⅲby Fondos FEDER,No.Cibercv and Ciberehd
文摘The biosynthesis of prostanoids is involved in both physiological and pathological processes. The expression of prostaglandin-endoperoxide synthase 2(PTGS2; also known as COX-2) has been traditionally associated to the onset of several pathologies, from inflammation to cardiovascular, gastrointestinal and oncologic events. For this reason, the search of selective PTGS2 inhibitors has been a focus for therapeutic interventions. In addition to the classic non-steroidal anti-inflammatory drugs, selective and specific PTGS2 inhibitors, termed coxibs, have been generated and widely used. PTGS2 activity is less restrictive in terms of substrate specificity than the homeostatic counterpart PTGS1, and it accounts for the elevated prostanoid synthesis that accompanies several pathologies. The main regulation of PTGS2 occurs at the transcription level. In addition to this, the stability of the mRNA is finely regulated through the interaction with several cytoplasmic elements, ranging from specificmicroR NAs to proteins that control mR NA degradation. Moreover, the protein has been recognized to be the substrate for several post-translational modifications that affect both the enzyme activity and the targeting for degradation via proteasomal and non-proteasomal mechanisms. Among these modifications, phosphorylation, glycosylation and covalent modifications by reactive lipidic intermediates and by free radicals associated to the proinflammatory condition appear to be the main changes. Identification of these post-translational modifications is relevant to better understand the role of PTGS2 in several pathologies and to establish a correct analysis of the potential function of this protein in diseases progress. Finally, these modifications can be used as biomarkers to establish correlations with other parameters, including the immunomodulation dependent on molecular pathological epidemiology determinants, which may provide a better frame for potential therapeutic interventions.
基金a grant from the KeyBasic Research Program of Shanghai(No.034119922)
文摘BACKGROUND:Nitric oxide(NO)and prostacyclin(PGI2) are both powerful vasoactive substances correlated with the hyperhemodynamics of portal hypertension(PHT), a common syndrome characterized by a pathological increase in portal venous pressure.The purpose of the present study was to evaluate the possible interaction between these two endothelial vasodilators,together with their respective roles in the hyperdynamic splanchnic circulation of PHT. METHODS:Ninety-six male Sprague-Dawley rats were randomly divided into three groups:intrahepatic portal hypertension(IHPH)induced by injection of CCl4(n=31), prehepatic portal hypertension(PHPH)induced by partial stenosis of the portal vein(n=33),and sham-operated controls(SO)(n=32).Animals of each group received indomethacin(INDO),a cyclooxygenase(COX)inhibitor, either short-term(7 days)or long-term(15 days),with saline as control.Free portal pressure(FPP),together with the concentration of NO and PGI2 in serum were measured.The activity of constitutive nitric oxide synthase (cNOS)and inducible nitric oxide synthase(iNOS)in the abdominal aorta and small intestine were determined by spectrophotometry.RT-PCR was performed to measure the levels of cNOS and iNOS mRNA in the arteries and small intestines. RESULTS:Compared with SO rats,the concentrations of NO and PGI2 in PHT rats were elevated,which were consistent with the increased FPP(P<0.05).Although administration of INDO persistently decreased the concentration of PGI2 in serum(P<0.05),the long-term INDO-treated IHPHand PHPH groups had restored splanchnic hyperdynamic circulation,demonstrated by the enhanced FPP(P<0.05). Furthermore,the changes of dynamic circulatory state in both IHPH and PHPH rats were concomitant with the expression and activity of iNOS and the concentration of NO(P<0.05).Although the expression and activity of cNOS in abdominal aorta of PHT rats were higher than in SO rats (P<0.05),there was no difference in small intestinal tissues between PHT and SO rats(P>0.05).Moreover,the changes of iNOS activity and mRNA expression were more marked than cNOS in PHT rats,and there was no difference in expression and activity of cNOS between PHT rats treated by short-and long-term INDO(P>0.05). CONCLUSIONS:iNOS plays an important role in the hemodynamic abnormalities of PHT induced by overproduction of NO.There is a possible interaction between PGI2 and NO in hyperhemodynamics of PHT, but PGI2 may not be a mediator in the formation and development of the hyperdynamic circulatory state in PHT rats.
