Using atom force microscopy (AFM), in vitro transcription, PAGE and other experimental technologies, it is observed that, in active genes of mice (Balb/c) nuclear DNA fragments of non-transcriptional state, only regul...Using atom force microscopy (AFM), in vitro transcription, PAGE and other experimental technologies, it is observed that, in active genes of mice (Balb/c) nuclear DNA fragments of non-transcriptional state, only regulation sequences at both ends are associated with scaffold proteins (indissociable proteins) and some transcriptional factors such as complexes (dissociable proteins) made of gene-coding proteins and specific auxiliary small molecules, while there are no combining proteins in intermediate coding sequences. However, in active genes of transcriptional state, both regulation sequences and intermediate coding sequences are associated with active transcriptional factors by non-covalent bonds.This paper shows the prospective application of AFM observation and in vitro transcription in the research on gene expression and regulation. It also offers some theoretical basis for localization of specific genes in human genomes.展开更多
Liquid-liquid phase separation,a novel biochemical phenomenon,has been increasingly studied for its medical applications.It underlies the formation of membrane-less organelles and is involved in many cellular and biol...Liquid-liquid phase separation,a novel biochemical phenomenon,has been increasingly studied for its medical applications.It underlies the formation of membrane-less organelles and is involved in many cellular and biological processes.During transcriptional regulation,dynamic condensates are formed through interactions between transcriptional elements,such as transcription factors,coactivators,and mediators.Cancer is a disease characterized by uncontrolled cell proliferation,but the precise mechanisms underlying tumorigenesis often remain to be elucidated.Emerging evidence has linked abnormal transcriptional condensates to several diseases,especially cancer,implying that phase separation plays an important role in tumorigenesis.Condensates formed by phase separation may have an effect on gene transcription in tumors.In the present review,we focus on the correlation between phase separation and transcriptional regulation,as well as how this phenomenon contributes to cancer development.展开更多
Glutamatergic projection neurons generate sophisticated excitatory circuits to integrate and transmit information among different cortical areas,and between the neocortex and other regions of the brain and spinal cord...Glutamatergic projection neurons generate sophisticated excitatory circuits to integrate and transmit information among different cortical areas,and between the neocortex and other regions of the brain and spinal cord.Appropriate development of cortical projection neurons is regulated by certain essential events such as neural fate determination,proliferation,specification,differentiation,migration,survival,axonogenesis,and synaptogenesis.These processes are precisely regulated in a tempo-spatial manner by intrinsic factors,extrinsic signals,and neural activities.The generation of correct subtypes and precise connections of projection neurons is imperative not only to support the basic cortical functions(such as sensory information integration,motor coordination,and cognition)but also to prevent the onset and progression of neurodevelopmental disorders(such as intellectual disability,autism spectrum disorders,anxiety,and depression).This review mainly focuses on the recent progress of transcriptional regulations on the development and diversity of neocortical projection neurons and the clinical relevance of the failure of transcriptional modulations.展开更多
Self-rooted apple stock is widely used for apple production.However,the shallowness of the adventitious roots in self-rooted apple stock leads to poor performance in the barren orchards of China.This is because of the...Self-rooted apple stock is widely used for apple production.However,the shallowness of the adventitious roots in self-rooted apple stock leads to poor performance in the barren orchards of China.This is because of the considerable difference in the development of a gravitropic set-point angle(GSA)between self-rooted apple stock and seedling rootstock.Therefore,it is crucial to study the molecular mechanism of adventitious root GSA in self-rooted apple stock for breeding self-rooted and deep-rooted apple rootstock cultivars.An apple auxin response factor MdARF19 functioned to establish the adventitious root GSA of self-rooted apple stock in response to gravity and auxin signals.MdARF19 bound directly to the MdPIN7 promoter,activating its transcriptional expression and thus regulating the formation of the adventitious root GSA in 12-2 self-rooted apple stock.However,MdARF19 influenced the expression of auxin efflux carriers(MdPIN3 and MdPIN10)and the establishment of adventitious root GSA of self-rooted apple stock in response to gravity signals by direct activation of MdFLP.Our findings provide new information on the transcriptional regulation of MdPIN7 by auxin response factor MdARF19 in the regulation of the adventitious root GSA of self-rooted apple stock in response to gravity and auxin signals.展开更多
Drought stress impairs crop growth and development.BEL1-like family transcription factors may be involved in plant response to drought stress,but little is known of the molecular mechanism by which these proteins regu...Drought stress impairs crop growth and development.BEL1-like family transcription factors may be involved in plant response to drought stress,but little is known of the molecular mechanism by which these proteins regulate plant response and defense to drought stress.Here we show that the BEL1-like transcription factor GhBLH5-A05 functions in cotton(Gossypium hirsutum)response and defense to drought stress.Expression of GhBLH5-A05 in cotton was induced by drought stress.Overexpression of GhBLH5-A05 in both Arabidopsis and cotton increased drought tolerance,whereas silencing GhBLH5-A05 in cotton resulted in elevated sensitivity to drought stress.GhBLH5-A05 binds to cis elements in the promoters of GhRD20-A09 and GhDREB2C-D05 to activate the expression of these genes.GhBLH5-A05 interacted with the KNOX transcription factor GhKNAT6-A03.Co-expression of GhBLH5-A05 and GhKNAT6-A03 increased the transcription of GhRD20-A09 and GhDREB2C-D05.We conclude that GhBLH5-A05 acts as a regulatory factor with GhKNAT6-A03 functioning in cotton response to drought stress by activating the expression of the drought-responsive genes GhRD20-A09 and GhDREB2C-D05.展开更多
Northern blot analysis was conducted with mitochondrial RNA from seedling leaves, floral buds, and developing seeds of NCa CMS, maintainer line and fertile F1 using ten mitochondrial genes as probes. The results revea...Northern blot analysis was conducted with mitochondrial RNA from seedling leaves, floral buds, and developing seeds of NCa CMS, maintainer line and fertile F1 using ten mitochondrial genes as probes. The results revealed that 9 out of the 10 mitochondrial genes, except for atp6, showed no difference in different tissues of the corresponding materials of NCα CMS system and that they might be constitutively expressed genes. Eight genes, such as orf139, orf222, atpl, cox1, cox2, cob, rm5S, and rm26S, showed no difference among the three tissues of all the materials detected. So the expression of these eight genes was not regulated by nuclear genes and was not tissue-specific. The transcripts of atp9 were identical among different tissues, but diverse among different materials, indicating that transcription of atp9 was neither controlled by nuclear gene nor tissue-specific. Gene atp6 displayed similar transcripts with the same size among different tissues of all the materials but differed in abundance among tissues of corresponding materials and its expression might be tissue-specific under regulation of nuclear gene. Moreover, three transcripts of orf222 were detected in the floral buds of NCa cms and fertile F1, but no transcript was detected in floral buds of the maintainer line.The transcription of orf139 was similar to that of orf222 but only two transcripts of 0.8 kb and 0.6 kb were produced. The atp9 probe detected a single transcript of 0.6 kb in NCa cms and in maintainer line and an additional transcript of 1.2 kb in fertile F1. The relationship of expression of orf222, orf139, and atp9 with NCa sterility was discussed.展开更多
Maize(Zea mays L.)is one of the most important food crops in the world,and starch is the main component of its endosperm.Transcriptional regulation plays a vital role in starch biosynthesis.However,it is not well unde...Maize(Zea mays L.)is one of the most important food crops in the world,and starch is the main component of its endosperm.Transcriptional regulation plays a vital role in starch biosynthesis.However,it is not well understood in maize.We report the identification of the transcription factor ZmNAC126 and its role in regulation of starch synthesis in maize.Transcriptional expression of ZmNAC126 was higher in maize endosperm and kernels than in roots or stems.ZmNAC126 shared a similar expression pattern with starch synthesis genes during seed development,and its expression pattern was also consistent with the accumulation of starch.ZmNAC126 is a typical transcription factor with a transactivation domain between positions 201 and 227 of the amino acid sequence,is located in the nucleus,and binds to CACG repeats in vitro.Yeast one-hybrid assay revealed that ZmNAC126 bound the promoters of ZmGBSSI,ZmSSIIa,ZmSSIV,ZmISA1,and ZmISA2.Transient overexpression of ZmNAC126 in maize endosperm increased the activities of promoters pZmSh2,pZmBt2,pZmGBSSI,pZmSSIIIa,and pZmBT1 but inhibited the activities of pZmISA1 and pZmISA2.ZmNAC126 thus acts in starch synthesis by transcriptionally regulating targeted starch synthesis-related genes in maize kernels.展开更多
The Mediator complex is an important component of the eukaryotic transcriptional machinery. As an essential link between transcription factors and RNA polymerase II, the Mediator complex transduces diverse signals to ...The Mediator complex is an important component of the eukaryotic transcriptional machinery. As an essential link between transcription factors and RNA polymerase II, the Mediator complex transduces diverse signals to genes involved in different pathways. The plant Mediator complex was recently purified and comprises conserved and specific subunits. It functions in concert with transcription factors to modulate various responses. In this review, we summarize the recent advances in understanding the plant Mediator complex and its diverse roles in plant growth, development, defense, non-coding RNA production, response to abiotic stresses, flowering, genomic stability and metabolic homeostasis. In addition, the transcription factors interacting with the Mediator complex are also highlighted.展开更多
Rewiring and reprogramming of transcriptional regulation took place during bacterial speciation. The mechanistic alterations among tran- scription factors, cis-regulatory elements and target genes confer bacteria nove...Rewiring and reprogramming of transcriptional regulation took place during bacterial speciation. The mechanistic alterations among tran- scription factors, cis-regulatory elements and target genes confer bacteria novel ability to adapt to stochastic environmental changes. This process is critical to their survival, especially for bacterial pathogens subjected to accelerated evolution. In the past two decades, the investigators not only completed the sequences of numerous bacterial genomes, but also made great progress in understanding the molecular basis of evolution. Here we briefly reviewed the current knowledge on the mechanistic changes among orthologous, paralogous and xenogenic regulatory circuits, which were caused by genetic recombinations such as gene duplication, horizontal gene transfer, transposable elements and different genetic contexts. We also discussed the potential impact of this area on theoretical and applied studies of microbes.展开更多
The protein HTRP (human transcription regulator protein) is encoded by the differential gene htrp and induced by Herpes simplex virus type 1 (HSV-1) infection in KMB-17 cells.HTRP was found to interact with SAP30 (mSi...The protein HTRP (human transcription regulator protein) is encoded by the differential gene htrp and induced by Herpes simplex virus type 1 (HSV-1) infection in KMB-17 cells.HTRP was found to interact with SAP30 (mSin3A Association Protein),one of the components of co-repressor complex mSin3A,which is part of the deacetylation transfer enzyme HDAC.To reveal the biological significance of the interaction between HTRP and SAP30,real-time PCR and a dual-luciferase detecting system was used.The results indicate that HTRP could inhibit the transcription of a viral promoter,whose interaction with SAP30 synergistically affects transcriptional inhibition of the viral genes,and is related to HDAC enzyme activity.ChIP experiments demonstrate that HTRP could promote HDAC activity by increasing the deacetylation level of lysine 14 and lysine 9 in histone H3.展开更多
Atherosclerosis is a progressive human pathology that encompasses several stages of development. Endothelial dysfunction represents an early sign of lesion within the vasculature. A number of risk factors for atherosc...Atherosclerosis is a progressive human pathology that encompasses several stages of development. Endothelial dysfunction represents an early sign of lesion within the vasculature. A number of risk factors for atherosclero- sis, including hyperlipidemia, diabetes, and hypertension, target the vascular endothelium by re-programming its transcriptome. These profound alterations taking place on the chromatin rely on the interplay between sequence specific transcription factors and the epigenetic machinery. The epigenetic machinery, in turn, tailor individual transcription events key to atherogenesis to intrinsic and extrinsic insults dictating the development of atheroscle- rotic lesions. This review summarizes our current understanding of the involvement of the epigenetic machinery in endothelial injury during atherogenesis.展开更多
Background: We aim to address one question: do cancer vs. normal tissue cells execute their transcription regulation essentially the same or differently, and why? Methods: We utilized an integrated computational s...Background: We aim to address one question: do cancer vs. normal tissue cells execute their transcription regulation essentially the same or differently, and why? Methods: We utilized an integrated computational study of cancer epigenomes and transcriptomes of 10 cancer types, by using penalized linear regression models to evaluate the regulatory effects of DNA methylations on gene expressions. Results: Our main discoveries are: (i) 56 genes have their expressions consistently regulated by DNA methylation specifically in cancer, which enrich pathways associated with micro-environmental stresses and responses, particularly oxidative stress; (ii) the level of involvement by DNA methylation in transcription regulation increases as a cancer advances for majority of the cancer types examined; (iii) transcription regulation in cancer vs. control tissue cells are substantially different, with the former being largely done through direct DNA methylation and the latter mainly done via transcriptional factors; (iv) the altered DNA methylation landscapes in cancer vs. control are predominantly accomplished by DNMTI, TET3 and CBX2, which are predicted to be the result of persistent stresses present in the intracellular and micro-environments of cancer cells, which is consistent with the general understanding about epigenomic functions. Conclusions: Our integrative analyses discovered that a large class of genes is regulated via direct DNA methylation of the genes in cancer, comparing to TFs in normal cells. Such genes fall into a few stress and response pathways. As a cancer advances, the level of involvement by direct DNA methylation in transcription regulation increases for majority of the cancer types examined.展开更多
SrUGT76G1,the most well-studied diterpene glycosyltransferase in Stevia rebaudiana,is key to the biosynthesis of economically important steviol glycosides(SGs).However,the molecular regulatory mechanism of SrUGT76G1 h...SrUGT76G1,the most well-studied diterpene glycosyltransferase in Stevia rebaudiana,is key to the biosynthesis of economically important steviol glycosides(SGs).However,the molecular regulatory mechanism of SrUGT76G1 has rarely been explored.In this study,we identified a MYB transcription factor,SrMYB1,using a yeast one-hybrid screening assay.SrMYB1 belongs to the typical R2R3-type MYB protein and is specifically localized in the nucleus with strong transactivation activity.The transcript of SrMYB1 is predominantly accumulated in flowers,but is also present at a lower level in leaves.Yeast one-hybrid and electrophoretic mobility shift assays verified that SrMYB1 binds directly to the MYB binding sites in the F4-3 fragment(+50–(–141))of the SrUGT76G1 promoter.Furthermore,we found that SrMYB1 could significantly repress the expression of SrUGT76G1 in both epidermal cells of tobacco leaves and stevia callus.Taken together,our results demonstrate that SrMYB1 is an essential upstream regulator of SrUGT76G1 and provide novel insight into the regulatory network for the SGs metabolic pathway in S.rebaudiana.展开更多
The factor in the germline alpha(figla), as a member of the basic helix-loop-helix family, has been reported to be involved in ovary development in mammals and teleosts. However, the regulatory mechanisms of figla in ...The factor in the germline alpha(figla), as a member of the basic helix-loop-helix family, has been reported to be involved in ovary development in mammals and teleosts. However, the regulatory mechanisms of figla in teleosts remain unclear. Here,figla in P. olivaceus(Pofigla) was characterized with encoding a 202 amino acid protein that contains a conserved basic region and helix-loop-helix(HLH) domain. Amino acids alignment and synteny analysis revealed that Pofigla was conserved with the orthologous gene sequences in other vertebrates. The results of qRT-PCR showed Pofigla was maternally inherited during embryonic development. For tissue distribution, Pofigla showed a sexually dimorphic gene expression in the gonad of different genders, with a higher expression in ovary than in testis. In situ hybridization(ISH) results demonstrated Pofigla was specifically expressed in germ cells including oocytes, spermatogonia and spermatocytes. By screening and analyzing two proximal regions(-2966/-2126 and-772/-444) with high promoter activity, we found SOX5, LEF1, FOXP1 and GATA1 may play important roles in the transcriptional regulation of Pofigla. Furthermore, we observed the co-localization between Figla and LEF1 in HEK 293T cells. And the significant up-regulation effect of the canonical Wnt signaling pathway on the expression of Pofigla was found in cultured ovarian cells. This study provided the first evidence that figla not only has an important function in ovary development, but also plays some potential roles in testis development and/or male germ cell differentiation during early testis development in P. olivaceus. The results provide valuable reference in exploring the regulatory network of figla in teleost.展开更多
The molecular modifications of Herpes Simplex Virus Type I (HSV-1) proteins represented by acetylation and phosphorylation are essential to its biological functions. The cellular chromatin-remodeling/ assembly is in...The molecular modifications of Herpes Simplex Virus Type I (HSV-1) proteins represented by acetylation and phosphorylation are essential to its biological functions. The cellular chromatin-remodeling/ assembly is involved in HSV-1 associated gene transcriptional regulation in human cells harboring HSV-1 lytic or latent infections. Further investigation on these biological events would provide a better understanding of the mechanisms of HSV-1 viral gene transcriptional regulation展开更多
Human X-box binding protein 1 (XBP1), an important transcription factor, participates in many signal transduction processes. To further investigate the biological function of XBP1, sequences of XBP1 promoter and its...Human X-box binding protein 1 (XBP1), an important transcription factor, participates in many signal transduction processes. To further investigate the biological function of XBP1, sequences of XBP1 promoter and its two deletion mutants were first determined using bioinformatic analysis. The report vectors containing XBP1 promoter and its deletion mutants were then constructed, namely, p1-XBPlp, p2-XBPlp, and p3-XBPlp. Each reporter vector was separately transfected into HepG2, L02, K562, SMMC-7721, HSF, and Lipocyte lto Cell line using FuGENE 6 transfection reagents. The activity of chloramphenicol acetyltransferase (CAT) in each group of transfected cells was detected by ELISA assay, which in turn reflects the transcription activity of the XBP1 gene promoter. The activity involving p3-XBPlp was the highest in HepG2, which was 12.4-fold of that of pCAT3-Basic. The activities of p3-XBPlp in K562 and SMMC-7721 were the second and the third highest, which were 10.9-fold and 10.0-fold of that of the pCAT3-Basic, respectively. The CAT activity in L02 was lower than that in the above-mentioned abnormal cell, and no reporter activity was detected in HSF and Ito Cell. The XBP1 transcription and expression in K562, HepG2 and SMMC-7721 were found to be higher than that in L02, HSF and Ito cells, based on the results of real-time RT-PCR and Western blot. The XBP1 transcription and expression in L02, HSF was lower, whereas that in Ito cells was totally lacking. The result was similar to that of CAT-ELISA. Therefore, the XBP1 gene promoter can drive its downstream gene expression and its activity is cell line-dependent. The core sequence of XBP1 promoter was found between -227bp and 66bp sequence. This sequence was closely associated with the transcriptional activity of XBP1 promoter.展开更多
The hepatocellular carcinoma suppressor 1 (HCCS1) gene was identified by both positional cloning from a predominant region of loss of heterozygosity (17p 13.3) in liver cancer and by functional screening for genes...The hepatocellular carcinoma suppressor 1 (HCCS1) gene was identified by both positional cloning from a predominant region of loss of heterozygosity (17p 13.3) in liver cancer and by functional screening for genes affecting cell proliferation in large-scale transfection assays. Its overexpression results in inhibition of cell proliferation in cell culture and tumor growth in nude mice. To understand its transcription regulation, the promoter architecture has been dissected in detail. The major start of transcription was mapped by primer extension to a C residue, 177 nucleotides upstream of the ATG codon. By assessing the promoter activity of a set of linker-scanning mutants of the minimal promoter (-60 to +148 region) in a transient transfection assay, we found that the +1 to + 40 region is critical to HCCS1 gene transcription, containing binding sites for transcription factors NF-kB (-21 to +7 and +40 to +26), p53 (+29 to +9) and ETS (+4 to +20 and +23 to +39). Biochemical and molecular analyses revealed that the ETS transcription factors ETS-2 and Elf-1 bind to the two ETS sites in situ and contribute significantly to the transcriptionally active state of the HCCS1 gene, while NF-kB, p53 and two other members of the ETS family (ETS-1 and NERF2) appear to play little role. Our observations provide insight into the mechanistic aspects of HCCS1 transcription regulation.展开更多
To clone and identify the proteins involved in regulating the transcription of hTERT and study the role of genes in both hTERT transcription and telomerase activity. Methods The full cDNA of COUP-TFII was clon...To clone and identify the proteins involved in regulating the transcription of hTERT and study the role of genes in both hTERT transcription and telomerase activity. Methods The full cDNA of COUP-TFII was cloned from HeLa cDNA library by hTERT promoter-based yeast one-hybrid assay and then in-frame inserted into His-tag fusion expression vector pEK318. The His-tag COUP-TFII fusion proteins were purified by Ni-NTA chromatography. The interaction of COUP-TFII with hTERT promoter in vitro was identified by electrophoretic mobility shift assay and Footprint. The role of COUP-TFII in both hTERT transcription and telomerase activity were probed through Luciferase reporter assay, Northern blot, and TRAP-PCR ELISA. Results COUP-TFII could firmly bind to the downstream E-box and the other two binding sites in hTERT promoter. Luciferase reporter assay indicated COUP-TFII could suppress hTERT promoter activity and stable introduction of COUP-TFII into HeLa cells also decreased both endogenous hTERT transcription and telomerase activity. Conclusion The human COUP-TFII can firmly bind to hTERT promoter, and inhibit telomerase activity through decreasing hTERT transcription. It will greatly facilitate understanding of telomerase regulation in normal and cancer cells展开更多
The human RNA methyltransferase like 1 gene (RNMTL1) is one of thirteen newly discovered genes within a 116 Kb segment of the chromosome 17pl3.3 that suffers from a high frequent loss of heterozygosity in human hepato...The human RNA methyltransferase like 1 gene (RNMTL1) is one of thirteen newly discovered genes within a 116 Kb segment of the chromosome 17pl3.3 that suffers from a high frequent loss of heterozygosity in human hepatocellular carcinoma in China[1-5]. To understand the molecular mechanisms underlying transcription control of the RNMTL1 gene in human cancers, we decline using of the conventional approach where the cis-elements bound by the known transcription factors are primary targets, and carried out the systematic analyses to dissect the promoter structure and identify/characterize the key cis-elements that are responsible for its strong expression in cell. The molecular approaches applied included 1, the primer extension for mapping of the transcription starts; 2, the transient transfection/reporter assays on a large number of deletion and site-specific mutants of the promoter segment for defining the minimal promoter and the crucial elements within; and 3, the electrophoresis mobility shift assay with specific antibodies for reconfirming the nature of the transcription factors and their cognate cis-elements. We have shown that the interaction of an ATF/CREB element (-38 to -31) and its cognate transcription factors play a predominant role in the promoter activity of the RNMTL1 gene. The secondary DNA structures of the ATF/CREB element play a more vital role in the protein-DNA interaction. Finally, we reported a novel mechanism underlying the YY1 mediated transcription repression, namely, the ATF/CREB dependent transcription-repression by YY1 is executed in absence of its own sequence-specific binding.展开更多
Kruppel-like factor 4(Klf4) is a zinc finger transcription factor and plays crucial roles in Xenopus embryogenesis.However, its regulation during embryogenesis is still unclear. Here, we report that Tcf711, a key do...Kruppel-like factor 4(Klf4) is a zinc finger transcription factor and plays crucial roles in Xenopus embryogenesis.However, its regulation during embryogenesis is still unclear. Here, we report that Tcf711, a key downstream transducer of the Wnt signaling pathway, could promote Klf4 transcription and stimulate Klf4 promoter activity in early Xenopus embryos. Furthermore, cycloheximide treatment showed a direct effect on Klf4 transcription facilitated by Tcf711. Moreover, the dominant negative form of Tcf711(dnTcf711), which lacks N-terminus of the β-catenin binding motif, could still activate Klf4 transcription, suggesting that this regulation is Wnt/β-catenin independent.Taken together, our results demonstrate that Tcf711 lies upstream of Klf4 to maintain its expression level during Xenopus embryogenesis.展开更多
文摘Using atom force microscopy (AFM), in vitro transcription, PAGE and other experimental technologies, it is observed that, in active genes of mice (Balb/c) nuclear DNA fragments of non-transcriptional state, only regulation sequences at both ends are associated with scaffold proteins (indissociable proteins) and some transcriptional factors such as complexes (dissociable proteins) made of gene-coding proteins and specific auxiliary small molecules, while there are no combining proteins in intermediate coding sequences. However, in active genes of transcriptional state, both regulation sequences and intermediate coding sequences are associated with active transcriptional factors by non-covalent bonds.This paper shows the prospective application of AFM observation and in vitro transcription in the research on gene expression and regulation. It also offers some theoretical basis for localization of specific genes in human genomes.
基金supported by the Jiangsu Province Natural Science Foundation(Grant No.BK20201492)the Key Medical Research Project of Jiangsu Provincial Health Commission(Grant No.K2019002)the Clinical Capacity Improvement Project of Jiangsu Province People's Hospital(Grant No.JSPH-MA-2021-8).
文摘Liquid-liquid phase separation,a novel biochemical phenomenon,has been increasingly studied for its medical applications.It underlies the formation of membrane-less organelles and is involved in many cellular and biological processes.During transcriptional regulation,dynamic condensates are formed through interactions between transcriptional elements,such as transcription factors,coactivators,and mediators.Cancer is a disease characterized by uncontrolled cell proliferation,but the precise mechanisms underlying tumorigenesis often remain to be elucidated.Emerging evidence has linked abnormal transcriptional condensates to several diseases,especially cancer,implying that phase separation plays an important role in tumorigenesis.Condensates formed by phase separation may have an effect on gene transcription in tumors.In the present review,we focus on the correlation between phase separation and transcriptional regulation,as well as how this phenomenon contributes to cancer development.
基金supported by Guangdong Provincial Basic and Applied Basic Research Fund,No.2021A1515011299(to KT)。
文摘Glutamatergic projection neurons generate sophisticated excitatory circuits to integrate and transmit information among different cortical areas,and between the neocortex and other regions of the brain and spinal cord.Appropriate development of cortical projection neurons is regulated by certain essential events such as neural fate determination,proliferation,specification,differentiation,migration,survival,axonogenesis,and synaptogenesis.These processes are precisely regulated in a tempo-spatial manner by intrinsic factors,extrinsic signals,and neural activities.The generation of correct subtypes and precise connections of projection neurons is imperative not only to support the basic cortical functions(such as sensory information integration,motor coordination,and cognition)but also to prevent the onset and progression of neurodevelopmental disorders(such as intellectual disability,autism spectrum disorders,anxiety,and depression).This review mainly focuses on the recent progress of transcriptional regulations on the development and diversity of neocortical projection neurons and the clinical relevance of the failure of transcriptional modulations.
基金the National Natural Science Foundation of China(Grant Nos.32102310,32202484,and 32072520)the Shandong Key Research and Development Program,China(Grant Nos.2021LZGC007 and 2022TZXD009).
文摘Self-rooted apple stock is widely used for apple production.However,the shallowness of the adventitious roots in self-rooted apple stock leads to poor performance in the barren orchards of China.This is because of the considerable difference in the development of a gravitropic set-point angle(GSA)between self-rooted apple stock and seedling rootstock.Therefore,it is crucial to study the molecular mechanism of adventitious root GSA in self-rooted apple stock for breeding self-rooted and deep-rooted apple rootstock cultivars.An apple auxin response factor MdARF19 functioned to establish the adventitious root GSA of self-rooted apple stock in response to gravity and auxin signals.MdARF19 bound directly to the MdPIN7 promoter,activating its transcriptional expression and thus regulating the formation of the adventitious root GSA in 12-2 self-rooted apple stock.However,MdARF19 influenced the expression of auxin efflux carriers(MdPIN3 and MdPIN10)and the establishment of adventitious root GSA of self-rooted apple stock in response to gravity signals by direct activation of MdFLP.Our findings provide new information on the transcriptional regulation of MdPIN7 by auxin response factor MdARF19 in the regulation of the adventitious root GSA of self-rooted apple stock in response to gravity and auxin signals.
基金supported by the Project from the Ministry of Agriculture of China for Transgenic Research(2014ZX0800927B)the National Natural Science Foundation of China(31871667).
文摘Drought stress impairs crop growth and development.BEL1-like family transcription factors may be involved in plant response to drought stress,but little is known of the molecular mechanism by which these proteins regulate plant response and defense to drought stress.Here we show that the BEL1-like transcription factor GhBLH5-A05 functions in cotton(Gossypium hirsutum)response and defense to drought stress.Expression of GhBLH5-A05 in cotton was induced by drought stress.Overexpression of GhBLH5-A05 in both Arabidopsis and cotton increased drought tolerance,whereas silencing GhBLH5-A05 in cotton resulted in elevated sensitivity to drought stress.GhBLH5-A05 binds to cis elements in the promoters of GhRD20-A09 and GhDREB2C-D05 to activate the expression of these genes.GhBLH5-A05 interacted with the KNOX transcription factor GhKNAT6-A03.Co-expression of GhBLH5-A05 and GhKNAT6-A03 increased the transcription of GhRD20-A09 and GhDREB2C-D05.We conclude that GhBLH5-A05 acts as a regulatory factor with GhKNAT6-A03 functioning in cotton response to drought stress by activating the expression of the drought-responsive genes GhRD20-A09 and GhDREB2C-D05.
基金This work was supported by the National High Technology R&D Project of China (No.2002AA207009) and Wuhan Dawn Project for Youth (No. 20035002016-36).
文摘Northern blot analysis was conducted with mitochondrial RNA from seedling leaves, floral buds, and developing seeds of NCa CMS, maintainer line and fertile F1 using ten mitochondrial genes as probes. The results revealed that 9 out of the 10 mitochondrial genes, except for atp6, showed no difference in different tissues of the corresponding materials of NCα CMS system and that they might be constitutively expressed genes. Eight genes, such as orf139, orf222, atpl, cox1, cox2, cob, rm5S, and rm26S, showed no difference among the three tissues of all the materials detected. So the expression of these eight genes was not regulated by nuclear genes and was not tissue-specific. The transcripts of atp9 were identical among different tissues, but diverse among different materials, indicating that transcription of atp9 was neither controlled by nuclear gene nor tissue-specific. Gene atp6 displayed similar transcripts with the same size among different tissues of all the materials but differed in abundance among tissues of corresponding materials and its expression might be tissue-specific under regulation of nuclear gene. Moreover, three transcripts of orf222 were detected in the floral buds of NCa cms and fertile F1, but no transcript was detected in floral buds of the maintainer line.The transcription of orf139 was similar to that of orf222 but only two transcripts of 0.8 kb and 0.6 kb were produced. The atp9 probe detected a single transcript of 0.6 kb in NCa cms and in maintainer line and an additional transcript of 1.2 kb in fertile F1. The relationship of expression of orf222, orf139, and atp9 with NCa sterility was discussed.
基金supported by the National Natural Science Foundation of China(31571757)the National Key Basic Research Program of China(2014CB138202)。
文摘Maize(Zea mays L.)is one of the most important food crops in the world,and starch is the main component of its endosperm.Transcriptional regulation plays a vital role in starch biosynthesis.However,it is not well understood in maize.We report the identification of the transcription factor ZmNAC126 and its role in regulation of starch synthesis in maize.Transcriptional expression of ZmNAC126 was higher in maize endosperm and kernels than in roots or stems.ZmNAC126 shared a similar expression pattern with starch synthesis genes during seed development,and its expression pattern was also consistent with the accumulation of starch.ZmNAC126 is a typical transcription factor with a transactivation domain between positions 201 and 227 of the amino acid sequence,is located in the nucleus,and binds to CACG repeats in vitro.Yeast one-hybrid assay revealed that ZmNAC126 bound the promoters of ZmGBSSI,ZmSSIIa,ZmSSIV,ZmISA1,and ZmISA2.Transient overexpression of ZmNAC126 in maize endosperm increased the activities of promoters pZmSh2,pZmBt2,pZmGBSSI,pZmSSIIIa,and pZmBT1 but inhibited the activities of pZmISA1 and pZmISA2.ZmNAC126 thus acts in starch synthesis by transcriptionally regulating targeted starch synthesis-related genes in maize kernels.
文摘The Mediator complex is an important component of the eukaryotic transcriptional machinery. As an essential link between transcription factors and RNA polymerase II, the Mediator complex transduces diverse signals to genes involved in different pathways. The plant Mediator complex was recently purified and comprises conserved and specific subunits. It functions in concert with transcription factors to modulate various responses. In this review, we summarize the recent advances in understanding the plant Mediator complex and its diverse roles in plant growth, development, defense, non-coding RNA production, response to abiotic stresses, flowering, genomic stability and metabolic homeostasis. In addition, the transcription factors interacting with the Mediator complex are also highlighted.
基金supported by the National Basic Research Program(No.2011CB 100700)of the Ministry of Science and Technology of Chinathe National Natural Science Foundation of China(Nos.30771401 and 31070081)the Startup Fund from the Institute of Microbiology,Chinese Academy of Sciences
文摘Rewiring and reprogramming of transcriptional regulation took place during bacterial speciation. The mechanistic alterations among tran- scription factors, cis-regulatory elements and target genes confer bacteria novel ability to adapt to stochastic environmental changes. This process is critical to their survival, especially for bacterial pathogens subjected to accelerated evolution. In the past two decades, the investigators not only completed the sequences of numerous bacterial genomes, but also made great progress in understanding the molecular basis of evolution. Here we briefly reviewed the current knowledge on the mechanistic changes among orthologous, paralogous and xenogenic regulatory circuits, which were caused by genetic recombinations such as gene duplication, horizontal gene transfer, transposable elements and different genetic contexts. We also discussed the potential impact of this area on theoretical and applied studies of microbes.
基金The National Natural Science Foundation of China (30670094)the Ph.D. Programs Foundation of Ministry of Education of China (20060023008)
文摘The protein HTRP (human transcription regulator protein) is encoded by the differential gene htrp and induced by Herpes simplex virus type 1 (HSV-1) infection in KMB-17 cells.HTRP was found to interact with SAP30 (mSin3A Association Protein),one of the components of co-repressor complex mSin3A,which is part of the deacetylation transfer enzyme HDAC.To reveal the biological significance of the interaction between HTRP and SAP30,real-time PCR and a dual-luciferase detecting system was used.The results indicate that HTRP could inhibit the transcription of a viral promoter,whose interaction with SAP30 synergistically affects transcriptional inhibition of the viral genes,and is related to HDAC enzyme activity.ChIP experiments demonstrate that HTRP could promote HDAC activity by increasing the deacetylation level of lysine 14 and lysine 9 in histone H3.
文摘Atherosclerosis is a progressive human pathology that encompasses several stages of development. Endothelial dysfunction represents an early sign of lesion within the vasculature. A number of risk factors for atherosclero- sis, including hyperlipidemia, diabetes, and hypertension, target the vascular endothelium by re-programming its transcriptome. These profound alterations taking place on the chromatin rely on the interplay between sequence specific transcription factors and the epigenetic machinery. The epigenetic machinery, in turn, tailor individual transcription events key to atherogenesis to intrinsic and extrinsic insults dictating the development of atheroscle- rotic lesions. This review summarizes our current understanding of the involvement of the epigenetic machinery in endothelial injury during atherogenesis.
文摘Background: We aim to address one question: do cancer vs. normal tissue cells execute their transcription regulation essentially the same or differently, and why? Methods: We utilized an integrated computational study of cancer epigenomes and transcriptomes of 10 cancer types, by using penalized linear regression models to evaluate the regulatory effects of DNA methylations on gene expressions. Results: Our main discoveries are: (i) 56 genes have their expressions consistently regulated by DNA methylation specifically in cancer, which enrich pathways associated with micro-environmental stresses and responses, particularly oxidative stress; (ii) the level of involvement by DNA methylation in transcription regulation increases as a cancer advances for majority of the cancer types examined; (iii) transcription regulation in cancer vs. control tissue cells are substantially different, with the former being largely done through direct DNA methylation and the latter mainly done via transcriptional factors; (iv) the altered DNA methylation landscapes in cancer vs. control are predominantly accomplished by DNMTI, TET3 and CBX2, which are predicted to be the result of persistent stresses present in the intracellular and micro-environments of cancer cells, which is consistent with the general understanding about epigenomic functions. Conclusions: Our integrative analyses discovered that a large class of genes is regulated via direct DNA methylation of the genes in cancer, comparing to TFs in normal cells. Such genes fall into a few stress and response pathways. As a cancer advances, the level of involvement by direct DNA methylation in transcription regulation increases for majority of the cancer types examined.
基金supported by the National Natural Science Foundation of China(31901597)the Natural Science Foundation of Jiangsu Province,China(BK20201243)。
文摘SrUGT76G1,the most well-studied diterpene glycosyltransferase in Stevia rebaudiana,is key to the biosynthesis of economically important steviol glycosides(SGs).However,the molecular regulatory mechanism of SrUGT76G1 has rarely been explored.In this study,we identified a MYB transcription factor,SrMYB1,using a yeast one-hybrid screening assay.SrMYB1 belongs to the typical R2R3-type MYB protein and is specifically localized in the nucleus with strong transactivation activity.The transcript of SrMYB1 is predominantly accumulated in flowers,but is also present at a lower level in leaves.Yeast one-hybrid and electrophoretic mobility shift assays verified that SrMYB1 binds directly to the MYB binding sites in the F4-3 fragment(+50–(–141))of the SrUGT76G1 promoter.Furthermore,we found that SrMYB1 could significantly repress the expression of SrUGT76G1 in both epidermal cells of tobacco leaves and stevia callus.Taken together,our results demonstrate that SrMYB1 is an essential upstream regulator of SrUGT76G1 and provide novel insight into the regulatory network for the SGs metabolic pathway in S.rebaudiana.
基金supported by the National Key R&D Program of China (No. 2018YFD0901205)
文摘The factor in the germline alpha(figla), as a member of the basic helix-loop-helix family, has been reported to be involved in ovary development in mammals and teleosts. However, the regulatory mechanisms of figla in teleosts remain unclear. Here,figla in P. olivaceus(Pofigla) was characterized with encoding a 202 amino acid protein that contains a conserved basic region and helix-loop-helix(HLH) domain. Amino acids alignment and synteny analysis revealed that Pofigla was conserved with the orthologous gene sequences in other vertebrates. The results of qRT-PCR showed Pofigla was maternally inherited during embryonic development. For tissue distribution, Pofigla showed a sexually dimorphic gene expression in the gonad of different genders, with a higher expression in ovary than in testis. In situ hybridization(ISH) results demonstrated Pofigla was specifically expressed in germ cells including oocytes, spermatogonia and spermatocytes. By screening and analyzing two proximal regions(-2966/-2126 and-772/-444) with high promoter activity, we found SOX5, LEF1, FOXP1 and GATA1 may play important roles in the transcriptional regulation of Pofigla. Furthermore, we observed the co-localization between Figla and LEF1 in HEK 293T cells. And the significant up-regulation effect of the canonical Wnt signaling pathway on the expression of Pofigla was found in cultured ovarian cells. This study provided the first evidence that figla not only has an important function in ovary development, but also plays some potential roles in testis development and/or male germ cell differentiation during early testis development in P. olivaceus. The results provide valuable reference in exploring the regulatory network of figla in teleost.
基金National Natural Science Foundation of China (30670094,30700028)
文摘The molecular modifications of Herpes Simplex Virus Type I (HSV-1) proteins represented by acetylation and phosphorylation are essential to its biological functions. The cellular chromatin-remodeling/ assembly is involved in HSV-1 associated gene transcriptional regulation in human cells harboring HSV-1 lytic or latent infections. Further investigation on these biological events would provide a better understanding of the mechanisms of HSV-1 viral gene transcriptional regulation
基金This work was supported by the Research Foundation of Chongqing Education Committee (No. KJ070314)Innovation Foundation of Chongqing Medical University (No. CX200526)Research Foundation for Advanced Talents of Chongqing Medical Univer-sity (No. QD200316).
文摘Human X-box binding protein 1 (XBP1), an important transcription factor, participates in many signal transduction processes. To further investigate the biological function of XBP1, sequences of XBP1 promoter and its two deletion mutants were first determined using bioinformatic analysis. The report vectors containing XBP1 promoter and its deletion mutants were then constructed, namely, p1-XBPlp, p2-XBPlp, and p3-XBPlp. Each reporter vector was separately transfected into HepG2, L02, K562, SMMC-7721, HSF, and Lipocyte lto Cell line using FuGENE 6 transfection reagents. The activity of chloramphenicol acetyltransferase (CAT) in each group of transfected cells was detected by ELISA assay, which in turn reflects the transcription activity of the XBP1 gene promoter. The activity involving p3-XBPlp was the highest in HepG2, which was 12.4-fold of that of pCAT3-Basic. The activities of p3-XBPlp in K562 and SMMC-7721 were the second and the third highest, which were 10.9-fold and 10.0-fold of that of the pCAT3-Basic, respectively. The CAT activity in L02 was lower than that in the above-mentioned abnormal cell, and no reporter activity was detected in HSF and Ito Cell. The XBP1 transcription and expression in K562, HepG2 and SMMC-7721 were found to be higher than that in L02, HSF and Ito cells, based on the results of real-time RT-PCR and Western blot. The XBP1 transcription and expression in L02, HSF was lower, whereas that in Ito cells was totally lacking. The result was similar to that of CAT-ELISA. Therefore, the XBP1 gene promoter can drive its downstream gene expression and its activity is cell line-dependent. The core sequence of XBP1 promoter was found between -227bp and 66bp sequence. This sequence was closely associated with the transcriptional activity of XBP1 promoter.
基金grants to Jing De Zhu from the Shanghai Science Foundation (04DZ14006 , 05DZ19318) the National Science Foundation (30450001, 30570850 , 10574134) the National Research Program for Basic Research of China (2004CB518804 , 2002CB713700).
文摘The hepatocellular carcinoma suppressor 1 (HCCS1) gene was identified by both positional cloning from a predominant region of loss of heterozygosity (17p 13.3) in liver cancer and by functional screening for genes affecting cell proliferation in large-scale transfection assays. Its overexpression results in inhibition of cell proliferation in cell culture and tumor growth in nude mice. To understand its transcription regulation, the promoter architecture has been dissected in detail. The major start of transcription was mapped by primer extension to a C residue, 177 nucleotides upstream of the ATG codon. By assessing the promoter activity of a set of linker-scanning mutants of the minimal promoter (-60 to +148 region) in a transient transfection assay, we found that the +1 to + 40 region is critical to HCCS1 gene transcription, containing binding sites for transcription factors NF-kB (-21 to +7 and +40 to +26), p53 (+29 to +9) and ETS (+4 to +20 and +23 to +39). Biochemical and molecular analyses revealed that the ETS transcription factors ETS-2 and Elf-1 bind to the two ETS sites in situ and contribute significantly to the transcriptionally active state of the HCCS1 gene, while NF-kB, p53 and two other members of the ETS family (ETS-1 and NERF2) appear to play little role. Our observations provide insight into the mechanistic aspects of HCCS1 transcription regulation.
文摘To clone and identify the proteins involved in regulating the transcription of hTERT and study the role of genes in both hTERT transcription and telomerase activity. Methods The full cDNA of COUP-TFII was cloned from HeLa cDNA library by hTERT promoter-based yeast one-hybrid assay and then in-frame inserted into His-tag fusion expression vector pEK318. The His-tag COUP-TFII fusion proteins were purified by Ni-NTA chromatography. The interaction of COUP-TFII with hTERT promoter in vitro was identified by electrophoretic mobility shift assay and Footprint. The role of COUP-TFII in both hTERT transcription and telomerase activity were probed through Luciferase reporter assay, Northern blot, and TRAP-PCR ELISA. Results COUP-TFII could firmly bind to the downstream E-box and the other two binding sites in hTERT promoter. Luciferase reporter assay indicated COUP-TFII could suppress hTERT promoter activity and stable introduction of COUP-TFII into HeLa cells also decreased both endogenous hTERT transcription and telomerase activity. Conclusion The human COUP-TFII can firmly bind to hTERT promoter, and inhibit telomerase activity through decreasing hTERT transcription. It will greatly facilitate understanding of telomerase regulation in normal and cancer cells
基金This work is supported by the 973 projects of China (G1998051004) to Jingde Zhu and (G199805l200) to Dafang Wan, respectively.Thanks are due to Hongyu Zhang and other mem-bers in Jingde Zhu's lab for assistance and helps onnumerous occasions.
文摘The human RNA methyltransferase like 1 gene (RNMTL1) is one of thirteen newly discovered genes within a 116 Kb segment of the chromosome 17pl3.3 that suffers from a high frequent loss of heterozygosity in human hepatocellular carcinoma in China[1-5]. To understand the molecular mechanisms underlying transcription control of the RNMTL1 gene in human cancers, we decline using of the conventional approach where the cis-elements bound by the known transcription factors are primary targets, and carried out the systematic analyses to dissect the promoter structure and identify/characterize the key cis-elements that are responsible for its strong expression in cell. The molecular approaches applied included 1, the primer extension for mapping of the transcription starts; 2, the transient transfection/reporter assays on a large number of deletion and site-specific mutants of the promoter segment for defining the minimal promoter and the crucial elements within; and 3, the electrophoresis mobility shift assay with specific antibodies for reconfirming the nature of the transcription factors and their cognate cis-elements. We have shown that the interaction of an ATF/CREB element (-38 to -31) and its cognate transcription factors play a predominant role in the promoter activity of the RNMTL1 gene. The secondary DNA structures of the ATF/CREB element play a more vital role in the protein-DNA interaction. Finally, we reported a novel mechanism underlying the YY1 mediated transcription repression, namely, the ATF/CREB dependent transcription-repression by YY1 is executed in absence of its own sequence-specific binding.
基金supported by the Start-up Funding of Henan University of Science and Technology(13480027) to Q. C.the Key Science Foundation of Nanjing Medical University(2015NJMUZD002)+2 种基金the Natural Science Foundation of Higher Education Institutions of Jiangsu Province(16KJB-180020)Natural Science Foundation of Jiangsu Province (BK20171053)National Natural Science Funds of China (81702747) to C.L
文摘Kruppel-like factor 4(Klf4) is a zinc finger transcription factor and plays crucial roles in Xenopus embryogenesis.However, its regulation during embryogenesis is still unclear. Here, we report that Tcf711, a key downstream transducer of the Wnt signaling pathway, could promote Klf4 transcription and stimulate Klf4 promoter activity in early Xenopus embryos. Furthermore, cycloheximide treatment showed a direct effect on Klf4 transcription facilitated by Tcf711. Moreover, the dominant negative form of Tcf711(dnTcf711), which lacks N-terminus of the β-catenin binding motif, could still activate Klf4 transcription, suggesting that this regulation is Wnt/β-catenin independent.Taken together, our results demonstrate that Tcf711 lies upstream of Klf4 to maintain its expression level during Xenopus embryogenesis.