The ability of wheat to adapt to a wide range of environmental conditions is determined mostly by allelic diversity among genes regulating vernalization requirement.Vrn-1 is a major regulator of this requirement.In th...The ability of wheat to adapt to a wide range of environmental conditions is determined mostly by allelic diversity among genes regulating vernalization requirement.Vrn-1 is a major regulator of this requirement.In this study,two novel alleles of Vrn-A1 were discovered in Chinese cultivars:vrn-A1n was identified in two landraces,Jiunong 2 and Ganchun 16,and Vrn-A1o was detected in Duanhongmangmai.Both novel alleles showed a linked duplication in the promoter region.The common copy of these two alleles was identical to the recessive allele vrn-A1.Compared with the recessive allele vrn-A1,the other copy of vrn-A1n contained a 54-bp deletion in the promoter region and the distinct copy of Vrn-A1o contained an11-bp deletion in the promoter region.In segregating populations in the greenhouse under nonvernalizing(20–25°C)and long-day(16 h light)conditions,plants with the novel vrn-A1n allele did not head earlier than those with the recessive vrn-A1 allele.However,plants that were either homozygous or heterozygous for the novel Vrn-A1o allele headed earlier than those with the recessive vrn-A1 allele.To identify the novel allele with the small-sized product and facilitate screening,a DNA marker for the novel dominant allele Vrn-A1o was designed.Analysis of the novel-allele distribution showed that two cultivars carrying the vrn-A1n allele were dispersed in the northwestern spring wheat zone,and 12 cultivars carrying the dominant Vrn-A1o allele were widely distributed in the northwestern spring wheat zone,Xinjiang winter and spring wheat zone,Yellow and Huai River valley winter wheat zone,and QinghaiTibetan Plateau spring and winter wheat zone.Our study identifies useful germplasm and a DNA marker for wheat breeding.展开更多
The turnip(Brassica rapa var. rapa) is a biennial crop that is planted in late summer/early fall and forms fleshy tubers for food in temperate regions. The harvested tubers then overwinter and are planted again the ne...The turnip(Brassica rapa var. rapa) is a biennial crop that is planted in late summer/early fall and forms fleshy tubers for food in temperate regions. The harvested tubers then overwinter and are planted again the next spring for flowering and seeds. FLOWERING LOCUS C(FLC) is a MADS-box transcription factor that acts as a major repressor of floral transition by suppressing the flowering promoters FT and SOC1. Here we show that vernalization effectively represses tuber formation and promotes flowering in Tibetan turnip. We functionally characterized four FLC homologues(BrrFLC1,FLC2, FLC3, and FLC5), and found that BrrFLC2 and BrrFLC1 play a major role in repressing flowering in turnip and in transgenic Arabidopsis. In contrast, tuber formation was correlated with BrrFLC1 expression in the hypocotyl and was repressed under cold treatment following the quantitative downregulation of BrrFLC1. Grafting experiments of non-vernalized and vernalized turnips revealed that vernalization independently suppressed tuberization in the tuber or hypocotyl of the rootstock or scion, which occurred in parallel with the reduction in BrrFLC1 activity. Together, our results demonstrate that the Tibetan turnip is highly responsive to cold exposure, which is associated with the expression levels of BrrFLC genes.展开更多
The effects of BCG PSN on T cell subsets and cytokines in vernal conjunctivitis were observed. The level of total IgE was quantitatively determined before and after treatment with BCG PSN by allergen diagnostic instru...The effects of BCG PSN on T cell subsets and cytokines in vernal conjunctivitis were observed. The level of total IgE was quantitatively determined before and after treatment with BCG PSN by allergen diagnostic instrument in vitro . The content of T cell subsets of peripheral blood and cytokine were determined by using indirect immune fluorescence method, and IL 4 and INF γ were quantified by ELISA. The results showed that the level of total IgE was substantially reduced ( P <0.01) after treatment in the BCG PSN group. Meanwhile, CD + 8 was decreased, CD + 4 and CD + 4/CD + 8 ratio elevated with significant differences ( P <0.05) as compared with pre treatment results. The changes in total IgE, CD + 8 ,CD + 4 and CD + 4/CD + 8 ratio after treatment also presented significant differences ( P <0.05) between BCG PSN group and routine treatment group. The level of IL 4 in serum declined ( P <0.05) after treatment in the BCG PSN group, and INF γ went up ( P <0 05). IL 4 and INF γ in serum showed significant differences ( P <0.05) between two groups after treatment. It is concluded that BCG PSN has a bi directional immunoregulating effect. It can bring CD + 4 and CD + 8 into homeostasis, thereby preventing the occurrence of anaphylaxis. At the same time, BCG PSN can restrain Th 2, decrease the synthesis of IL 4, switch the balance of Th l/Th 2 to Th 1 side, boost up the predominance of Th 1 relatively, which is propitious to perennial stabilization and recovery of vernal conjunctivitis.展开更多
AIM: To demonstrate the effects of two different types of allergic conjunctivitis on severity of keratoconus (KC). ·METHODS: We retrospectively reviewed the medical records of 171 KC patients referred between Jun...AIM: To demonstrate the effects of two different types of allergic conjunctivitis on severity of keratoconus (KC). ·METHODS: We retrospectively reviewed the medical records of 171 KC patients referred between June 2010 and June 2011. The KC patients were divided into 3 groups as KC (group A), KC with vernal keratoconjunctivitis (VKC) (group B) and KC with allergic conjunctivitis (AC) (group C). Main outcome measures were demographic and ocular clinical features including age at presentation, gender, spherical equivalent (SE), best spectacle corrected visual acuity (BCVA), mean keratometric measurement (Km), central corneal thickness (CCT), and intraocular pressure (IOP). Groups were compared in term of study variables. · RESULTS: The median age at presentation was significantly lower in group B (P <0.001). According to the median SE (P =0.003), BCVA(P =0.022), Km(P <0.001), CCT (P =0.015) and Amsler-Krumeich classification (P < 0.001), KC was more severe in group B. There was no significant difference in terms of IOP and corrected IOP among the groups (P =0.44), however there were 4 patients who had increased corrected IOP developed after topical corticosteroid use in group B. The differences among the groups persisted even after controlling for age and gender. · CONCLUSION: Our findings demonstrated a more severe KC in VKC patients despite their younger age which suggests evaluation of VKC patients as a separate group in keratoconus disease.展开更多
MicroRNA396(miR396)has been demonstrated to regulate flower development by targeting growth-regulating factors(GRFs)in annual species.However,its role in perennial grasses and its potential involvement in flowering ti...MicroRNA396(miR396)has been demonstrated to regulate flower development by targeting growth-regulating factors(GRFs)in annual species.However,its role in perennial grasses and its potential involvement in flowering time control remain unexplored.Here we report that overexpression of miR396 in a perennial species,creeping bentgrass(Agrostis stolonifera L.),alters flower development.Most significantly,transgenic(TG)plants bypass the vernalization requirement for flowering.Gene expression analysis reveals that miR396 is induced by long-day(LD)photoperiod and vernalization.Further study identifies VRN1,VRN2,and VRN3 homologs whose expression patterns in wild-type(WT)plants are similar to those observed in wheat and barley during transition from short-day(SD)to LD,and SD to cold conditions.However,compared to WT controls,TG plants overexpressing miR396 exhibit significantly enhanced VRN1 and VRN3 expression,but repressed VRN2 expression under SD to LD conditions without vernalization,which might be associated with modified expression of methyltransferase genes.Collectively,our results unveil a potentially novel mechanism by which miR396 suppresses the vernalization requirement for flowering which might be related to the epigenetic regulation of VRN genes and provide important new insight into critical roles of a miRNA in regulating vernalization-mediated transition from vegetative to reproductive growth in monocots.展开更多
Background: Data on the serum vitamin D3 levels of vernal keratoconjunctivitis (VKC) children are not known well in Central Africa. Children with vernal keratoconjunctivitis are less exposed to sunlight. There is no s...Background: Data on the serum vitamin D3 levels of vernal keratoconjunctivitis (VKC) children are not known well in Central Africa. Children with vernal keratoconjunctivitis are less exposed to sunlight. There is no study that shows the breadth of the serum vitamin D3 levels of vernal keratoconjunctivitis children and normal in our setting. Purpose: This study aimed to compare the serum 25-hydroxy vitamin D [25(OH)D3] levels of children with and without VKC. Methods: An observational, case-control study was performed from September 2019 to February 2020 in the Ophthalmology Department and the Clinical Biology Department of the University Hospital of Kinshasa. The case group was recruited consecutively in the consultation while the control group was enrolled in the nearest Rehoboth school complex using a systematic sample method (k = 4) on the presence register. Both cases and controls underwent the routine ophthalmological examination of the anterior segment and serum vitamin D3 levels were measured in both cases and controls using Mindray Chimic-Luminescence (CL)-1200i. Data were entered in Microsoft Sheets and analyzed using SPSS version 20.0. The Mann-Whitney-U test (M-U), and the t-Student test were used respectively to compare the mean serum vitamin D3 levels in both cases and controls. The correlation of Spearman (rho) was used to determine the association between Body Mass Index and serum vitamin D3 levels in the case group. Results: A total of 75 children with VKC (mean age 7.8 ± 4.4 years) and 75 children without VKC non-atopic control group (mean age 7.9 ± 4.3 years) were enrolled in this study. The vitamin D3 deficiency was more frequent among the case group than in the control group (40% vs 8%, p = 0.0001). Vitamin D3 insufficiency was more frequent in the case group than in the control group (33.3% vs 18.6%, p = 0.04). The mean serum vitamin 25(OH)D3 levels were statistically lower in children with VKC compared to those without (25.5 ± 8.7 ng/ml and 44.3 ± 18.5 ng/ml, p = 0.0001). Time spent outdoors during daylight by children with VKC was statistically lower than children without VKC (1.59 ± 0.71 hours and 2.28 ± 1.08 hours, respectively) (p = 0.0001). Body Mass Index and serum vitamin D3 levels in VKC children showed a negative correlation statistically significant (Spearman, rho = -0.452, p = 0.0001). Conclusion: This study showed statistically values of serum vitamin D3 levels in VKC children lower than in children without VKC.展开更多
The relationship between vernalization requirement and quantitative and qualitative changes in total leaf soluble proteins were determined in one spring(cv.Kohdasht) and two winter(cvs.Sardari and Norstar) cultivars o...The relationship between vernalization requirement and quantitative and qualitative changes in total leaf soluble proteins were determined in one spring(cv.Kohdasht) and two winter(cvs.Sardari and Norstar) cultivars of wheat(Triticum aestivum L.) exposed to 4°C.Plants were sampled on days 2,14,21 and 35 of exposure to 4°C.The final leaf number(FLN) was determined throughout the vernalization periods(0,7,14,24,and 35 d) at 4°C.The final leaf number decreased until days 24 and 35 in Sardari and Norstar cultivars,respectively,indicating the vernalization saturation at these times.No clear changes were detected in the final leaf number of Kohdash cultivar,verifying no vernalization requirement for this spring wheat cultivar.Comparing with control,clear cold-induced 2-fold increases in proteins quantity occurred after 48 h following the 4°C-treatment in the leaves of the both winter wheat cultivars but,such response was not detected in the spring cultivar.However,the electrophoretic protein patterns showed between-cultivar and between-temperature treatment differences.With increasing exposure time to 4°C,the winter cultivars tended to produce more HMW polypeptides than the spring cultivar.Similar proteins were induced in both Sardari and Norstar winter wheat cultivars,however,the long vernalization requirement in Norstar resulted in high level and longer duration of expression of cold-induced proteins compared to Sardari with a short vernalization requirement.These observations indicate that vernalization response regulates the expression of low temperature(LT) tolerance proteins and determines the duration of expression of LT-induced proteins.展开更多
Spring wheat (cv. 7742) and winter wheat (cv. Nongda 015) were vernalized by seed chilling, and the changes of GAs, ABA content and GAs / ABA ratio in embryo were investigated. The differences between cultivars, treat...Spring wheat (cv. 7742) and winter wheat (cv. Nongda 015) were vernalized by seed chilling, and the changes of GAs, ABA content and GAs / ABA ratio in embryo were investigated. The differences between cultivars, treatments and variety-treatment interactions were significant for both GAs and ABA. The level of GAs and ABA as well as GAs / ABA ratio were hardly changed by seed chilling in spriug wheat However, in winter wheat, the GAs content decreased much less compared with ABA that reduced sharply after chilling. It showed that the GAs / ABA ratio in winter wheat was increased remarkably (4.55 times) than in spring wheat. It was suggested that the absolute GAs level was independent of the vernalization effect because there was a higher GAs level before and after seed chilling in winter wheat when compared with spring wheat, One of the vemalization effects was the decline of ABA level that led to the increase of GAs / ABA ratio.展开更多
To evaluate the efficacy and safety of resection and cryotherapy combined with amniotic membrane transplantation (AMT) for the treatment of vernal keratoconjunctivitis (VKC) with giant papillae (GP). Eight patients (1...To evaluate the efficacy and safety of resection and cryotherapy combined with amniotic membrane transplantation (AMT) for the treatment of vernal keratoconjunctivitis (VKC) with giant papillae (GP). Eight patients (16 eyes involved) with VKC, characterized by GP on the upper tarsal conjunctiva, underwent resection and cryotherapy in combination with AMT. The follow-up lasted for 3-22 months. The results showed that corneal shield ulcers and superficial punctuate keratitis healed during the first week after surgery and did not recur. Fourteen eyes (87.5 %) were symptom-free 1 month after surgery, and no GP, ectropion, trichiasis and other complications were noted, but the blood vessels of upper tarsal conjunctiva could not be clearly seen and a little conjunctival scar was observed. Recurrence of GP was observed in 2 eyes (12.5 %), with the area being less and irritation milder as compared with those before the operation. Among the two eyes, one eye was treated by cyclosporine eyedrops with improvement, but the other eye showed no improvement after the treatment, and underwent a second surgery with a cotton patch soaked in fluorouracil applied onto the su-pratarsal area after resection and cryotherapy. Four months after the treatment the patient presented no symptoms and GP did not recur. It is concluded that the resection and cryotherapy combined with AMT is an effective and safe treatment for VKC with GP.展开更多
An F2 population,derived from a cross between the vernalization independent genotype‘Rc Br'and the vernalization dependent genotype‘08A061',was developed to construct a linkage map with 165 SSR and In Del ma...An F2 population,derived from a cross between the vernalization independent genotype‘Rc Br'and the vernalization dependent genotype‘08A061',was developed to construct a linkage map with 165 SSR and In Del markers. QTL analysis was performed by two phenotypic evaluation( days to 5 cm elongate stalk and flowering time) based on the difference in F2: 3families under vernalization and no vernalization. The results showed that the vernalization requirement was recessive in Brassica rapa. Seven QTLs that controlled vernalization requirement were detected on A02 and A06 linkage groups,which explained phenotypic variation ranging from 0. 08% to 22. 52%. Two QTLs( VR-DE01,VR-FT01) were detected on the top of A02,which explained 22. 52% and 14. 54% of the phenotypic variation,respectively,and closely linked with Br FLC2 gene. Two QTLs( VR-DE03,VR-DE04) were detected on A06 with 13. 30% and 13. 64% of phenotypic variation. These detected QTLs will provide useful information on understanding the genetic basis between vernalization requirement and bolting,and that will be useful for marker-assisted selection( MAS) in a breeding program for bolting resistant cultivars.展开更多
Vernalization is necessary for winter wheat to flower.However,it is unclear whether vernalization is also required for spring wheat,which is frequently sown in fall,and what molecular mechanisms underlie the vernaliza...Vernalization is necessary for winter wheat to flower.However,it is unclear whether vernalization is also required for spring wheat,which is frequently sown in fall,and what molecular mechanisms underlie the vernalization response in wheat varieties.In this study,we examined the molecular mechanisms that regulate vernalization response in winter and spring wheat varieties.For this purpose,we determined how major vernalization genes(VRN1,VRN2,and VRN3)respond to vernalization in these varieties and whether modifications to histones play a role in changes in gene expression.We also identified genes that are differentially regulated in response to vernalization in winter and spring wheat varieties.We found that in winter wheat,but not in spring wheat,VRN1 expression decreases when returned to warm temperature following vernalization.This finding may be associated with differences between spring and winter wheat in the levels of tri-methylation of lysine 27 on histone H3(H3K27me3)and tri-methylation of lysine 4 on histone H3(H3K4me3)at the VRN1 gene.Analysis of winter wheat transcriptomes before and after vernalization revealed that vernalization influences the expression of several genes,including those involved in leucine catabolism,cysteine biosynthesis,and flavonoid biosynthesis.These findings provide new candidates for further study on the mechanism of vernalization regulation in wheat.展开更多
Vernalization is a physiological process in which prolonged cold exposure establishes flowering competence in winter plants. In hexaploid wheat, TaVRN1 is a cold-induced key regulator that accelerates floral transitio...Vernalization is a physiological process in which prolonged cold exposure establishes flowering competence in winter plants. In hexaploid wheat, TaVRN1 is a cold-induced key regulator that accelerates floral transition. However, the molecular mechanism underlying the gradual activation of TaVRN1 during the vernalization process remains unknown. In this study, we identified the novel transcript VAS (TaVRN1 alternative splicing) as a non-coding RNA derived from the sense strand of the TaVRN1 gene only in winter wheat, which regulates TaVRN1 transcription for flowering. VAS was induced during the early period of vernalization, and its overexpression promoted TaVRN1 expression to accelerate flowering in winter wheat. VAS physically associates with TaRF2b and facilitates docking of the TaRF2b-TaRF2a complex at the TaVRN1 promoter during the middle period of vernalization. TaRF2b recognizes the Sp1 motif within the TaVRN1 proximal promoter region, which is gradually exposed along with the disruption of a loop structure at the TaVRN1 locus during vernalization, to activate the transcription of TaVRN1. The tarf2b mutants exhibited delayed flowering, whereas transgenic wheat lines overexpressing TaRF2b showed earlier flowering. Taken together, our data reveal a distinct regulatory mechanism by which a long non-coding RNA facilitates the transcription factor targeting to regulate wheat flowering, providing novel insights into the vernalization process and a potential target for wheat genetic improvement.展开更多
Based on the cDNA fragment sequence of vernalization-related gene verc203 cloned by differential screening in our lab, the 5′primer has been designed. The cDNA 3′end of ver203 gene (1 197 bp) has been cloned by the ...Based on the cDNA fragment sequence of vernalization-related gene verc203 cloned by differential screening in our lab, the 5′primer has been designed. The cDNA 3′end of ver203 gene (1 197 bp) has been cloned by the RACE method. And it is identified by Northern blotting that its expression is special in vernalization treatment. After comparing the sequence in the nucleotide sequence databases of Genbank, EMBL and DDBJ, the gene has homology with Hordeum vulgare jesmonate-induced protein gene. It is suggested that this gene might be related to the signal transduction mediated by jamonate.展开更多
A cDNA clone related to the vernalization in winter wheat(verc203)was harvested from the en-riched cold-induced cDNA library of 10~4 pfu with differential screening.The insert of verc203 in λ gt10 vector wassubcloned...A cDNA clone related to the vernalization in winter wheat(verc203)was harvested from the en-riched cold-induced cDNA library of 10~4 pfu with differential screening.The insert of verc203 in λ gt10 vector wassubcloned into the sites between BamH Ⅰ and Hind Ⅲ in pUC19 plasmid after being amplified with PCR.the analysis of the Northern blotting with a probe of verc203 indicated that the verc203 has a negative signalfor the control and the devernalized mRNA and a positive signal for the vernalized winter wheat and non-vernalized spring wheat at about 2.6 kb.展开更多
Vernalization is an essential factor which affects the flowering development in cold_requiring plants. There is a key stage of nucleic acid and protein metabolism in the process of vernalization in winter wheat. To pr...Vernalization is an essential factor which affects the flowering development in cold_requiring plants. There is a key stage of nucleic acid and protein metabolism in the process of vernalization in winter wheat. To probe into the molecular determinants of vernalization , we examined mRNA populations in differently_treated plumules of winter wheat \%(Triticum aestivum \%L. \%cv\% Yanda 1817) using mRNA differential display. One vernalization_ related cDNA clone \%(VRC), VRC54\%, was identified and was only expressed at the key stage of 20 d vernalization, rather than at other stages of nonvernalization, 4 d vernalization and devernalization. Northern blot and sequence analysis indicated that \%VRC54\% was a novel vernalization_related clone found in higher plant which not only might play an important role in the floral induction in vernalization_requiring plants but also was different from the cold_acclimatized genes.展开更多
The frequency and distribution of the major vernalization requirement genes and their effects on growth habits were studied.Of the 551 bread wheat genotypes tested,seven allelic combinations of the three Vrn-1 genes w...The frequency and distribution of the major vernalization requirement genes and their effects on growth habits were studied.Of the 551 bread wheat genotypes tested,seven allelic combinations of the three Vrn-1 genes were found to be responsible for the spring habit,three for the facultative habit and one for the winter habit.The three Vrn-1 genes behaved additively with the dominant allele of Vrn-A1 exerting the strongest effect.The allele combinations of the facultative genotypes and the discovery of spring genotypes with "winter" allele of Vrn-1 implied the presence of as yet unidentified alleles/genes for vernalization response.The dominant alleles of the three Vrn-1 genes were found in all ten ecological regions where wheat is cultivated in China,with Vrn-D1 as the most common allele in nine and Vrn-A1 in one.The combination of vrn-A1vrn-B1Vrn-D1 was the predominant genotype in seven of the regions.Compared with landraces,improved varieties contain a higher proportion of the spring type.This was attributed by a higher frequency of the dominant Vrn-A1 and Vrn-B1 alleles in the latter.Correlations between Vrn-1 allelic constitutions and heading date,spike length,plant type as well as cold tolerance were established.展开更多
基金funded by the National Key Research and Development Program of China(2016YFD0101802)the Key Research and Development Project of Shaanxi Province(2019ZDLNY04-05)+1 种基金the National Basic Research Program of China(2014CB138102)the National Natural Science Foundation of China(30971770 and 31671693)。
文摘The ability of wheat to adapt to a wide range of environmental conditions is determined mostly by allelic diversity among genes regulating vernalization requirement.Vrn-1 is a major regulator of this requirement.In this study,two novel alleles of Vrn-A1 were discovered in Chinese cultivars:vrn-A1n was identified in two landraces,Jiunong 2 and Ganchun 16,and Vrn-A1o was detected in Duanhongmangmai.Both novel alleles showed a linked duplication in the promoter region.The common copy of these two alleles was identical to the recessive allele vrn-A1.Compared with the recessive allele vrn-A1,the other copy of vrn-A1n contained a 54-bp deletion in the promoter region and the distinct copy of Vrn-A1o contained an11-bp deletion in the promoter region.In segregating populations in the greenhouse under nonvernalizing(20–25°C)and long-day(16 h light)conditions,plants with the novel vrn-A1n allele did not head earlier than those with the recessive vrn-A1 allele.However,plants that were either homozygous or heterozygous for the novel Vrn-A1o allele headed earlier than those with the recessive vrn-A1 allele.To identify the novel allele with the small-sized product and facilitate screening,a DNA marker for the novel dominant allele Vrn-A1o was designed.Analysis of the novel-allele distribution showed that two cultivars carrying the vrn-A1n allele were dispersed in the northwestern spring wheat zone,and 12 cultivars carrying the dominant Vrn-A1o allele were widely distributed in the northwestern spring wheat zone,Xinjiang winter and spring wheat zone,Yellow and Huai River valley winter wheat zone,and QinghaiTibetan Plateau spring and winter wheat zone.Our study identifies useful germplasm and a DNA marker for wheat breeding.
基金supported by the National Science Foundation of China(No.31500221,31590823 and 31601999)the West Light Foundation of the Chinese Academy of Sciences by XXK
文摘The turnip(Brassica rapa var. rapa) is a biennial crop that is planted in late summer/early fall and forms fleshy tubers for food in temperate regions. The harvested tubers then overwinter and are planted again the next spring for flowering and seeds. FLOWERING LOCUS C(FLC) is a MADS-box transcription factor that acts as a major repressor of floral transition by suppressing the flowering promoters FT and SOC1. Here we show that vernalization effectively represses tuber formation and promotes flowering in Tibetan turnip. We functionally characterized four FLC homologues(BrrFLC1,FLC2, FLC3, and FLC5), and found that BrrFLC2 and BrrFLC1 play a major role in repressing flowering in turnip and in transgenic Arabidopsis. In contrast, tuber formation was correlated with BrrFLC1 expression in the hypocotyl and was repressed under cold treatment following the quantitative downregulation of BrrFLC1. Grafting experiments of non-vernalized and vernalized turnips revealed that vernalization independently suppressed tuberization in the tuber or hypocotyl of the rootstock or scion, which occurred in parallel with the reduction in BrrFLC1 activity. Together, our results demonstrate that the Tibetan turnip is highly responsive to cold exposure, which is associated with the expression levels of BrrFLC genes.
文摘The effects of BCG PSN on T cell subsets and cytokines in vernal conjunctivitis were observed. The level of total IgE was quantitatively determined before and after treatment with BCG PSN by allergen diagnostic instrument in vitro . The content of T cell subsets of peripheral blood and cytokine were determined by using indirect immune fluorescence method, and IL 4 and INF γ were quantified by ELISA. The results showed that the level of total IgE was substantially reduced ( P <0.01) after treatment in the BCG PSN group. Meanwhile, CD + 8 was decreased, CD + 4 and CD + 4/CD + 8 ratio elevated with significant differences ( P <0.05) as compared with pre treatment results. The changes in total IgE, CD + 8 ,CD + 4 and CD + 4/CD + 8 ratio after treatment also presented significant differences ( P <0.05) between BCG PSN group and routine treatment group. The level of IL 4 in serum declined ( P <0.05) after treatment in the BCG PSN group, and INF γ went up ( P <0 05). IL 4 and INF γ in serum showed significant differences ( P <0.05) between two groups after treatment. It is concluded that BCG PSN has a bi directional immunoregulating effect. It can bring CD + 4 and CD + 8 into homeostasis, thereby preventing the occurrence of anaphylaxis. At the same time, BCG PSN can restrain Th 2, decrease the synthesis of IL 4, switch the balance of Th l/Th 2 to Th 1 side, boost up the predominance of Th 1 relatively, which is propitious to perennial stabilization and recovery of vernal conjunctivitis.
文摘AIM: To demonstrate the effects of two different types of allergic conjunctivitis on severity of keratoconus (KC). ·METHODS: We retrospectively reviewed the medical records of 171 KC patients referred between June 2010 and June 2011. The KC patients were divided into 3 groups as KC (group A), KC with vernal keratoconjunctivitis (VKC) (group B) and KC with allergic conjunctivitis (AC) (group C). Main outcome measures were demographic and ocular clinical features including age at presentation, gender, spherical equivalent (SE), best spectacle corrected visual acuity (BCVA), mean keratometric measurement (Km), central corneal thickness (CCT), and intraocular pressure (IOP). Groups were compared in term of study variables. · RESULTS: The median age at presentation was significantly lower in group B (P <0.001). According to the median SE (P =0.003), BCVA(P =0.022), Km(P <0.001), CCT (P =0.015) and Amsler-Krumeich classification (P < 0.001), KC was more severe in group B. There was no significant difference in terms of IOP and corrected IOP among the groups (P =0.44), however there were 4 patients who had increased corrected IOP developed after topical corticosteroid use in group B. The differences among the groups persisted even after controlling for age and gender. · CONCLUSION: Our findings demonstrated a more severe KC in VKC patients despite their younger age which suggests evaluation of VKC patients as a separate group in keratoconus disease.
基金supported in part by Biotechnology Risk Assessment Grant Program competitive grant no.2019-33522-30102 from the USDA and National Institute of Food and Agriculture and the United States Golf Association,Inc.grant no.2016-25-575 as well as the Sichuan Science and Technology Program grant no.2019YFH0064.
文摘MicroRNA396(miR396)has been demonstrated to regulate flower development by targeting growth-regulating factors(GRFs)in annual species.However,its role in perennial grasses and its potential involvement in flowering time control remain unexplored.Here we report that overexpression of miR396 in a perennial species,creeping bentgrass(Agrostis stolonifera L.),alters flower development.Most significantly,transgenic(TG)plants bypass the vernalization requirement for flowering.Gene expression analysis reveals that miR396 is induced by long-day(LD)photoperiod and vernalization.Further study identifies VRN1,VRN2,and VRN3 homologs whose expression patterns in wild-type(WT)plants are similar to those observed in wheat and barley during transition from short-day(SD)to LD,and SD to cold conditions.However,compared to WT controls,TG plants overexpressing miR396 exhibit significantly enhanced VRN1 and VRN3 expression,but repressed VRN2 expression under SD to LD conditions without vernalization,which might be associated with modified expression of methyltransferase genes.Collectively,our results unveil a potentially novel mechanism by which miR396 suppresses the vernalization requirement for flowering which might be related to the epigenetic regulation of VRN genes and provide important new insight into critical roles of a miRNA in regulating vernalization-mediated transition from vegetative to reproductive growth in monocots.
文摘Background: Data on the serum vitamin D3 levels of vernal keratoconjunctivitis (VKC) children are not known well in Central Africa. Children with vernal keratoconjunctivitis are less exposed to sunlight. There is no study that shows the breadth of the serum vitamin D3 levels of vernal keratoconjunctivitis children and normal in our setting. Purpose: This study aimed to compare the serum 25-hydroxy vitamin D [25(OH)D3] levels of children with and without VKC. Methods: An observational, case-control study was performed from September 2019 to February 2020 in the Ophthalmology Department and the Clinical Biology Department of the University Hospital of Kinshasa. The case group was recruited consecutively in the consultation while the control group was enrolled in the nearest Rehoboth school complex using a systematic sample method (k = 4) on the presence register. Both cases and controls underwent the routine ophthalmological examination of the anterior segment and serum vitamin D3 levels were measured in both cases and controls using Mindray Chimic-Luminescence (CL)-1200i. Data were entered in Microsoft Sheets and analyzed using SPSS version 20.0. The Mann-Whitney-U test (M-U), and the t-Student test were used respectively to compare the mean serum vitamin D3 levels in both cases and controls. The correlation of Spearman (rho) was used to determine the association between Body Mass Index and serum vitamin D3 levels in the case group. Results: A total of 75 children with VKC (mean age 7.8 ± 4.4 years) and 75 children without VKC non-atopic control group (mean age 7.9 ± 4.3 years) were enrolled in this study. The vitamin D3 deficiency was more frequent among the case group than in the control group (40% vs 8%, p = 0.0001). Vitamin D3 insufficiency was more frequent in the case group than in the control group (33.3% vs 18.6%, p = 0.04). The mean serum vitamin 25(OH)D3 levels were statistically lower in children with VKC compared to those without (25.5 ± 8.7 ng/ml and 44.3 ± 18.5 ng/ml, p = 0.0001). Time spent outdoors during daylight by children with VKC was statistically lower than children without VKC (1.59 ± 0.71 hours and 2.28 ± 1.08 hours, respectively) (p = 0.0001). Body Mass Index and serum vitamin D3 levels in VKC children showed a negative correlation statistically significant (Spearman, rho = -0.452, p = 0.0001). Conclusion: This study showed statistically values of serum vitamin D3 levels in VKC children lower than in children without VKC.
基金financially supported by a grant from Tarbiat Modares University,Tehran,Iran
文摘The relationship between vernalization requirement and quantitative and qualitative changes in total leaf soluble proteins were determined in one spring(cv.Kohdasht) and two winter(cvs.Sardari and Norstar) cultivars of wheat(Triticum aestivum L.) exposed to 4°C.Plants were sampled on days 2,14,21 and 35 of exposure to 4°C.The final leaf number(FLN) was determined throughout the vernalization periods(0,7,14,24,and 35 d) at 4°C.The final leaf number decreased until days 24 and 35 in Sardari and Norstar cultivars,respectively,indicating the vernalization saturation at these times.No clear changes were detected in the final leaf number of Kohdash cultivar,verifying no vernalization requirement for this spring wheat cultivar.Comparing with control,clear cold-induced 2-fold increases in proteins quantity occurred after 48 h following the 4°C-treatment in the leaves of the both winter wheat cultivars but,such response was not detected in the spring cultivar.However,the electrophoretic protein patterns showed between-cultivar and between-temperature treatment differences.With increasing exposure time to 4°C,the winter cultivars tended to produce more HMW polypeptides than the spring cultivar.Similar proteins were induced in both Sardari and Norstar winter wheat cultivars,however,the long vernalization requirement in Norstar resulted in high level and longer duration of expression of cold-induced proteins compared to Sardari with a short vernalization requirement.These observations indicate that vernalization response regulates the expression of low temperature(LT) tolerance proteins and determines the duration of expression of LT-induced proteins.
文摘Spring wheat (cv. 7742) and winter wheat (cv. Nongda 015) were vernalized by seed chilling, and the changes of GAs, ABA content and GAs / ABA ratio in embryo were investigated. The differences between cultivars, treatments and variety-treatment interactions were significant for both GAs and ABA. The level of GAs and ABA as well as GAs / ABA ratio were hardly changed by seed chilling in spriug wheat However, in winter wheat, the GAs content decreased much less compared with ABA that reduced sharply after chilling. It showed that the GAs / ABA ratio in winter wheat was increased remarkably (4.55 times) than in spring wheat. It was suggested that the absolute GAs level was independent of the vernalization effect because there was a higher GAs level before and after seed chilling in winter wheat when compared with spring wheat, One of the vemalization effects was the decline of ABA level that led to the increase of GAs / ABA ratio.
文摘To evaluate the efficacy and safety of resection and cryotherapy combined with amniotic membrane transplantation (AMT) for the treatment of vernal keratoconjunctivitis (VKC) with giant papillae (GP). Eight patients (16 eyes involved) with VKC, characterized by GP on the upper tarsal conjunctiva, underwent resection and cryotherapy in combination with AMT. The follow-up lasted for 3-22 months. The results showed that corneal shield ulcers and superficial punctuate keratitis healed during the first week after surgery and did not recur. Fourteen eyes (87.5 %) were symptom-free 1 month after surgery, and no GP, ectropion, trichiasis and other complications were noted, but the blood vessels of upper tarsal conjunctiva could not be clearly seen and a little conjunctival scar was observed. Recurrence of GP was observed in 2 eyes (12.5 %), with the area being less and irritation milder as compared with those before the operation. Among the two eyes, one eye was treated by cyclosporine eyedrops with improvement, but the other eye showed no improvement after the treatment, and underwent a second surgery with a cotton patch soaked in fluorouracil applied onto the su-pratarsal area after resection and cryotherapy. Four months after the treatment the patient presented no symptoms and GP did not recur. It is concluded that the resection and cryotherapy combined with AMT is an effective and safe treatment for VKC with GP.
基金Supported by the National Natural Science Foundation of China(30900981)the Research Program of the Educational Department of Liaoning Province(L2013255)
文摘An F2 population,derived from a cross between the vernalization independent genotype‘Rc Br'and the vernalization dependent genotype‘08A061',was developed to construct a linkage map with 165 SSR and In Del markers. QTL analysis was performed by two phenotypic evaluation( days to 5 cm elongate stalk and flowering time) based on the difference in F2: 3families under vernalization and no vernalization. The results showed that the vernalization requirement was recessive in Brassica rapa. Seven QTLs that controlled vernalization requirement were detected on A02 and A06 linkage groups,which explained phenotypic variation ranging from 0. 08% to 22. 52%. Two QTLs( VR-DE01,VR-FT01) were detected on the top of A02,which explained 22. 52% and 14. 54% of the phenotypic variation,respectively,and closely linked with Br FLC2 gene. Two QTLs( VR-DE03,VR-DE04) were detected on A06 with 13. 30% and 13. 64% of phenotypic variation. These detected QTLs will provide useful information on understanding the genetic basis between vernalization requirement and bolting,and that will be useful for marker-assisted selection( MAS) in a breeding program for bolting resistant cultivars.
基金supported by Project 2662020ZKPY002 supported by the Fundamental Research Funds for the Central Universities.
文摘Vernalization is necessary for winter wheat to flower.However,it is unclear whether vernalization is also required for spring wheat,which is frequently sown in fall,and what molecular mechanisms underlie the vernalization response in wheat varieties.In this study,we examined the molecular mechanisms that regulate vernalization response in winter and spring wheat varieties.For this purpose,we determined how major vernalization genes(VRN1,VRN2,and VRN3)respond to vernalization in these varieties and whether modifications to histones play a role in changes in gene expression.We also identified genes that are differentially regulated in response to vernalization in winter and spring wheat varieties.We found that in winter wheat,but not in spring wheat,VRN1 expression decreases when returned to warm temperature following vernalization.This finding may be associated with differences between spring and winter wheat in the levels of tri-methylation of lysine 27 on histone H3(H3K27me3)and tri-methylation of lysine 4 on histone H3(H3K4me3)at the VRN1 gene.Analysis of winter wheat transcriptomes before and after vernalization revealed that vernalization influences the expression of several genes,including those involved in leucine catabolism,cysteine biosynthesis,and flavonoid biosynthesis.These findings provide new candidates for further study on the mechanism of vernalization regulation in wheat.
基金We gratefully ack no wledge funding from the NSFC for the Basic Scie nee Center Program(31788103)the National Natural Science Foundation of China(31970529)the China Postdoctoral Science Foundation(2019M650892).
文摘Vernalization is a physiological process in which prolonged cold exposure establishes flowering competence in winter plants. In hexaploid wheat, TaVRN1 is a cold-induced key regulator that accelerates floral transition. However, the molecular mechanism underlying the gradual activation of TaVRN1 during the vernalization process remains unknown. In this study, we identified the novel transcript VAS (TaVRN1 alternative splicing) as a non-coding RNA derived from the sense strand of the TaVRN1 gene only in winter wheat, which regulates TaVRN1 transcription for flowering. VAS was induced during the early period of vernalization, and its overexpression promoted TaVRN1 expression to accelerate flowering in winter wheat. VAS physically associates with TaRF2b and facilitates docking of the TaRF2b-TaRF2a complex at the TaVRN1 promoter during the middle period of vernalization. TaRF2b recognizes the Sp1 motif within the TaVRN1 proximal promoter region, which is gradually exposed along with the disruption of a loop structure at the TaVRN1 locus during vernalization, to activate the transcription of TaVRN1. The tarf2b mutants exhibited delayed flowering, whereas transgenic wheat lines overexpressing TaRF2b showed earlier flowering. Taken together, our data reveal a distinct regulatory mechanism by which a long non-coding RNA facilitates the transcription factor targeting to regulate wheat flowering, providing novel insights into the vernalization process and a potential target for wheat genetic improvement.
文摘Based on the cDNA fragment sequence of vernalization-related gene verc203 cloned by differential screening in our lab, the 5′primer has been designed. The cDNA 3′end of ver203 gene (1 197 bp) has been cloned by the RACE method. And it is identified by Northern blotting that its expression is special in vernalization treatment. After comparing the sequence in the nucleotide sequence databases of Genbank, EMBL and DDBJ, the gene has homology with Hordeum vulgare jesmonate-induced protein gene. It is suggested that this gene might be related to the signal transduction mediated by jamonate.
基金the National Natural Science Foundation of China
文摘A cDNA clone related to the vernalization in winter wheat(verc203)was harvested from the en-riched cold-induced cDNA library of 10~4 pfu with differential screening.The insert of verc203 in λ gt10 vector wassubcloned into the sites between BamH Ⅰ and Hind Ⅲ in pUC19 plasmid after being amplified with PCR.the analysis of the Northern blotting with a probe of verc203 indicated that the verc203 has a negative signalfor the control and the devernalized mRNA and a positive signal for the vernalized winter wheat and non-vernalized spring wheat at about 2.6 kb.
文摘Vernalization is an essential factor which affects the flowering development in cold_requiring plants. There is a key stage of nucleic acid and protein metabolism in the process of vernalization in winter wheat. To probe into the molecular determinants of vernalization , we examined mRNA populations in differently_treated plumules of winter wheat \%(Triticum aestivum \%L. \%cv\% Yanda 1817) using mRNA differential display. One vernalization_ related cDNA clone \%(VRC), VRC54\%, was identified and was only expressed at the key stage of 20 d vernalization, rather than at other stages of nonvernalization, 4 d vernalization and devernalization. Northern blot and sequence analysis indicated that \%VRC54\% was a novel vernalization_related clone found in higher plant which not only might play an important role in the floral induction in vernalization_requiring plants but also was different from the cold_acclimatized genes.
基金Supported by the State Key Basic Research and Development Plan ofChina (2004CB117200)Germplasm Conservation Project from Ministryof Agriculture.
文摘The frequency and distribution of the major vernalization requirement genes and their effects on growth habits were studied.Of the 551 bread wheat genotypes tested,seven allelic combinations of the three Vrn-1 genes were found to be responsible for the spring habit,three for the facultative habit and one for the winter habit.The three Vrn-1 genes behaved additively with the dominant allele of Vrn-A1 exerting the strongest effect.The allele combinations of the facultative genotypes and the discovery of spring genotypes with "winter" allele of Vrn-1 implied the presence of as yet unidentified alleles/genes for vernalization response.The dominant alleles of the three Vrn-1 genes were found in all ten ecological regions where wheat is cultivated in China,with Vrn-D1 as the most common allele in nine and Vrn-A1 in one.The combination of vrn-A1vrn-B1Vrn-D1 was the predominant genotype in seven of the regions.Compared with landraces,improved varieties contain a higher proportion of the spring type.This was attributed by a higher frequency of the dominant Vrn-A1 and Vrn-B1 alleles in the latter.Correlations between Vrn-1 allelic constitutions and heading date,spike length,plant type as well as cold tolerance were established.