In this paper, the traditional empirical coefficient method and a novel loop material analytical method presented by the authors have been compared and discussed by analyzing several practical cylindrical workpieces’...In this paper, the traditional empirical coefficient method and a novel loop material analytical method presented by the authors have been compared and discussed by analyzing several practical cylindrical workpieces’ deep drawing projects. Also, some conclusions about how to modify the traditional analyzing method of cylindrical workpieces’ deep drawing process could be concluded and the necessity of this modification could be proved.展开更多
Tens of thousands of long non-coding RNAs have been uncovered in plants,but few of them have been comprehensively studied for their biological function and molecular mechanism of their mode of action.Here,we show that...Tens of thousands of long non-coding RNAs have been uncovered in plants,but few of them have been comprehensively studied for their biological function and molecular mechanism of their mode of action.Here,we show that the Arabidopsis long non-coding RNA DANA2 interacts with an AP2/ERF transcription factor ERF84 in the cell nucleus and then affects the transcription of JMJ29 that encodes a Jumonji C domain-containing histone H3K9 demethylase.Both RNA sequencing(RNA-seq)and genetic analyses demonstrate that DANA2 positively regulates drought stress responses through JMJ29.JMJ29 positively regulates the expression of ERF15 and GOLS2 by modulation of H3K9me2 demethylation.Accordingly,mutation of JMJ29 causes decreased ERF15 and GOLS2 expression,resulting in impaired drought tolerance,in agreement with drought-sensitive phenotypes of dana2 and erf84 mutants.Taken together,these results demonstrate that DANA2 is a positive regulator of drought response and works jointly with the transcriptional activator ERF84 to modulate JMJ29 expression in plant response to drought.展开更多
In plants,microRNA (miRNA) functions in the post-transcriptional repression of target mRNAs have been well explored.However,the mechanisms regulating the accumulation of miRNAs remain poorly under.stood.Here,we report...In plants,microRNA (miRNA) functions in the post-transcriptional repression of target mRNAs have been well explored.However,the mechanisms regulating the accumulation of miRNAs remain poorly under.stood.Here,we report that distinct mechanisms regulate accumulation of a monocot-specific miRNA,rice (Oryza sativa) miR528.At the transcriptional level,miR528 accumulated to higher levels in older plants than in young seedlings and exhibited aging-modulated gradual accumulation and diurnal rhythms in leaves;at the post-transcriptional level,aging also modulated miR528 levels by enhancing pri-miR528 alter.native splicing.We found that miR528 promotes rice flowering under long-day conditions by targeting RED AND FAR-RED INSENSITIVE2 (OsRFI2).Moreover,natural variations in the MIR528 promoter region caused differences in miR528 expression among rice varieties,which are correlated with their different binding affinities with the transcription factor OsSPL9 that activates the expression of miR528.Taken together,our findings reveal rice plants have evolved sophisticated modes fine-tuning miR528 levels and provide insight into the mechanisms that regulate MIRNA expression in plants.展开更多
Many microRNAs (miRNAs) are critical regulators of plant antiviral defense.However,little is known about how these miRNAs respond to virus invasion at the transcriptional level.We previously show that defense against ...Many microRNAs (miRNAs) are critical regulators of plant antiviral defense.However,little is known about how these miRNAs respond to virus invasion at the transcriptional level.We previously show that defense against Rice stripe virus (RSV) invasion entailed a reduction of miR528 accumulation in rice,alleviating miR528-mediated degradation of L-Ascorbate Oxidase (AO) mRNA and bolstering the antiviral activity of AO.Here we show that the miR528-A0 defense module is regulated by the transcription factor SPL9.SPL9 displayed high-affinity binding to specific motifs within the promoter region of miR528 and activated the expression of miR528 gene in vivo.Loss-of-function mutations in SPL9 caused a significant reduction in miR528 accumulation but a substantial increase of AO mRNA,resulting in enhanced plant resistance to RSV.Conversely,transgenic overexpression of SPL9 stimulated the expression of miR528 gene,hence lowering the level of AO mRNA and compromising rice defense against RSV.Importantly,gain in RSV susceptibility did not occur when SPL9 was overexpressed in mir528 loss-of-function mutants,or in transgenic rice expressing a miR528-resistant AO.Taken together,the finding of SPL9-mediated transcriptional activation of miR528 expression adds a new regulatory layer to the miR528-A0 antiviral defense pathway.展开更多
Dear Editor,Precise editing of specific genomic sites holds great promise in basic research and modern crop breeding,and some cytosine base editors(CBEs)have been developed for this purpose(Komor et al.,2016;Zong et a...Dear Editor,Precise editing of specific genomic sites holds great promise in basic research and modern crop breeding,and some cytosine base editors(CBEs)have been developed for this purpose(Komor et al.,2016;Zong et al.,2018).展开更多
文摘In this paper, the traditional empirical coefficient method and a novel loop material analytical method presented by the authors have been compared and discussed by analyzing several practical cylindrical workpieces’ deep drawing projects. Also, some conclusions about how to modify the traditional analyzing method of cylindrical workpieces’ deep drawing process could be concluded and the necessity of this modification could be proved.
基金supported by the National Natural Science Foundation of China(grants 32070627 and 31960138 to D.W.,31800224 and 32160070 to R.H.,and 31788103 to X.C.)the Chinese Academy of Sciences(Strategic Priority Research Program XDB27030201 to X.C.)the Natural Science Foundation of Jiangxi Province(grant 20171ACB20001 to D.W.).
文摘Tens of thousands of long non-coding RNAs have been uncovered in plants,but few of them have been comprehensively studied for their biological function and molecular mechanism of their mode of action.Here,we show that the Arabidopsis long non-coding RNA DANA2 interacts with an AP2/ERF transcription factor ERF84 in the cell nucleus and then affects the transcription of JMJ29 that encodes a Jumonji C domain-containing histone H3K9 demethylase.Both RNA sequencing(RNA-seq)and genetic analyses demonstrate that DANA2 positively regulates drought stress responses through JMJ29.JMJ29 positively regulates the expression of ERF15 and GOLS2 by modulation of H3K9me2 demethylation.Accordingly,mutation of JMJ29 causes decreased ERF15 and GOLS2 expression,resulting in impaired drought tolerance,in agreement with drought-sensitive phenotypes of dana2 and erf84 mutants.Taken together,these results demonstrate that DANA2 is a positive regulator of drought response and works jointly with the transcriptional activator ERF84 to modulate JMJ29 expression in plant response to drought.
基金supported by the National Natural Science Foundation of China (grants 91540203 and 31788103 to X.C.,31771872 to X.S.)The National Key Research and Development Program of China (2016YFD0100904)+3 种基金the Genetically Modified Breeding Major Projects (grant no.2016ZX08009001 -005 to X.S.)the Key Research Program of Frontier Sciences Chinese Academy of Sciences (QYZDY-SSWSMC022 to X.C.)Strategic Priority Research Program of Chinese Academy of Sciences (XDB27030201 to X.C.)the State Key Laboratory of Plant Genomics.
文摘In plants,microRNA (miRNA) functions in the post-transcriptional repression of target mRNAs have been well explored.However,the mechanisms regulating the accumulation of miRNAs remain poorly under.stood.Here,we report that distinct mechanisms regulate accumulation of a monocot-specific miRNA,rice (Oryza sativa) miR528.At the transcriptional level,miR528 accumulated to higher levels in older plants than in young seedlings and exhibited aging-modulated gradual accumulation and diurnal rhythms in leaves;at the post-transcriptional level,aging also modulated miR528 levels by enhancing pri-miR528 alter.native splicing.We found that miR528 promotes rice flowering under long-day conditions by targeting RED AND FAR-RED INSENSITIVE2 (OsRFI2).Moreover,natural variations in the MIR528 promoter region caused differences in miR528 expression among rice varieties,which are correlated with their different binding affinities with the transcription factor OsSPL9 that activates the expression of miR528.Taken together,our findings reveal rice plants have evolved sophisticated modes fine-tuning miR528 levels and provide insight into the mechanisms that regulate MIRNA expression in plants.
基金supported by grants from the Natural Science Foundation of China (31530062,31420103904 and 31722045)Transgenic Research Program (2016ZX08010-001,2016ZX08009003-001)Y.L.,and GARS- 01-06 to 乙H.X.,and Y.L.:ZY was supported by the National Postdoctoral Program for Innovative Talents (BX201700004).
文摘Many microRNAs (miRNAs) are critical regulators of plant antiviral defense.However,little is known about how these miRNAs respond to virus invasion at the transcriptional level.We previously show that defense against Rice stripe virus (RSV) invasion entailed a reduction of miR528 accumulation in rice,alleviating miR528-mediated degradation of L-Ascorbate Oxidase (AO) mRNA and bolstering the antiviral activity of AO.Here we show that the miR528-A0 defense module is regulated by the transcription factor SPL9.SPL9 displayed high-affinity binding to specific motifs within the promoter region of miR528 and activated the expression of miR528 gene in vivo.Loss-of-function mutations in SPL9 caused a significant reduction in miR528 accumulation but a substantial increase of AO mRNA,resulting in enhanced plant resistance to RSV.Conversely,transgenic overexpression of SPL9 stimulated the expression of miR528 gene,hence lowering the level of AO mRNA and compromising rice defense against RSV.Importantly,gain in RSV susceptibility did not occur when SPL9 was overexpressed in mir528 loss-of-function mutants,or in transgenic rice expressing a miR528-resistant AO.Taken together,the finding of SPL9-mediated transcriptional activation of miR528 expression adds a new regulatory layer to the miR528-A0 antiviral defense pathway.
基金supported by the National Natural Science Foundation of China(31960138)the Natural Science Foundation of Jiangxi Province(20171ACB20001)the National Key Research and Development Program of China(2016YRD0102003)。
文摘Dear Editor,Precise editing of specific genomic sites holds great promise in basic research and modern crop breeding,and some cytosine base editors(CBEs)have been developed for this purpose(Komor et al.,2016;Zong et al.,2018).
