Micro RNAs(mi RNAs)act as regulators of plant development and multiple stress responses.Here we demonstrate that the rice mi R171 b-SCL6-IIs module regulates the balance between blast resistance,grain yield,and flower...Micro RNAs(mi RNAs)act as regulators of plant development and multiple stress responses.Here we demonstrate that the rice mi R171 b-SCL6-IIs module regulates the balance between blast resistance,grain yield,and flowering.mi R171 b-overexpressing rice plants(OX171 b)displayed increased rice blast resistance accompanied with enhanced defense responses and late heading,whereas blocking mi R171 b expression in rice(MIM171)led to greater susceptibility to blast disease,associated with compromised defense responses and early heading.Either overexpressing or silencing of mi R171 b significantly affected plant height and number of filled seeds per panicle(seed-setting rate),resulting in decreased grain yield.mi R171 b targets SCL6-IIa,SCL6-IIb,and SCL6-IIc,whose expression was suppressed in OX171 b but increased in MIM171.Mutants of SCL6-IIa,SCL6-IIb,and SCL6-IIc all displayed phenotypes like that of OX171 b,including markedly increased blast disease resistance,slightly decreased grain yield,and delayed flowering.Amounts of mi R171 b increased gradually in leaves during the vegetative stage but decreased gradually in panicles during the reproductive stage,whereas SCL6-IIs displayed the reverse expression pattern.Together,these results suggest that the expression of mi R171 b was time-and space-dependent during the rice growth period and regulated the balance between rice blast disease resistance,grain yield,and flowering via SCL6-IIs,and that appropriate accumulation of mi R171 b is essential for rice development.展开更多
miR171 belongs to a highly conserved and ubiquitously expressed micro RNA gene family across species that play a critical role in controlling plant growth and development through the regulation of the miR171-SCL(scare...miR171 belongs to a highly conserved and ubiquitously expressed micro RNA gene family across species that play a critical role in controlling plant growth and development through the regulation of the miR171-SCL(scarecrow-like proteins)module.There is limited research available on the evolutionary relationship and functional diversification of miR171 members.In this study,we identified eight miR171 genes in the mulberry genome by bioinformatics analysis that were subsequently used to compare the evolutionary levels and explore abiotic stress mechanisms mediated by mno-miR171s(Morus notabilis miR171s).The results of phylogenetic analysis showed that the mature mno-miR171 sequences have strong sequence conservation,but their critical sites also exhibit high variation leading to functional diversification.Through quantitative real-time PCR,the expression profile of each mno-miR171 was analyzed under different stress treatments.All mno-miR171s,apart from mnomiR171h,were found to be significantly up-regulated under salt and drought stress conditions.The target genes of mno-miR171a namely,Morus020885 and Morus011800,were predicted and verified using the plural RNA method.5-rapid amplification of complementary DNA ends assays further to reveal that the target genes could be degraded by mno-miR171a post-transcriptionally.Overexpression of mno-miR171a in Arabidopsis improved the percentage of seed germination when the seeds were grown in NaCl-and mannitol-containing media.Transgenic plants were observed to grow better under drought conditions.The expression of various stress genes was significantly higher in transgenic plants than in wild type,except ERF11.Taken together,our study confirmed that mno-miR171a enhanced plant resistance to adverse stress environments via the regulation of the SCL targets.展开更多
基金supported by the National Natural Science Foundation of China(U19A2033,31672090,and 31430072)the Sichuan Applied Fundamental Research Foundation(2020YJ0332)to Wenming Wang。
文摘Micro RNAs(mi RNAs)act as regulators of plant development and multiple stress responses.Here we demonstrate that the rice mi R171 b-SCL6-IIs module regulates the balance between blast resistance,grain yield,and flowering.mi R171 b-overexpressing rice plants(OX171 b)displayed increased rice blast resistance accompanied with enhanced defense responses and late heading,whereas blocking mi R171 b expression in rice(MIM171)led to greater susceptibility to blast disease,associated with compromised defense responses and early heading.Either overexpressing or silencing of mi R171 b significantly affected plant height and number of filled seeds per panicle(seed-setting rate),resulting in decreased grain yield.mi R171 b targets SCL6-IIa,SCL6-IIb,and SCL6-IIc,whose expression was suppressed in OX171 b but increased in MIM171.Mutants of SCL6-IIa,SCL6-IIb,and SCL6-IIc all displayed phenotypes like that of OX171 b,including markedly increased blast disease resistance,slightly decreased grain yield,and delayed flowering.Amounts of mi R171 b increased gradually in leaves during the vegetative stage but decreased gradually in panicles during the reproductive stage,whereas SCL6-IIs displayed the reverse expression pattern.Together,these results suggest that the expression of mi R171 b was time-and space-dependent during the rice growth period and regulated the balance between rice blast disease resistance,grain yield,and flowering via SCL6-IIs,and that appropriate accumulation of mi R171 b is essential for rice development.
基金supported by the Natural Science Foundation of Hebei Province(Grant No.C2019406113)Hebei Provincial Department of Education(Grant No.QN2020236)Chengde Medical College Youth Foundation(Grant No.201913)。
文摘miR171 belongs to a highly conserved and ubiquitously expressed micro RNA gene family across species that play a critical role in controlling plant growth and development through the regulation of the miR171-SCL(scarecrow-like proteins)module.There is limited research available on the evolutionary relationship and functional diversification of miR171 members.In this study,we identified eight miR171 genes in the mulberry genome by bioinformatics analysis that were subsequently used to compare the evolutionary levels and explore abiotic stress mechanisms mediated by mno-miR171s(Morus notabilis miR171s).The results of phylogenetic analysis showed that the mature mno-miR171 sequences have strong sequence conservation,but their critical sites also exhibit high variation leading to functional diversification.Through quantitative real-time PCR,the expression profile of each mno-miR171 was analyzed under different stress treatments.All mno-miR171s,apart from mnomiR171h,were found to be significantly up-regulated under salt and drought stress conditions.The target genes of mno-miR171a namely,Morus020885 and Morus011800,were predicted and verified using the plural RNA method.5-rapid amplification of complementary DNA ends assays further to reveal that the target genes could be degraded by mno-miR171a post-transcriptionally.Overexpression of mno-miR171a in Arabidopsis improved the percentage of seed germination when the seeds were grown in NaCl-and mannitol-containing media.Transgenic plants were observed to grow better under drought conditions.The expression of various stress genes was significantly higher in transgenic plants than in wild type,except ERF11.Taken together,our study confirmed that mno-miR171a enhanced plant resistance to adverse stress environments via the regulation of the SCL targets.
