In eukaryotic cells,gene expression is greatly influenced by the dynamic chromatin environment.Epigenetic mechanisms,including covalent modifications to DNA and histone tails and the accessibility of chromatin,create ...In eukaryotic cells,gene expression is greatly influenced by the dynamic chromatin environment.Epigenetic mechanisms,including covalent modifications to DNA and histone tails and the accessibility of chromatin,create various chromatin states for stress-responsive gene expression that is important for adaptation to harsh environmental conditions.Recent studies have revealed that many epigenetic factors participate in abiotic stress responses,and various chromatin modifications are changed when plants are exposed to stressful environments.In this review,we summarize recent progress on the cross-talk between abiotic stress response pathways and epigenetic regulatory pathways in plants.Our review focuses on epigenetic regulation of plant responses to extreme temperatures,drought,salinity,the stress hormone abscisic acid,nutrient limitations and ultraviolet stress,and on epigenetic mechanisms of stress memory.展开更多
Abscisic acid(ABA)is a key regulator of plant responses to abiotic stresses,such as drought.Abscisic acid receptors and coreceptors perceive ABA to activate Snf1-related protein kinase2 s(SnRK2s)that phosphorylate dow...Abscisic acid(ABA)is a key regulator of plant responses to abiotic stresses,such as drought.Abscisic acid receptors and coreceptors perceive ABA to activate Snf1-related protein kinase2 s(SnRK2s)that phosphorylate downstream effectors,thereby activating ABA signaling and the stress response.As stress responses come with fitness penalties for plants,it is crucial to tightly control SnRK2 kinase activity to restrict ABA signaling.However,how SnRK2 kinases are inactivated remains elusive.Here,we show that NUCLEAR PORE ANCHOR(NUA),a nuclear pore complex(NPC)component,negatively regulates ABA-mediated inhibition of seed germination and post-germination growth,and drought tolerance in Arabidopsis thaliana.The role of NUA in response to ABA depends on SnRK2.2 and SnRK2.3 for seed germination and on SnRK2.6 for drought.NUA does not directly inhibit the phosphorylation of these SnRK2s or affects their abundance.However,the NUA-interacting protein EARLY IN SHORT DAYS 4(ESD4),a SUMO protease,negatively regulates ABA signaling by directly interacting with and inhibiting SnRK2 phosphorylation and protein levels.More importantly,we demonstrated that SnRK2.6 can be SUMOylated in vitro,and ESD4 inhibits its SUMOylation.Taken together,we identified NUA and ESD4 as SnRK2 kinase inhibitors that block SnRK2 activity,and reveal a mechanism whereby NUA and ESD4 negatively regulate plant responses to ABA and drought stress possibly through SUMOylation-dependent regulation of SnRK2s.展开更多
Circulating tumor cells(CTCs)are cancer cells that have propagated from primary tumor sites,spreading into the bloodstream as the cellular origin of fatal metastasis,and to secondary tumor sites.Capturing and analyzin...Circulating tumor cells(CTCs)are cancer cells that have propagated from primary tumor sites,spreading into the bloodstream as the cellular origin of fatal metastasis,and to secondary tumor sites.Capturing and analyzing CTCs is a kind of‘‘liquid biopsy'of the tumor that provides information about cancer changes over time and tailoring treatment[1].CTC enrichment and detection remains technologically challenging due to their extremely low concentra-展开更多
Heterochromatin is widespread in eukaryotic genomes and has diverse impacts depending on its genomic context.Previous studies have shown that a protein complex,the ASI1-AIPP1-EDM2(AAE)complex,participates in polyadeny...Heterochromatin is widespread in eukaryotic genomes and has diverse impacts depending on its genomic context.Previous studies have shown that a protein complex,the ASI1-AIPP1-EDM2(AAE)complex,participates in polyadenylation regulation of several intronic heterochromatin-containing genes.However,the genome-wide functions of AAE are still unknown.Here,we show that the ASI1 and EDM2 mostly target the common genomic regions on a genome-wide level and preferentially interacts with genetic heterochromatin.Polyadenylation(poly(A)sequencing reveals that AAE complex has a substantial influence on poly(A)site usage of heterochromatin-containing genes,includingnotonlyintronicheterochromatincontaining genes but also the genes showing overlap with heterochromatin.Intriguingly,AAE is also involved in the alternative splicing regulation of a number of heterochromatin-overlapping genes,such as the disease resistance gene RPP4.We provided evidence that genic heterochromatin is indispensable for the recruitment of AAE in polyadenylation and splicing regulation.In addition to conferring RNA processing regulation at genic heterochromatin-containing genes,AAE also targets some transposable elements(TEs)outside of genes(including TEs sandwiched by genes and island TEs)for epigenetic silencing.Our results reveal new functions of AAE in RNA processing and epigenetic silencing,and thus representimportantadvancesinepigenetic regulation.展开更多
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB27040203)the National Natural Science Foundation of China(31970157)。
文摘In eukaryotic cells,gene expression is greatly influenced by the dynamic chromatin environment.Epigenetic mechanisms,including covalent modifications to DNA and histone tails and the accessibility of chromatin,create various chromatin states for stress-responsive gene expression that is important for adaptation to harsh environmental conditions.Recent studies have revealed that many epigenetic factors participate in abiotic stress responses,and various chromatin modifications are changed when plants are exposed to stressful environments.In this review,we summarize recent progress on the cross-talk between abiotic stress response pathways and epigenetic regulatory pathways in plants.Our review focuses on epigenetic regulation of plant responses to extreme temperatures,drought,salinity,the stress hormone abscisic acid,nutrient limitations and ultraviolet stress,and on epigenetic mechanisms of stress memory.
基金supported by the Chinese Academy of Sciences,Chinasupported by the National Natural Science Foundation of China(31730066)the Huazhong Agricultural University’s Scientific and Technological SelfInnovation Foundation(2015RC014)。
文摘Abscisic acid(ABA)is a key regulator of plant responses to abiotic stresses,such as drought.Abscisic acid receptors and coreceptors perceive ABA to activate Snf1-related protein kinase2 s(SnRK2s)that phosphorylate downstream effectors,thereby activating ABA signaling and the stress response.As stress responses come with fitness penalties for plants,it is crucial to tightly control SnRK2 kinase activity to restrict ABA signaling.However,how SnRK2 kinases are inactivated remains elusive.Here,we show that NUCLEAR PORE ANCHOR(NUA),a nuclear pore complex(NPC)component,negatively regulates ABA-mediated inhibition of seed germination and post-germination growth,and drought tolerance in Arabidopsis thaliana.The role of NUA in response to ABA depends on SnRK2.2 and SnRK2.3 for seed germination and on SnRK2.6 for drought.NUA does not directly inhibit the phosphorylation of these SnRK2s or affects their abundance.However,the NUA-interacting protein EARLY IN SHORT DAYS 4(ESD4),a SUMO protease,negatively regulates ABA signaling by directly interacting with and inhibiting SnRK2 phosphorylation and protein levels.More importantly,we demonstrated that SnRK2.6 can be SUMOylated in vitro,and ESD4 inhibits its SUMOylation.Taken together,we identified NUA and ESD4 as SnRK2 kinase inhibitors that block SnRK2 activity,and reveal a mechanism whereby NUA and ESD4 negatively regulate plant responses to ABA and drought stress possibly through SUMOylation-dependent regulation of SnRK2s.
基金supported by the National Basic Research Program of China(2015CB932100,2013CB932703)the National Natural Science Foundation of China(11405185)
文摘Circulating tumor cells(CTCs)are cancer cells that have propagated from primary tumor sites,spreading into the bloodstream as the cellular origin of fatal metastasis,and to secondary tumor sites.Capturing and analyzing CTCs is a kind of‘‘liquid biopsy'of the tumor that provides information about cancer changes over time and tailoring treatment[1].CTC enrichment and detection remains technologically challenging due to their extremely low concentra-
基金supported by the Chinese Academy of Sciences,including the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB27040203 to C.-G.D.and XDB27040000 to J.K.Z)in part by a grant from the National Key Research and Development Project of China(2016YFE0108800 to Q.Q.L.)。
文摘Heterochromatin is widespread in eukaryotic genomes and has diverse impacts depending on its genomic context.Previous studies have shown that a protein complex,the ASI1-AIPP1-EDM2(AAE)complex,participates in polyadenylation regulation of several intronic heterochromatin-containing genes.However,the genome-wide functions of AAE are still unknown.Here,we show that the ASI1 and EDM2 mostly target the common genomic regions on a genome-wide level and preferentially interacts with genetic heterochromatin.Polyadenylation(poly(A)sequencing reveals that AAE complex has a substantial influence on poly(A)site usage of heterochromatin-containing genes,includingnotonlyintronicheterochromatincontaining genes but also the genes showing overlap with heterochromatin.Intriguingly,AAE is also involved in the alternative splicing regulation of a number of heterochromatin-overlapping genes,such as the disease resistance gene RPP4.We provided evidence that genic heterochromatin is indispensable for the recruitment of AAE in polyadenylation and splicing regulation.In addition to conferring RNA processing regulation at genic heterochromatin-containing genes,AAE also targets some transposable elements(TEs)outside of genes(including TEs sandwiched by genes and island TEs)for epigenetic silencing.Our results reveal new functions of AAE in RNA processing and epigenetic silencing,and thus representimportantadvancesinepigenetic regulation.
