In the chloroplasts/plastids and mitochondria of flowering plants,RNA editing alters hundreds of cytidines to uridines at specific sites mediated by the editosome.Over the past decade,Multiple Organellar RNA Editing F...In the chloroplasts/plastids and mitochondria of flowering plants,RNA editing alters hundreds of cytidines to uridines at specific sites mediated by the editosome.Over the past decade,Multiple Organellar RNA Editing Factor(MORF)proteins have emerged as essential regulators that affect the editing efficiency of most editing sites in plastids and mitochondria.In Arabidopsis,the MORF family consists of nine members,each possessing a single conserved MORF-box that is distributed among flowering plants.Accumulating studies have demonstrated that MORF proteins interact with many other factors,including the PPR proteins and enzymes in different biosynthetic pathways,indicating that the MORF proteins play a more extensive role in regulating organellar development than RNA editing.Recent studies reveal that MORF2 and MORF9 possess holdase activity and may act as chaperones and that MORF8 undergoes heatdependent phase separation to inhibit RNA editing in chloroplasts.In this review,we provide an overview of our current knowledge of the MORF family proteins and discuss the biological and molecular functions of this family in plants.展开更多
Plants continuously monitor environmental conditions （such as light and temperature） and adjust their growth and development accordingly. The transcription factor PHYTOCHROME-INTERACTING FACTOR4 （PIF4） regulates b...Plants continuously monitor environmental conditions （such as light and temperature） and adjust their growth and development accordingly. The transcription factor PHYTOCHROME-INTERACTING FACTOR4 （PIF4） regulates both light and temperature signaling pathways. Here, we identified ENHANCED PHOTOMORPHOGENIC2 （EPP2） as a new repressor of photomorphogenesis in red, far-red, and blue light. Map-based cloning revealed that EPP2 encodes the SEUSS （SEU） transcription regulator. The C terminus of SEU has transcriptional activation activity, and SEU physically interacts with PIF4. Moreover, SEU promotes the expression of many genes, including auxin biosynthetic and responsive genes, and regulates IAA levels in plants. SEU associates with the regulatory regions of INDOLE-3-ACETIC ACID INDUCIBLE6 （IAA6） and IAA 19 in a PIF4-independent manner, whereas the binding of PIF4to these genes requires SEU. Furthermore, muta- tions in SEU affect H3K4me3 methylation at IAA6 and IAA 19, and SEU positively regulates warm temperature- mediated hypocotyl growth together with PIF4. Collectively, our results reveal that SEU acts as a central regulator integrating light and temperature signals to control plant growth by coordinating with PIF4.展开更多
PHYTOCHROME-INTERACTING FACTORS(PIFs)are a group of basic helix-loop-helix transcription factors that can physically interact with photoreceptors,including phytochromes and cryptochromes.It was previously demonstrated...PHYTOCHROME-INTERACTING FACTORS(PIFs)are a group of basic helix-loop-helix transcription factors that can physically interact with photoreceptors,including phytochromes and cryptochromes.It was previously demonstrated that PIFs accumulated in darkness and repressed seedling photomorphogenesis,and that PIFs linked different photosensory and hormonal pathways to control plant growth and development.In this study,we show that PIFs positively regulate the ABA signaling pathway during the seedling stage specifically in darkness.We found that PIFs positively regulate ABI5 transcript and protein levels in darkness in response to exogenous ABA treatment by binding directly to the G-box motifs in the ABI5 promoter.Consistently,PIFs and the G-box motifs in the ABI5 promoter determine ABI5 expression in darkness,and overexpression of ABI5 could rescue the ABA-insensitive phenotypes of pifq mutants in the dark.Moreover,we discovered that PIFs can physically interact with the ABA receptors PYL8 and PYL9,and that this interaction is not regulated by ABA.Further analyses showed that PYL8 and PYL9 promote PIF4 protein accumulation in the dark and enhance PIF4 binding to the ABI5 promoter,but negatively regulate PIF4-mediated ABI5 activation.Taken together,our data demonstrate that PIFs interact with ABA receptors to orchestrate ABA signaling in darkness by controlling ABI5 expression,providing new insights into the pivotal roles of PIFs as signal integrators in regulating plant growth and development.展开更多
The phytochrome B (phyB) photoreceptor plays a major role that inputs light signals to regulate seed dormancy and germination. PHYTOCHROME-INTERACTING FACTOR1 (PIF1) is a key transcription factor repressing phyB-media...The phytochrome B (phyB) photoreceptor plays a major role that inputs light signals to regulate seed dormancy and germination. PHYTOCHROME-INTERACTING FACTOR1 (PIF1) is a key transcription factor repressing phyB-mediated seed germination, while REVEILLE1 (RVE1) factor functions as a curial regulator in controlling both seed dormancy and ger-mination. However, the relationship between the PIF1-and RVE1-modulated signaling pathways remains mostly unknown. Here, we find that PIF1 physically interacts with RVE1. Genetic analysis indicates that RVE1 inhibition on seed germination requires PIF1;re-ciprocally, the repressive effect of PIF1 is partially de-pendent on RVE1. Strikingly, PIF1 and RVE1 directly bind to the promoter and activate the expression of each other. Furthermore, PIF1 and RVE1 coordinately regulate the transcription of many downstream genes involved in abscisic acid and gibberellin pathways. Moreover, PIF1 enhances the DNA-binding ability and transcriptional repression activity of RVE1 in regulating GIBBERELLIN 3-OXIDASE2, and RVE1 promotes PIF1's DNA-binding ability in modulating ABSCISIC ACID-INSENSITIVE3 expression. Thus, this study demon-strates that PIF1 and RVE1 form a transcriptional feedback loop that coordinately inhibits seed germi-nation, providing a mechanistic understanding of how phyB-mediated light signal is transduced to the seeds.展开更多
Primary seed dormancy is acquired during seed development and maturation,which is important for plant fitness and survival.DELAY OF GERMINATION1(DOG1)plays a critical role in inducing seed dormancy.DOG1 expression inc...Primary seed dormancy is acquired during seed development and maturation,which is important for plant fitness and survival.DELAY OF GERMINATION1(DOG1)plays a critical role in inducing seed dormancy.DOG1 expression increases rapidly during seed development,but the precise mechanism underlying this process remains elusive.In this study,we showed that mutants with a loss or reduced function of the chromatin-remodeling factor PICKLE(PKL)exhibit increased seed dormancy.PKL associates with DOG1 chromatin and inhibits its transcription.We found that PKL physically interacts with LUX ARRHYTHMO(LUX),a member of the evening complex(EC)of the circadian clock.Furthermore,LUX directly binds to a specific coding sequence of DOG1,and DOG1 acts genetically downstream of PKL and LUX.Mutations in either LUX or EARLY FLOWERING3(ELF3)encoding another member of the EC led to increased DOG1 expression and enhanced seed dormancy.Surprisingly,these phenotypes were abolished when the parent plants were grown under continuous light.In addition,we observed that loss of function of either PKL or LUX decreased H3K27me3 levels at the DOG1 locus.Taken together,our study reveals a regulatory mechanism in which EC proteins coordinate with PKL to transmit circadian signals for directly regulating DOG1 expression and seed dormancy during seed development.展开更多
(Molecular Plant 11(7):928-942;July 2018;https://doi.Org/10.1016/j.molp.2018.04.005)In the Abstract of this article,there is an error in the sentence"SEU associates with the regulatory regions of INDOLE-3-ACETIC ...(Molecular Plant 11(7):928-942;July 2018;https://doi.Org/10.1016/j.molp.2018.04.005)In the Abstract of this article,there is an error in the sentence"SEU associates with the regulatory regions of INDOLE-3-ACETIC ACID INDUCIBLE6(IAA6)and IAA19 in a PIF4-independent manner,whereas the binding of PIF4 to these genes requires SEU.Furthermore.展开更多
基金supported by grants from the Key Research and Development Program of Zhejiang Province(2024SSYS0100)the National Natural Science Foundation of China(32030009)。
文摘In the chloroplasts/plastids and mitochondria of flowering plants,RNA editing alters hundreds of cytidines to uridines at specific sites mediated by the editosome.Over the past decade,Multiple Organellar RNA Editing Factor(MORF)proteins have emerged as essential regulators that affect the editing efficiency of most editing sites in plastids and mitochondria.In Arabidopsis,the MORF family consists of nine members,each possessing a single conserved MORF-box that is distributed among flowering plants.Accumulating studies have demonstrated that MORF proteins interact with many other factors,including the PPR proteins and enzymes in different biosynthetic pathways,indicating that the MORF proteins play a more extensive role in regulating organellar development than RNA editing.Recent studies reveal that MORF2 and MORF9 possess holdase activity and may act as chaperones and that MORF8 undergoes heatdependent phase separation to inhibit RNA editing in chloroplasts.In this review,we provide an overview of our current knowledge of the MORF family proteins and discuss the biological and molecular functions of this family in plants.
文摘Plants continuously monitor environmental conditions （such as light and temperature） and adjust their growth and development accordingly. The transcription factor PHYTOCHROME-INTERACTING FACTOR4 （PIF4） regulates both light and temperature signaling pathways. Here, we identified ENHANCED PHOTOMORPHOGENIC2 （EPP2） as a new repressor of photomorphogenesis in red, far-red, and blue light. Map-based cloning revealed that EPP2 encodes the SEUSS （SEU） transcription regulator. The C terminus of SEU has transcriptional activation activity, and SEU physically interacts with PIF4. Moreover, SEU promotes the expression of many genes, including auxin biosynthetic and responsive genes, and regulates IAA levels in plants. SEU associates with the regulatory regions of INDOLE-3-ACETIC ACID INDUCIBLE6 （IAA6） and IAA 19 in a PIF4-independent manner, whereas the binding of PIF4to these genes requires SEU. Furthermore, muta- tions in SEU affect H3K4me3 methylation at IAA6 and IAA 19, and SEU positively regulates warm temperature- mediated hypocotyl growth together with PIF4. Collectively, our results reveal that SEU acts as a central regulator integrating light and temperature signals to control plant growth by coordinating with PIF4.
基金supported by grants from the National Natural Science Foundation of China(31970262 and 31770321)the Ministry of Agriculture of China for Transgenic Research(2019ZX08010003-002-005)Beijing Outstanding University Discipline Program,and the Recruitm ent Program of Global Youth Experts of China.
文摘PHYTOCHROME-INTERACTING FACTORS(PIFs)are a group of basic helix-loop-helix transcription factors that can physically interact with photoreceptors,including phytochromes and cryptochromes.It was previously demonstrated that PIFs accumulated in darkness and repressed seedling photomorphogenesis,and that PIFs linked different photosensory and hormonal pathways to control plant growth and development.In this study,we show that PIFs positively regulate the ABA signaling pathway during the seedling stage specifically in darkness.We found that PIFs positively regulate ABI5 transcript and protein levels in darkness in response to exogenous ABA treatment by binding directly to the G-box motifs in the ABI5 promoter.Consistently,PIFs and the G-box motifs in the ABI5 promoter determine ABI5 expression in darkness,and overexpression of ABI5 could rescue the ABA-insensitive phenotypes of pifq mutants in the dark.Moreover,we discovered that PIFs can physically interact with the ABA receptors PYL8 and PYL9,and that this interaction is not regulated by ABA.Further analyses showed that PYL8 and PYL9 promote PIF4 protein accumulation in the dark and enhance PIF4 binding to the ABI5 promoter,but negatively regulate PIF4-mediated ABI5 activation.Taken together,our data demonstrate that PIFs interact with ABA receptors to orchestrate ABA signaling in darkness by controlling ABI5 expression,providing new insights into the pivotal roles of PIFs as signal integrators in regulating plant growth and development.
基金grants from the National Key Research and Development Program of China(2016YFD0100405)the Ministry of Agriculture of China(2016ZXo8009-003)the Postdoctoral Sci-ence Foundation of China(2018M641520).
文摘The phytochrome B (phyB) photoreceptor plays a major role that inputs light signals to regulate seed dormancy and germination. PHYTOCHROME-INTERACTING FACTOR1 (PIF1) is a key transcription factor repressing phyB-mediated seed germination, while REVEILLE1 (RVE1) factor functions as a curial regulator in controlling both seed dormancy and ger-mination. However, the relationship between the PIF1-and RVE1-modulated signaling pathways remains mostly unknown. Here, we find that PIF1 physically interacts with RVE1. Genetic analysis indicates that RVE1 inhibition on seed germination requires PIF1;re-ciprocally, the repressive effect of PIF1 is partially de-pendent on RVE1. Strikingly, PIF1 and RVE1 directly bind to the promoter and activate the expression of each other. Furthermore, PIF1 and RVE1 coordinately regulate the transcription of many downstream genes involved in abscisic acid and gibberellin pathways. Moreover, PIF1 enhances the DNA-binding ability and transcriptional repression activity of RVE1 in regulating GIBBERELLIN 3-OXIDASE2, and RVE1 promotes PIF1's DNA-binding ability in modulating ABSCISIC ACID-INSENSITIVE3 expression. Thus, this study demon-strates that PIF1 and RVE1 form a transcriptional feedback loop that coordinately inhibits seed germi-nation, providing a mechanistic understanding of how phyB-mediated light signal is transduced to the seeds.
基金This work was supported by grants from the National Key Research and Development Program of China(2016YFD0100405)the Ministry of Agriculture of China(2016ZX08009-003)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB27030205)the National Natural Science Foundation of China(31570310).
文摘Primary seed dormancy is acquired during seed development and maturation,which is important for plant fitness and survival.DELAY OF GERMINATION1(DOG1)plays a critical role in inducing seed dormancy.DOG1 expression increases rapidly during seed development,but the precise mechanism underlying this process remains elusive.In this study,we showed that mutants with a loss or reduced function of the chromatin-remodeling factor PICKLE(PKL)exhibit increased seed dormancy.PKL associates with DOG1 chromatin and inhibits its transcription.We found that PKL physically interacts with LUX ARRHYTHMO(LUX),a member of the evening complex(EC)of the circadian clock.Furthermore,LUX directly binds to a specific coding sequence of DOG1,and DOG1 acts genetically downstream of PKL and LUX.Mutations in either LUX or EARLY FLOWERING3(ELF3)encoding another member of the EC led to increased DOG1 expression and enhanced seed dormancy.Surprisingly,these phenotypes were abolished when the parent plants were grown under continuous light.In addition,we observed that loss of function of either PKL or LUX decreased H3K27me3 levels at the DOG1 locus.Taken together,our study reveals a regulatory mechanism in which EC proteins coordinate with PKL to transmit circadian signals for directly regulating DOG1 expression and seed dormancy during seed development.
文摘(Molecular Plant 11(7):928-942;July 2018;https://doi.Org/10.1016/j.molp.2018.04.005)In the Abstract of this article,there is an error in the sentence"SEU associates with the regulatory regions of INDOLE-3-ACETIC ACID INDUCIBLE6(IAA6)and IAA19 in a PIF4-independent manner,whereas the binding of PIF4 to these genes requires SEU.Furthermore.
