Under warm temperatures,plants adjust their morphologies for environmental adaption via precise gene expression regulation.However,the function and regulation of alternative polyadenylation(APA),an important fine-tuni...Under warm temperatures,plants adjust their morphologies for environmental adaption via precise gene expression regulation.However,the function and regulation of alternative polyadenylation(APA),an important fine-tuning of gene expression,remains unknown in plant thermomorphogenesis.In this study,we found that SUMOylation,a critical post-translational modification,is induced by a long-term treat-ment at warm temperatures via a SUMO ligase SIZ1 in Arabidopsis.Disruption of SIZ1 altered the global usage of polyadenylation signals and affected the APA dynamic of thermomorphogenesis-related genes.CPSF100,a key subunit of the CPSF complex for polyadenylation regulation,is SUMOylated by SIZ1.Importantly,we demonstrated that SUMOylation is essential for the function of CPSF1oo in genome-wide polyadenylation site choice during thermomorphogenesis.Further analyses revealed that the SUMO conjugation on CPSF100 attenuates its interaction with two isoforms of its partner CPSF30,increasing the nuclear accumulation of CPsF1oo for polyadenylation regulation.In summary,our study uncovers a regulatory mechanism of APA via SiZ1-mediated SUMOylation in plant thermomorpho-genesis.展开更多
Plant immune responses are tightly regulated to ensure their appropriate deployment. Overexpression of TOPLESS-RELATED 1 (TPR1), a SUPPRESSOR OF npr1-1, CONSTITUTIVE 1 (SNC1)-interacting protein, results in autoimmuni...Plant immune responses are tightly regulated to ensure their appropriate deployment. Overexpression of TOPLESS-RELATED 1 (TPR1), a SUPPRESSOR OF npr1-1, CONSTITUTIVE 1 (SNC1)-interacting protein, results in autoimmunity that reduces plant growth and development. However, how TPR1 activity is regulated remains unknown. Loss of function of SIZ1, a (SUMO) E3 ligase, induces an autoimmune response, partially due to elevated SNC1 levels. Here we show that SNC1 expression is upregulated in Arabidopsis thaliana siz1-2 due to positive-feedback regulation by salicylic acid. SIZ1 physically interacts with TPR1 and facilitates its SUMO modification. The K282 and K721 residues in TPR1 serve as critical SUMO attachment sites. Simultaneous introduction of K282R and K721R substitutions in TPR1 blocked its SUMOylation, enhaneed its transcriptional co-repressor activity, and increased its association with HISTONE DEACETYLASE 19 (HDA19), suggesting that SUMOylation of TPR1 represses its transcriptional co-repressor activity and inhibits its interaction with HDA19. In agreement with this finding, the simultaneous introduction of K282R and K721R substitutions enhanced TPR1 mediated immunity, and the tpr1 mutation partially suppressed autoimmunity in siz1-2. These results demonstrate that SIZ1-mediated SUMOylation of TPR1 represses plant immunity, which at least partly contributes to the suppression of autoimmunity under nonpathogenic conditions to ensure proper plant development.展开更多
Sensitive to proton rhizotoxicity 1(STOP1) functions as a crucial regulator of root growth during aluminum(Al) stress. However, how this transcription factor is regulated by Al stress to affect downstream genes expres...Sensitive to proton rhizotoxicity 1(STOP1) functions as a crucial regulator of root growth during aluminum(Al) stress. However, how this transcription factor is regulated by Al stress to affect downstream genes expression is not well understood. To explore the underlying mechanisms of the function and regulation of STOP1, we employed a yeast two hybrid screen to identify STOP1-interacting proteins. The SUMO E3 ligase SIZ1, was found to interact with STOP1 and mainly facilitate its SUMO modification at K40 and K212 residues. Simultaneous introduction of K40 R and K212 R substitutions in STOP1 enhances its transactivation activity to upregulate the expression of aluminum-activated malate transporter 1(ALMT1)via increasing the association with mediator 16(MED16) transcriptional co-activator. Loss of function of SIZ1 causes highly increased expression of ALMT1, thus enhancing Al-induced malate exudation and Al tolerance. Also, we found that the protein level of SIZ1 is reduced in response to Al stress. Genetic evidence demonstrates that STOP1/ALMT1 is epistatic to SIZ1 in regulating root growth response to Al stress. This study suggests a mechanism about how the SIZ1–STOP1–ALMT1 signaling module is involved in root growth response to Al stress.展开更多
The 5-methylcytosine DNA glycosylase/lyase REPRESSOR OF SILENCING 1(ROS1)-mediated active DNA demethylation is critical for shaping the genomic DNA methylation landscape in Arabidopsis.Whether and how the stability of...The 5-methylcytosine DNA glycosylase/lyase REPRESSOR OF SILENCING 1(ROS1)-mediated active DNA demethylation is critical for shaping the genomic DNA methylation landscape in Arabidopsis.Whether and how the stability of ROS1 may be regulated by post-translational modifications is unknown.Using a methylation-sensitive PCR(CHOP-PCR)-based forward genetic screen forArabidopsis DNA hyper-methyl-ation mutants,we identified the SUMO E3 ligase SIZ1 as a critical regulator of active DNA demethylation.Dysfunction of SIZ1 leads to hyper-methylation at approximately 1000 genomic regions.SIZ1 physically in-teracts with ROS1 and mediates the SUMOylation of ROS1.The SUMOylation of ROS1 is reduced in siz1 mutant plants.Compared with that in wild-type plants,the protein level of ROS1 is significantly decreased,whereas there is an increased level of ROS1 transcripts in siz1 mutant plants.Our results suggest that SIZ1-mediated SUMOylation of ROS1 promotes its stability and positively regulates active DNA demethylation.展开更多
Arsenic is a metalloid toxic to plants,animals and human beings.Small ubiquitin-like modifier(SUMO)conjugation is involved in many biological processes in plants.However,the role of SUMOylation in regulating plant ars...Arsenic is a metalloid toxic to plants,animals and human beings.Small ubiquitin-like modifier(SUMO)conjugation is involved in many biological processes in plants.However,the role of SUMOylation in regulating plant arsenic response is still unclear.In this study,we found that dysfunction of SUMO E3 ligase SIZ1 improves arsenite resistance in Arabidopsis.Overexpression of the dominant-negative SUMO E2 variant resembled the arsenite-resistant phenotype of siz1 mutant,indicating that SUMOylation plays a negative role in plant arsenite detoxification.The siz1 mutant accumulated more glutathione(GSH)than the wild type under arsenite stress,and the arsenite-resistant phenotype of siz1 was depressed by inhibiting GSH biosynthesis.The transcript levels of the genes in the GSH biosynthetic pathway were increased in the siz1 mutant comparing with the wild type in response to arsenite treatment.Taken together,our findings revealed a novel function of SIZ1 in modulating plant arsenite response through regulating the GSH-dependent detoxification.展开更多
基金中央高校基本科研业务费专项(DL12CA10)东北林业大学科研训练项目(KY2015053)资助+1 种基金supported by the Fundamental Research Funds for the Central Universities(DL12CA10)the Research Training Program of Northeast Forestry University(KY2015053)
基金supported by grants from the Major Program of Guangdong Basic and Applied Research(2019B030302006)the National Natural Science Foundation of China(32000449,32270292,32270344,32270752,and 32170593)+3 种基金the China Postdoctoral Science Foundation(2020M672674)the Program for Changjang Scholars,the Natural Science Foundation of Guangdong Province,China(2024A1515011497,2020B1515020007,and 2024A1515011071)the Guangdong Provincial Pearl River Talent Plan(2019QN01N108)the National Science Foundation of USA(2347540).
文摘Under warm temperatures,plants adjust their morphologies for environmental adaption via precise gene expression regulation.However,the function and regulation of alternative polyadenylation(APA),an important fine-tuning of gene expression,remains unknown in plant thermomorphogenesis.In this study,we found that SUMOylation,a critical post-translational modification,is induced by a long-term treat-ment at warm temperatures via a SUMO ligase SIZ1 in Arabidopsis.Disruption of SIZ1 altered the global usage of polyadenylation signals and affected the APA dynamic of thermomorphogenesis-related genes.CPSF100,a key subunit of the CPSF complex for polyadenylation regulation,is SUMOylated by SIZ1.Importantly,we demonstrated that SUMOylation is essential for the function of CPSF1oo in genome-wide polyadenylation site choice during thermomorphogenesis.Further analyses revealed that the SUMO conjugation on CPSF100 attenuates its interaction with two isoforms of its partner CPSF30,increasing the nuclear accumulation of CPsF1oo for polyadenylation regulation.In summary,our study uncovers a regulatory mechanism of APA via SiZ1-mediated SUMOylation in plant thermomorpho-genesis.
基金the Chinese Academy of Sciences (XDA08010105)the National Natural Science Foundation of China (grant no. 31670186 and 31471363).
文摘Plant immune responses are tightly regulated to ensure their appropriate deployment. Overexpression of TOPLESS-RELATED 1 (TPR1), a SUPPRESSOR OF npr1-1, CONSTITUTIVE 1 (SNC1)-interacting protein, results in autoimmunity that reduces plant growth and development. However, how TPR1 activity is regulated remains unknown. Loss of function of SIZ1, a (SUMO) E3 ligase, induces an autoimmune response, partially due to elevated SNC1 levels. Here we show that SNC1 expression is upregulated in Arabidopsis thaliana siz1-2 due to positive-feedback regulation by salicylic acid. SIZ1 physically interacts with TPR1 and facilitates its SUMO modification. The K282 and K721 residues in TPR1 serve as critical SUMO attachment sites. Simultaneous introduction of K282R and K721R substitutions in TPR1 blocked its SUMOylation, enhaneed its transcriptional co-repressor activity, and increased its association with HISTONE DEACETYLASE 19 (HDA19), suggesting that SUMOylation of TPR1 represses its transcriptional co-repressor activity and inhibits its interaction with HDA19. In agreement with this finding, the simultaneous introduction of K282R and K721R substitutions enhanced TPR1 mediated immunity, and the tpr1 mutation partially suppressed autoimmunity in siz1-2. These results demonstrate that SIZ1-mediated SUMOylation of TPR1 represses plant immunity, which at least partly contributes to the suppression of autoimmunity under nonpathogenic conditions to ensure proper plant development.
基金supported by the National Natural Science Foundation of China(31470371 and 31770305)by Qingdao's Leading Technology Innovator Projectby Youth Interdisciplinary Science and Innovative Research Groups of Shandong University(2020QNQT014)。
文摘Sensitive to proton rhizotoxicity 1(STOP1) functions as a crucial regulator of root growth during aluminum(Al) stress. However, how this transcription factor is regulated by Al stress to affect downstream genes expression is not well understood. To explore the underlying mechanisms of the function and regulation of STOP1, we employed a yeast two hybrid screen to identify STOP1-interacting proteins. The SUMO E3 ligase SIZ1, was found to interact with STOP1 and mainly facilitate its SUMO modification at K40 and K212 residues. Simultaneous introduction of K40 R and K212 R substitutions in STOP1 enhances its transactivation activity to upregulate the expression of aluminum-activated malate transporter 1(ALMT1)via increasing the association with mediator 16(MED16) transcriptional co-activator. Loss of function of SIZ1 causes highly increased expression of ALMT1, thus enhancing Al-induced malate exudation and Al tolerance. Also, we found that the protein level of SIZ1 is reduced in response to Al stress. Genetic evidence demonstrates that STOP1/ALMT1 is epistatic to SIZ1 in regulating root growth response to Al stress. This study suggests a mechanism about how the SIZ1–STOP1–ALMT1 signaling module is involved in root growth response to Al stress.
文摘The 5-methylcytosine DNA glycosylase/lyase REPRESSOR OF SILENCING 1(ROS1)-mediated active DNA demethylation is critical for shaping the genomic DNA methylation landscape in Arabidopsis.Whether and how the stability of ROS1 may be regulated by post-translational modifications is unknown.Using a methylation-sensitive PCR(CHOP-PCR)-based forward genetic screen forArabidopsis DNA hyper-methyl-ation mutants,we identified the SUMO E3 ligase SIZ1 as a critical regulator of active DNA demethylation.Dysfunction of SIZ1 leads to hyper-methylation at approximately 1000 genomic regions.SIZ1 physically in-teracts with ROS1 and mediates the SUMOylation of ROS1.The SUMOylation of ROS1 is reduced in siz1 mutant plants.Compared with that in wild-type plants,the protein level of ROS1 is significantly decreased,whereas there is an increased level of ROS1 transcripts in siz1 mutant plants.Our results suggest that SIZ1-mediated SUMOylation of ROS1 promotes its stability and positively regulates active DNA demethylation.
基金supported by the National Natural Science Foundation of China(grant 32000206 to Z.W.)the Youth Innovation Promotion Association(2020273 to Z.W.)of the Chinese Academy of Sciences.
文摘Arsenic is a metalloid toxic to plants,animals and human beings.Small ubiquitin-like modifier(SUMO)conjugation is involved in many biological processes in plants.However,the role of SUMOylation in regulating plant arsenic response is still unclear.In this study,we found that dysfunction of SUMO E3 ligase SIZ1 improves arsenite resistance in Arabidopsis.Overexpression of the dominant-negative SUMO E2 variant resembled the arsenite-resistant phenotype of siz1 mutant,indicating that SUMOylation plays a negative role in plant arsenite detoxification.The siz1 mutant accumulated more glutathione(GSH)than the wild type under arsenite stress,and the arsenite-resistant phenotype of siz1 was depressed by inhibiting GSH biosynthesis.The transcript levels of the genes in the GSH biosynthetic pathway were increased in the siz1 mutant comparing with the wild type in response to arsenite treatment.Taken together,our findings revealed a novel function of SIZ1 in modulating plant arsenite response through regulating the GSH-dependent detoxification.
