Ya Zhang, Liyuan Han, Junjie Liu, Miao Chang, Chuanling Li, Jian-Xiu Shang, Zhiping Deng, Wenqiang Tang, Yu Sun
{"title":"在拟南芥中,两个e枝蛋白磷酸酶2c通过去磷酸化ABI1来增强ABA信号。","authors":"Ya Zhang, Liyuan Han, Junjie Liu, Miao Chang, Chuanling Li, Jian-Xiu Shang, Zhiping Deng, Wenqiang Tang, Yu Sun","doi":"10.1016/j.molp.2025.03.019","DOIUrl":null,"url":null,"abstract":"<p><p>ABA INSENSITIVE 1 (ABI1) and ABI2 are co-receptors of the phytohormone abscisic acid (ABA). Studies have demonstrated that phosphorylation of multiple amino acids on ABI1/2 augments their ability to inhibit ABA signaling in planta. However, whether and how the dephosphorylation of ABI1/2 is regulated to enhance plant sensitivity to ABA remain unknown. In this study, we identified two protein phosphatases, designated ABI1-Dephosphorylating E-clade PP2C 1 (ADEP1) and ADEP2, that interact with ABI1/2. Mutants lacking ADEP1, ADEP2, or both (adep1/2) exhibited reduced ABA inhibition of seed germination and root growth, as well as lower levels of ABA-induced stomatal closure. In addition, ABA-induced accumulation of ABI5 protein and expression of downstream target genes are reduced in the adep1/2 mutant compared with the wild type. These findings suggest that ADEP1/2 function as positive regulators of the ABA signaling pathway. Mass spectrometry analysis and two-dimensional electrophoresis identified Ser<sup>117</sup> as a major ABA-induced phosphorylation site on the ABI1 protein. ADEP1/2 can dephosphorylate Ser<sup>117</sup>, leading to destabilization of the ABI1 protein and increased sensitivity of plants to ABA. Moreover, ABA treatment decreases the abundance of ADEP1/2 proteins. In summary, our study reveals two novel regulatory proteins that modulate ABA signaling and provides new insights into the regulatory network that fine-tunes plant ABA responses.</p>","PeriodicalId":19012,"journal":{"name":"Molecular Plant","volume":" ","pages":"783-796"},"PeriodicalIF":17.1000,"publicationDate":"2025-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Two E-clade protein phosphatase 2Cs enhance ABA signaling by dephosphorylating ABI1 in Arabidopsis.\",\"authors\":\"Ya Zhang, Liyuan Han, Junjie Liu, Miao Chang, Chuanling Li, Jian-Xiu Shang, Zhiping Deng, Wenqiang Tang, Yu Sun\",\"doi\":\"10.1016/j.molp.2025.03.019\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>ABA INSENSITIVE 1 (ABI1) and ABI2 are co-receptors of the phytohormone abscisic acid (ABA). Studies have demonstrated that phosphorylation of multiple amino acids on ABI1/2 augments their ability to inhibit ABA signaling in planta. However, whether and how the dephosphorylation of ABI1/2 is regulated to enhance plant sensitivity to ABA remain unknown. In this study, we identified two protein phosphatases, designated ABI1-Dephosphorylating E-clade PP2C 1 (ADEP1) and ADEP2, that interact with ABI1/2. Mutants lacking ADEP1, ADEP2, or both (adep1/2) exhibited reduced ABA inhibition of seed germination and root growth, as well as lower levels of ABA-induced stomatal closure. In addition, ABA-induced accumulation of ABI5 protein and expression of downstream target genes are reduced in the adep1/2 mutant compared with the wild type. These findings suggest that ADEP1/2 function as positive regulators of the ABA signaling pathway. Mass spectrometry analysis and two-dimensional electrophoresis identified Ser<sup>117</sup> as a major ABA-induced phosphorylation site on the ABI1 protein. ADEP1/2 can dephosphorylate Ser<sup>117</sup>, leading to destabilization of the ABI1 protein and increased sensitivity of plants to ABA. Moreover, ABA treatment decreases the abundance of ADEP1/2 proteins. In summary, our study reveals two novel regulatory proteins that modulate ABA signaling and provides new insights into the regulatory network that fine-tunes plant ABA responses.</p>\",\"PeriodicalId\":19012,\"journal\":{\"name\":\"Molecular Plant\",\"volume\":\" \",\"pages\":\"783-796\"},\"PeriodicalIF\":17.1000,\"publicationDate\":\"2025-05-05\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Molecular Plant\",\"FirstCategoryId\":\"99\",\"ListUrlMain\":\"https://doi.org/10.1016/j.molp.2025.03.019\",\"RegionNum\":1,\"RegionCategory\":\"生物学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"2025/3/31 0:00:00\",\"PubModel\":\"Epub\",\"JCR\":\"Q1\",\"JCRName\":\"BIOCHEMISTRY & MOLECULAR BIOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Molecular Plant","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1016/j.molp.2025.03.019","RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2025/3/31 0:00:00","PubModel":"Epub","JCR":"Q1","JCRName":"BIOCHEMISTRY & MOLECULAR BIOLOGY","Score":null,"Total":0}
Two E-clade protein phosphatase 2Cs enhance ABA signaling by dephosphorylating ABI1 in Arabidopsis.
ABA INSENSITIVE 1 (ABI1) and ABI2 are co-receptors of the phytohormone abscisic acid (ABA). Studies have demonstrated that phosphorylation of multiple amino acids on ABI1/2 augments their ability to inhibit ABA signaling in planta. However, whether and how the dephosphorylation of ABI1/2 is regulated to enhance plant sensitivity to ABA remain unknown. In this study, we identified two protein phosphatases, designated ABI1-Dephosphorylating E-clade PP2C 1 (ADEP1) and ADEP2, that interact with ABI1/2. Mutants lacking ADEP1, ADEP2, or both (adep1/2) exhibited reduced ABA inhibition of seed germination and root growth, as well as lower levels of ABA-induced stomatal closure. In addition, ABA-induced accumulation of ABI5 protein and expression of downstream target genes are reduced in the adep1/2 mutant compared with the wild type. These findings suggest that ADEP1/2 function as positive regulators of the ABA signaling pathway. Mass spectrometry analysis and two-dimensional electrophoresis identified Ser117 as a major ABA-induced phosphorylation site on the ABI1 protein. ADEP1/2 can dephosphorylate Ser117, leading to destabilization of the ABI1 protein and increased sensitivity of plants to ABA. Moreover, ABA treatment decreases the abundance of ADEP1/2 proteins. In summary, our study reveals two novel regulatory proteins that modulate ABA signaling and provides new insights into the regulatory network that fine-tunes plant ABA responses.
期刊介绍:
Molecular Plant is dedicated to serving the plant science community by publishing novel and exciting findings with high significance in plant biology. The journal focuses broadly on cellular biology, physiology, biochemistry, molecular biology, genetics, development, plant-microbe interaction, genomics, bioinformatics, and molecular evolution.
Molecular Plant publishes original research articles, reviews, Correspondence, and Spotlights on the most important developments in plant biology.