{"title":"Spliceosomal protein U2B″ delays leaf senescence by enhancing splicing variant JAZ9β expression to attenuate jasmonate signaling in Arabidopsis","authors":"Qi Yang, Shuya Tan, Hou-Ling Wang, Ting Wang, Jie Cao, Hairong Liu, Yueqi Sha, Yaning Zhao, Xinli Xia, Hongwei Guo, Zhonghai Li","doi":"10.1111/nph.19198","DOIUrl":null,"url":null,"abstract":"<div>\n \n <p>\n \n </p><ul>\n \n \n <li>\n \n <p>The regulatory framework of leaf senescence is gradually becoming clearer; however, the fine regulation of this process remains largely unknown.</p>\n </li>\n \n \n <li>\n \n <p>Here, genetic analysis revealed that U2 small nuclear ribonucleoprotein B (U2B″), a component of the spliceosome, is a negative regulator of leaf senescence. Mutation of U2B″ led to precocious leaf senescence, whereas overexpression of <i>U2B″</i> extended leaf longevity. Transcriptome analysis revealed that the jasmonic acid (JA) signaling pathway was activated in the <i>u2b″</i> mutant. U2B″ enhances the generation of splicing variant JASMONATE ZIM-DOMAIN 9β (JAZ9β) with an intron retention in the Jas motif, which compromises its interaction with CORONATINE INSENSITIVE1 and thus enhances the stability of JAZ9β protein. Moreover, JAZ9β could interact with MYC2 and obstruct its activity, thereby attenuating JA signaling. Correspondingly, overexpression of <i>JAZ9β</i> rescued the early senescence phenotype of the <i>u2b″</i> mutant.</p>\n </li>\n \n \n <li>\n \n <p>Furthermore, JA treatment promoted expression of U2B″ that was found to be a direct target of MYC2. Overexpression of <i>MYC2</i> in the <i>u2b″</i> mutant resulted in a more pronounced premature senescence than that in wild-type plants.</p>\n </li>\n \n \n <li>\n \n <p>Collectively, our findings reveal that the spliceosomal protein U2B″ fine-tunes leaf senescence by enhancing the expression of JAZ9β and thereby attenuating JA signaling.</p>\n </li>\n </ul>\n \n </div>","PeriodicalId":48887,"journal":{"name":"New Phytologist","volume":null,"pages":null},"PeriodicalIF":9.4000,"publicationDate":"2023-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"New Phytologist","FirstCategoryId":"99","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1111/nph.19198","RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"Agricultural and Biological Sciences","Score":null,"Total":0}
引用次数: 0
Abstract
The regulatory framework of leaf senescence is gradually becoming clearer; however, the fine regulation of this process remains largely unknown.
Here, genetic analysis revealed that U2 small nuclear ribonucleoprotein B (U2B″), a component of the spliceosome, is a negative regulator of leaf senescence. Mutation of U2B″ led to precocious leaf senescence, whereas overexpression of U2B″ extended leaf longevity. Transcriptome analysis revealed that the jasmonic acid (JA) signaling pathway was activated in the u2b″ mutant. U2B″ enhances the generation of splicing variant JASMONATE ZIM-DOMAIN 9β (JAZ9β) with an intron retention in the Jas motif, which compromises its interaction with CORONATINE INSENSITIVE1 and thus enhances the stability of JAZ9β protein. Moreover, JAZ9β could interact with MYC2 and obstruct its activity, thereby attenuating JA signaling. Correspondingly, overexpression of JAZ9β rescued the early senescence phenotype of the u2b″ mutant.
Furthermore, JA treatment promoted expression of U2B″ that was found to be a direct target of MYC2. Overexpression of MYC2 in the u2b″ mutant resulted in a more pronounced premature senescence than that in wild-type plants.
Collectively, our findings reveal that the spliceosomal protein U2B″ fine-tunes leaf senescence by enhancing the expression of JAZ9β and thereby attenuating JA signaling.
期刊介绍:
New Phytologist is a leading publication that showcases exceptional and groundbreaking research in plant science and its practical applications. With a focus on five distinct sections - Physiology & Development, Environment, Interaction, Evolution, and Transformative Plant Biotechnology - the journal covers a wide array of topics ranging from cellular processes to the impact of global environmental changes. We encourage the use of interdisciplinary approaches, and our content is structured to reflect this. Our journal acknowledges the diverse techniques employed in plant science, including molecular and cell biology, functional genomics, modeling, and system-based approaches, across various subfields.