Arabidopsis protein S- acyl transferases positively mediate BR signaling through S- acylation of BSK1

• 成果类型: Article
• 署名作者: Liu, Fei; Qu, Peng-Yu; Li, Ji-Peng; Yang, Li-Na; Geng, Yuan-Jun; Lu, Jin-Yu; Zhang, Yan; Li, Sha
• 署名单位: Nankai University; Shandong Agricultural University
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-15201
• DOI: 10.1073/pnas.2322375121
• 发表日期: 2024-02-13
• 关键词: leaf senescence; receptor kinase; tip growth; palmitoylation; transduction; roles

摘要

Protein S-acyl transferases (PATs) catalyze S- acylation, a reversible post- translational modification critical for membrane association, trafficking, and stability of substrate proteins. Many plant proteins are potentially S- acylated but few have corresponding PATs identified. By using genomic editing, confocal imaging, pharmacological, genetic, and biochemical assays, we demonstrate that three Arabidopsis class C PATs positively regulate BR signaling through S- acylation of BRASSINOSTEROID- SIGNALING KINASE1 (BSK1). PAT19, PAT20, and PAT22 associate with the plasma membrane (PM) and the trans-Golgi network/early endosome (TGN/EE). Functional loss of all three genes results in a plethora of defects, indicative of reduced BR signaling and rescued by enhanced BR signaling. PAT19, PAT20, and PAT22 interact with BSK1 and are critical for the S- acylation of BSK1, and for BR signaling. The PM abundance of BSK1 was reduced by functional loss of PAT19 , PAT20 , and PAT22 whereas abolished by its S- acylation- deficient point mutations, suggesting a key role of S- acylation in its PM targeting. Finally, an active BR analog induces vacuolar trafficking and degradation of PAT19, PAT20, or PAT22, suggesting that the S- acylation of BSK1 by the three PATs serves as a negative feedback module in BR signaling. Significance Brassinosteriods (BRs) are plant hormones mediating various developmental processes. BSK1 relays BR signaling by interacting with the BR receptor BRI1 and phosphorylating downstream targets. Plasma membraneassociation of BSK1 relies on S- acylation, a reversible posttranslational modification catalyzed by protein S-acyl transferases (PATs). This study identifies Arabidopsis PAT19, PAT20, and PAT22 for BSK S- acylation, for BR signaling, and for plant development. In turn, BR signaling initiates vacuolar degradation of these PATs, providing a negative feedback module for BR- mediated growth.