Endomembrane-biased dimerization of ABCG16 and ABCG25 transporters determines their substrate selectivity in ABA-regulated plant growth and stress responses

作     者：Yeling Zhou Yuzhu Wang Dong Zhang Jiansheng Liang Yeling Zhou;Yuzhu Wang;Dong Zhang;Jiansheng Liang

作者机构：institute of Plant and Food ScienceDepartment of BiologySchool of Life SciencesSouthern University of Science and Technology(SUSTech)Shenzhen 518055China Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education InstitutesSouthern University of Science and Technology(SUSTech)Shenzhen 518055China jiangsu Key Laboratory of Crop Genetics and Physiology/Co-lnnovation Center for Modern Production Technology of Grain CropsKey Laboratory of Plant Functional Genomics of the Ministry of EducationYangzhou UniversityYangzhou 225009China 

出 版 物：《Molecular Plant》 (分子植物（英文版）)

年 卷 期：2024年第17卷第3期

页      面：478-495页

核心收录：

学科分类：0710[理学-生物学] 071001[理学-植物学] 07[理学] 

基　　金：supported by the National Natural Science Foundation of China(grant 32070292) the Shenzhen Science and Technology Program (grant KQTD20190929173906742) the Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes(grant 2019KSYS006) Shenzhen government for fundamental research(grant JCYJ20170817104523456) Scientific research funding for postdoctoral researchers staying at Shenzhen(grant K20227507) 

主　　题：abscisic acid ABCG transporter dimerization endomembrane substrate selectivity 

摘      要：ATP-binding cassette(ABC)transporters are integral membrane proteins that have evolved diverse func-tions fulfilled via the transport of various *** Arabidopsis,the G subfamily of ABC proteins is particularly abundant and participates in multiple signaling pathways during plant development and stress *** this study,we revealed that two Arabidopsis ABCG transporters,ABCG16 and ABCG25,engage in ABA-mediated stress responses and early plant growth through endomembrane-specific dimerization-coupled transport of ABA and ABA-glucosyl ester(ABA-GE),*** first revealed that ABCG16 contributes to osmotic stress tolerance via ABA *** specifically,ABCG16 induces cellular ABA efflux in both yeast and plant *** FRET analysis,we showed that ABCG16 forms oblig-atory homodimers for ABA export activity and that the plasma membrane-resident ABCG16 homodimers specifically respond to ABA,undergoing notable conformational ***,we demonstrated that ABCG16 heterodimerizes with ABCG25 at the endoplasmic reticulum(ER)membrane and facilitates the ER entry of ABA-GE in both Arabidopsis and tobacco *** specific responsiveness of the ABCG16-ABCG25 heterodimer to ABA-GE and the superior growth of their double mutant support an inhib-itory role of these twoABCGs in early seedling establishment via regulation of ABA-GE translocation across the ER *** endomembrane-specific analysis of the FRET signals derived from the homo-or heterodimerized ABcG complexes allowed us to link endomembrane-biased dimerization to the transloca-tion of distinct substrates by ABcG transporters,providing a prototypic framework for understanding the omnipotence of ABcG transporters in plant development and stress responses.