首页|Endomembrane-biased dimerization of ABCG16 and ABCG25 transporters determines their substrate selectivity in ABA-regulated plant growth and stress responses
Endomembrane-biased dimerization of ABCG16 and ABCG25 transporters determines their substrate selectivity in ABA-regulated plant growth and stress responses
扫码查看
点击上方二维码区域，可以放大扫码查看
原文链接
万方数据
维普
ATP-binding cassette(ABC)transporters are integral membrane proteins that have evolved diverse func-tions fulfilled via the transport of various substrates.In Arabidopsis,the G subfamily of ABC proteins is particularly abundant and participates in multiple signaling pathways during plant development and stress responses.In 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),respectively.We first revealed that ABCG 16 contributes to osmotic stress tolerance via ABA signaling.More specifically,ABCG16 induces cellular ABA efflux in both yeast and plant cells.Using FRET analysis,we showed that ABCG 16 forms oblig-atory homodimers for ABA export activity and that the plasma membrane-resident ABCG16 homodimers specifically respond to ABA,undergoing notable conformational changes.Furthermore,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 cells.The 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 two ABCGs in early seedling establishment via regulation of ABA-GE translocation across the ER membrane.Our 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.
Institute of Plant and Food Science,Department of Biology,School of Life Sciences,Southern University of Science and Technology(SUSTech),Shenzhen 518055,China
Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education Institutes,Southern University of Science and Technology(SUSTech),Shenzhen 518055,China
Jiangsu Key Laboratory of Crop Genetics and Physiology/Co-Innovation Center for Modern Production Technology of Grain Crops,Key Laboratory of Plant Functional Genomics of the Ministry of Education,Yangzhou University,Yangzhou 225009,China
国家自然科学基金深圳市科技计划Key Laboratory of Molecular Design for Plant Cell Factory of Guangdong Higher Education InstitutesShenzhen government for fundamental researchScientific Research Funding for postdoctoral researchers staying at Shenzhen
万方数据
维普
