Dynamic early recruitment of GAK–Hsc70 regulates coated pit maturation
Abstract
Clathrin-mediated endocytosis (CME) begins with the assembly of clathrin onto the plasma membrane. These structures grow and stabilize to form clathrin-coated pits (CCPs), which invaginate and accumulate cargo. Finally, through membrane fission, CCPs detach to form clathrin-coated vesicles (CCVs). Mechanisms governing the transition of CCPs from flat-to-curved structures have been a matter of debate. GAK and its chaperone protein, Hsc70, are well known to mediate clathrin release from CCVs, and several studies have observed a late burst of GAK recruitment as CCVs form. Other studies have proposed that early recruitment of GAK–Hsc70 could function to provide the necessary energy source to remodel nascent flat clathrin lattices, replacing hexagons with pentagons and enabling a gain of curvature and invagination of the growing CCP; however, direct functional evidence is lacking. Here, we show that GAK knockdown inhibits CCP stabilization and invagination. Furthermore, mutations in the J domain of GAK that abolish Hsc70 recruitment to and activation at CCPs lead to the accumulation of GAK at CCPs, hinder CCP stabilization and invagination, and result in a striking increase in the proportion of highly transient, abortive CCPs. These findings support the hypothesis that GAK–Hsc70 promotes the turnover and remodeling of nascent clathrin assemblies required for curvature development during CME.
Article Details
Journal Info
Proceedings of the National Academy of Sciences
National Academy of Sciences
Authors (10)
Zhangping He
Department of Clinical Laboratory of The First Affiliated Hospital, National Health Commission Key Laboratory of Birth Defect Research and Prevention, Ministry of Education Key Laboratory of Rare Pediatric Diseases, Institute of Cytology and Genetics of School of Basic Medical Sciences, Hengyang Medical School, University of South China
Peiyao Zuo
Department of Clinical Laboratory of The First Affiliated Hospital, National Health Commission Key Laboratory of Birth Defect Research and Prevention, Ministry of Education Key Laboratory of Rare Pediatric Diseases, Institute of Cytology and Genetics of School of Basic Medical Sciences, Hengyang Medical School, University of South China
Peiliu Xu
Department of Clinical Laboratory of The First Affiliated Hospital, National Health Commission Key Laboratory of Birth Defect Research and Prevention, Ministry of Education Key Laboratory of Rare Pediatric Diseases, Institute of Cytology and Genetics of School of Basic Medical Sciences, Hengyang Medical School, University of South China
Haozhi Yuan
Department of Clinical Laboratory of The First Affiliated Hospital, National Health Commission Key Laboratory of Birth Defect Research and Prevention, Ministry of Education Key Laboratory of Rare Pediatric Diseases, Institute of Cytology and Genetics of School of Basic Medical Sciences, Hengyang Medical School, University of South China
Madhura Bhave
Department of Cell Biology, University of Texas Southwestern Medical Center
Xiangying Wei
Department of Oceanography, Fujian Key Laboratory on Conservation and Sustainable Utilization of Marine Biodiversity, Fuzhou Institute of Oceanography, College of Geography and Oceanography, Minjiang University
Ziyan Yang
Department of Clinical Laboratory of The First Affiliated Hospital, National Health Commission Key Laboratory of Birth Defect Research and Prevention, Ministry of Education Key Laboratory of Rare Pediatric Diseases, Institute of Cytology and Genetics of School of Basic Medical Sciences, Hengyang Medical School, University of South China
Lu Han
School of Chemical Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China
Sandra L. Schmid
Department of Cell Biology, University of Texas Southwestern Medical Center
Zhiming Chen
State Key Laboratory of Deep Earth Processes and Resources, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences