Endocytosis of BRASSINOSTEROID INSENSITIVE1 Is Partly Driven by a Canonical Tyr-Based Motif. Issue 11 (21st September 2020)

• Record Type: Journal Article
• Authors: Liu, Derui; Kumar, Rahul; Claus, Lucas A.N.; Johnson, Alexander J.; Siao, Wei; Vanhoutte, Isabelle; Wang, Peng; Bender, Kyle W.; Yperman, Klaas; Martins, Sara; Zhao, Xiuyang; Vert, Grégory; Van Damme, Daniël; Friml, Jiří; Russinova, Eugenia
• Is Part Of: The Plant Cell. Volume 32:Issue 11(2020)
• Page Start: 3598
• Page End: 3612
• Publication Date: 2020-09-21
• DOI: 10.1105/tpc.20.00384
• Languages: English
• ISSNs: 1040-4651

Abstract

Abstract : Canonical Tyr endocytic motifs are functional in plants and control the internalization of plasma membrane proteins by the clathrin adaptor complex AP-2. Abstract: Clathrin-mediated endocytosis (CME) and its core endocytic machinery are evolutionarily conserved across all eukaryotes. In mammals, the heterotetrameric adaptor protein complex-2 (AP-2) sorts plasma membrane (PM) cargoes into vesicles via the recognition of motifs based on Tyr or di-Leu in their cytoplasmic tails. However, in plants, very little is known about how PM proteins are sorted for CME and whether similar motifs are required. In Arabidopsis ( Arabidopsis thaliana ), the brassinosteroid (BR) receptor BR INSENSITIVE1 (BRI1) undergoes endocytosis, which depends on clathrin and AP-2. Here, we demonstrate that BRI1 binds directly to the medium AP-2 subunit (AP2M). The cytoplasmic domain of BRI1 contains five putative canonical surface-exposed Tyr-based endocytic motifs. The Tyr-to-Phe substitution in Y898 KAI reduced BRI1 internalization without affecting its kinase activity. Consistently, plants carrying the BRI1 Y898F mutation were hypersensitive to BRs. Our study demonstrates that AP-2–dependent internalization of PM proteins via the recognition of functional Tyr motifs also operates in plants.