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Direct visualization of single-molecule membrane protein interactions in living cells.

ABSTRACT: Interactions between membrane proteins are poorly understood despite their importance in cell signaling and drug development. Here, we present a co-immunoimmobilization assay (Co-II) enabling the direct observation of membrane protein interactions in single living cells that overcomes the limitations of currently prevalent proximity-based indirect methods. Using Co-II, we investigated the transient homodimerizations of epidermal growth factor receptor (EGFR) and beta-2 adrenergic receptor (?2-AR) in living cells, revealing the differential regulation of these receptors' dimerizations by molecular conformations and microenvironment in a plasma membrane. Co-II should provide a simple, rapid, and robust platform for visualizing both weak and strong protein interactions in the plasma membrane of living cells.

SUBMITTER: Kim DH

PROVIDER: S-EPMC6307816 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Direct visualization of single-molecule membrane protein interactions in living cells.

Kim Do-Hyeon DH Park Soyeon S Kim Dong-Kyun DK Jeong Min Gyu MG Noh Jungeun J Kwon Yonghoon Y Zhou Kai K Lee Nam Ki NK Ryu Sung Ho SH

PLoS biology 20181213 12

Interactions between membrane proteins are poorly understood despite their importance in cell signaling and drug development. Here, we present a co-immunoimmobilization assay (Co-II) enabling the direct observation of membrane protein interactions in single living cells that overcomes the limitations of currently prevalent proximity-based indirect methods. Using Co-II, we investigated the transient homodimerizations of epidermal growth factor receptor (EGFR) and beta-2 adrenergic receptor (β2-AR ...[more]

PMID: 30543635

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