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Molecular architecture of the human caveolin-1 complex.

ABSTRACT: Membrane-sculpting proteins shape the morphology of cell membranes and facilitate remodeling in response to physiological and environmental cues. Complexes of the monotopic membrane protein caveolin function as essential curvature-generating components of caveolae, flask-shaped invaginations that sense and respond to plasma membrane tension. However, the structural basis for caveolin's membrane remodeling activity is currently unknown. Here, we show that, using cryo-electron microscopy, the human caveolin-1 complex is composed of 11 protomers organized into a tightly packed disc with a flat membrane-embedded surface. The structural insights suggest a previously unrecognized mechanism for how membrane-sculpting proteins interact with membranes and reveal how key regions of caveolin-1, including its scaffolding, oligomerization, and intramembrane domains, contribute to its function.

SUBMITTER: Porta JC

PROVIDER: S-EPMC9094659 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature

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Molecular architecture of the human caveolin-1 complex.

Porta Jason C JC Han Bing B Gulsevin Alican A Chung Jeong Min JM Peskova Yelena Y Connolly Sarah S Mchaourab Hassane S HS Meiler Jens J Karakas Erkan E Kenworthy Anne K AK Ohi Melanie D MD

Science advances 20220511 19

Membrane-sculpting proteins shape the morphology of cell membranes and facilitate remodeling in response to physiological and environmental cues. Complexes of the monotopic membrane protein caveolin function as essential curvature-generating components of caveolae, flask-shaped invaginations that sense and respond to plasma membrane tension. However, the structural basis for caveolin's membrane remodeling activity is currently unknown. Here, we show that, using cryo-electron microscopy, the huma ...[more]

PMID: 35544577

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