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Liquid-liquid phase separation of the Golgi matrix protein GM130.

ABSTRACT: Golgins are an abundant class of peripheral membrane proteins of the Golgi. These very long (50-400 nm) rod-like proteins initially capture cognate transport vesicles, thus enabling subsequent SNARE-mediated membrane fusion. Here, we explore the hypothesis that in addition to serving as vesicle tethers, Golgins may also possess the capacity to phase separate and, thereby, contribute to the internal organization of the Golgi. GM130 is the most abundant Golgin at the cis Golgi. Remarkably, overexpressed GM130 forms liquid droplets in cells analogous to those described for numerous intrinsically disordered proteins with low complexity sequences, even though GM130 is neither low in complexity nor intrinsically disordered. Virtually pure recombinant GM130 also phase-separates into dynamic, liquid-like droplets in close to physiological buffers and at concentrations similar to its estimated local concentration at the cis Golgi.

SUBMITTER: Rebane AA

PROVIDER: S-EPMC7160038 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Liquid-liquid phase separation of the Golgi matrix protein GM130.

Rebane Aleksander A AA Ziltener Pascal P LaMonica Lauren C LC Bauer Antonia H AH Zheng Hong H López-Montero Iván I Pincet Frederic F Rothman James E JE Ernst Andreas M AM

FEBS letters 20191226 7

Golgins are an abundant class of peripheral membrane proteins of the Golgi. These very long (50-400 nm) rod-like proteins initially capture cognate transport vesicles, thus enabling subsequent SNARE-mediated membrane fusion. Here, we explore the hypothesis that in addition to serving as vesicle tethers, Golgins may also possess the capacity to phase separate and, thereby, contribute to the internal organization of the Golgi. GM130 is the most abundant Golgin at the cis Golgi. Remarkably, overexp ...[more]

PMID: 31833055

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