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Golgi vesicle proteins are linked to the assembly of an actin complex defined by mAbp1.

ABSTRACT: Recent studies indicate that regulation of the actin cytoskeleton is important for protein trafficking, but its precise role is unclear. We have characterized the ARF1-dependent assembly of actin on the Golgi apparatus. Actin recruitment involves Cdc42/Rac and requires the activation of the Arp2/3 complex. Although the actin-binding proteins mAbp1 (SH3p7) and drebrin share sequence homology, they are differentially segregated into two distinct ARF-dependent actin complexes. The binding of Cdc42 and mAbp1, which localize to the Golgi apparatus, but not drebrin, is blocked by occupation of the p23 cargo-protein-binding site on coatomer. Exogenously expressed mAbp1 is mislocalized and inhibits Golgi transport in whole cells. The ability of ARF, vesicle-coat proteins, and cargo to direct the assembly of cytoskeletal structures helps explain how only a handful of vesicle types can mediate the numerous trafficking steps in the cell.

SUBMITTER: Fucini RV

PROVIDER: S-EPMC65654 | biostudies-literature | 2002 Feb

REPOSITORIES: biostudies-literature

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Golgi vesicle proteins are linked to the assembly of an actin complex defined by mAbp1.

Fucini Raymond V RV Chen Ji-Long JL Sharma Catherine C Kessels Michael M MM Stamnes Mark M

Molecular biology of the cell 20020201 2

Recent studies indicate that regulation of the actin cytoskeleton is important for protein trafficking, but its precise role is unclear. We have characterized the ARF1-dependent assembly of actin on the Golgi apparatus. Actin recruitment involves Cdc42/Rac and requires the activation of the Arp2/3 complex. Although the actin-binding proteins mAbp1 (SH3p7) and drebrin share sequence homology, they are differentially segregated into two distinct ARF-dependent actin complexes. The binding of Cdc42 ...[more]

PMID: 11854417

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