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Exo70 subunit of the exocyst complex is involved in adhesion-dependent trafficking of caveolin-1.

ABSTRACT: Caveolae are specialized domains of the plasma membrane, which play key roles in signaling, endocytosis and mechanosensing. Using total internal reflection fluorescent microscopy (TIRF-M), we observe that the exocyst subunit Exo70 forms punctuate structures at the plasma membrane and partially localizes with caveolin-1, the main component of caveolae. Upon cell detachment, we found that Exo70 accumulates with caveolin-1-positive vesicular structures. Upon cell re-adhesion, caveolin-1 traffics back to the plasma membrane in a multistep process involving microtubules and actin cytoskeleton. In addition, silencing of Exo70 redirects caveolin-1 to focal adhesions identified by markers such as ?5 integrin or vinculin. Based on these findings, we conclude that Exo70 is involved in caveolin-1 recycling to the plasma membrane during re-adhesion of the cells to the substratum.

SUBMITTER: Hertzog M

PROVIDER: S-EPMC3531403 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Exo70 subunit of the exocyst complex is involved in adhesion-dependent trafficking of caveolin-1.

Hertzog Maud M Monteiro Pedro P Le Dez Gaëlle G Chavrier Philippe P

PloS one 20121227 12

Caveolae are specialized domains of the plasma membrane, which play key roles in signaling, endocytosis and mechanosensing. Using total internal reflection fluorescent microscopy (TIRF-M), we observe that the exocyst subunit Exo70 forms punctuate structures at the plasma membrane and partially localizes with caveolin-1, the main component of caveolae. Upon cell detachment, we found that Exo70 accumulates with caveolin-1-positive vesicular structures. Upon cell re-adhesion, caveolin-1 traffics ba ...[more]

PMID: 23300727

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