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SRC-mediated phosphorylation of dynamin and cortactin regulates the "constitutive" endocytosis of transferrin.

ABSTRACT: The mechanisms by which epithelial cells regulate clathrin-mediated endocytosis (CME) of transferrin are poorly defined and generally viewed as a constitutive process that occurs continuously without regulatory constraints. In this study, we demonstrate for the first time that endocytosis of the transferrin receptor is a regulated process that requires activated Src kinase and, subsequently, phosphorylation of two important components of the endocytic machinery, namely, the large GTPase dynamin 2 (Dyn2) and its associated actin-binding protein, cortactin (Cort). To our knowledge these findings are among the first to implicate an Src-mediated endocytic cascade in what was previously presumed to be a nonregulated internalization process.

SUBMITTER: Cao H

PROVIDER: S-EPMC2812239 | biostudies-literature | 2010 Feb

REPOSITORIES: biostudies-literature

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SRC-mediated phosphorylation of dynamin and cortactin regulates the "constitutive" endocytosis of transferrin.

Cao Hong H Chen Jing J Krueger Eugene W EW McNiven Mark A MA

Molecular and cellular biology 20091207 3

The mechanisms by which epithelial cells regulate clathrin-mediated endocytosis (CME) of transferrin are poorly defined and generally viewed as a constitutive process that occurs continuously without regulatory constraints. In this study, we demonstrate for the first time that endocytosis of the transferrin receptor is a regulated process that requires activated Src kinase and, subsequently, phosphorylation of two important components of the endocytic machinery, namely, the large GTPase dynamin ...[more]

PMID: 19995918

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