Regulation of cortical structure by the ezrin-radixin-moesin protein family.
Molecules involved in ERM (ezrin-radixin-moesin) based attachment of membrane proteins to the cortical cytoskeleton in cell surface structures have been identified. In lymphocytes, a direct interaction is seen with extracellular matrix receptors and intercellular adhesion molecules. In polarized epithelial cells, an adaptor molecule named EBP50 provides a bridge between the amino-terminal domain of ezrin and the cytoplasmic regions of plasma membrane proteins, including the cystic fibrosis transmembrane conductance regulator (CFTR) and the beta2 adrenergic receptor. ERM proteins are conformationally regulated - binding sites for EBP50 and F actin are masked in the dormant molecules and activation leads to exposure of these sites. The mechanism of activation, however, remains to be fully elucidated. ERM proteins also play a role in the Rho and Rac signaling pathways: activated ERM proteins can dissociate Rho-GDI (GDP dissociation inhibitor) from Rho and thereby activate Rho-dependent pathways.
Bretscher
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Section of Biochemistry, Molecular and Cell Biology Biotechnology Building Cornell University Ithaca NY 14853 USA. apb5@cornell.edu
D001798:Blood Proteins / Q000737:chemistry / Q000378:metabolism*; D002478:Cells, Cultured; D003598:Cytoskeletal Proteins; D003599:Cytoskeleton / Q000378:metabolism*; D006801:Humans; D008565:Membrane Proteins / Q000737:chemistry / Q000378:metabolism*; D008840:Microfilament Proteins / Q000737:chemistry / Q000378:metabolism*; D008954:Models, Biological; D010750:Phosphoproteins / Q000737:chemistry / Q000378:metabolism*; D011487:Protein Conformation; D015398:Signal Transduction; D000099149:Ezrin
D001798:Blood Proteins; D003598:Cytoskeletal Proteins; D008565:Membrane Proteins; D008840:Microfilament Proteins; D010750:Phosphoproteins; D000099149:Ezrin; C071058:moesin; C071776:radixin