Selective Roles for Cholesterol and Actin in Compartmentalization of Different Proteins in the Golgi and Plasma Membrane of Polarized Cells Export

@article{citeulike:3426257, abstract = {To determine the roles of cholesterol and the actin cytoskeleton in apical and basolateral protein organization and sorting, we have performed comprehensive confocal fluorescence recovery after photobleaching analyses of apical and basolateral and raft- and non-raft-associated proteins, both at the plasma membrane and in the Golgi apparatus of polarized MDCK cells. We show that at both the apical and basolateral plasma membrane domains, raft-associated proteins diffuse faster than non-raft-associated proteins and that, different from the latter, they become restricted upon depletion of cholesterol. Furthermore, only transmembrane apical proteins are restricted by the actin network. This indicates that cholesterol-dependent domains exist both at the apical and basolateral membranes of polarized cells and that the actin cytoskeleton has a predominant role in the organization of transmembrane proteins independent of their association with rafts at the apical membrane. In the Golgi apparatus apical proteins appear to be segregated from the basolateral ones in a compartment that is sensitive both to cholesterol depletion and actin rearrangements. Furthermore, consistent with the role of actin rearrangements in apical protein sorting, we found that apical proteins exhibit a differential sensitivity to actin depolymerization in the Golgi of polarized and nonpolarized cells. 10.1074/jbc.M803819200}, author = {Lebreton, Stephanie and Paladino, Simona and Zurzolo, Chiara}, citeulike-article-id = {3426257}, citeulike-linkout-0 = {http://dx.doi.org/10.1074/jbc.M803819200}, citeulike-linkout-1 = {http://www.jbc.org/cgi/content/abstract/283/43/29545}, citeulike-linkout-2 = {http://view.ncbi.nlm.nih.gov/pubmed/18701450}, citeulike-linkout-3 = {http://www.hubmed.org/display.cgi?uids=18701450}, day = {24}, doi = {10.1074/jbc.M803819200}, journal = {J. Biol. Chem.}, keywords = {actin, cholesterol, compartment, golgi, lubret08pdf, membrane, plasma}, month = {October}, number = {43}, pages = {29545--29553}, posted-at = {2008-10-18 00:26:38}, priority = {2}, title = {Selective Roles for Cholesterol and Actin in Compartmentalization of Different Proteins in the Golgi and Plasma Membrane of Polarized Cells}, url = {http://dx.doi.org/10.1074/jbc.M803819200}, volume = {283}, year = {2008} }

TY - JOUR ID - citeulike:3426257 L3 - citeulike-article-id:3426257 N2 - To determine the roles of cholesterol and the actin cytoskeleton in apical and basolateral protein organization and sorting, we have performed comprehensive confocal fluorescence recovery after photobleaching analyses of apical and basolateral and raft- and non-raft-associated proteins, both at the plasma membrane and in the Golgi apparatus of polarized MDCK cells. We show that at both the apical and basolateral plasma membrane domains, raft-associated proteins diffuse faster than non-raft-associated proteins and that, different from the latter, they become restricted upon depletion of cholesterol. Furthermore, only transmembrane apical proteins are restricted by the actin network. This indicates that cholesterol-dependent domains exist both at the apical and basolateral membranes of polarized cells and that the actin cytoskeleton has a predominant role in the organization of transmembrane proteins independent of their association with rafts at the apical membrane. In the Golgi apparatus apical proteins appear to be segregated from the basolateral ones in a compartment that is sensitive both to cholesterol depletion and actin rearrangements. Furthermore, consistent with the role of actin rearrangements in apical protein sorting, we found that apical proteins exhibit a differential sensitivity to actin depolymerization in the Golgi of polarized and nonpolarized cells. 10.1074/jbc.M803819200 IS - 43 JF - J. Biol. Chem. EP - 29553 TI - Selective Roles for Cholesterol and Actin in Compartmentalization of Different Proteins in the Golgi and Plasma Membrane of Polarized Cells VL - 283 SP - 29545 KW - actin KW - cholesterol KW - compartment KW - golgi KW - lubret08pdf KW - membrane KW - plasma AU - Lebreton, Stephanie AU - Paladino, Simona AU - Zurzolo, Chiara PY - 2008/10/24/ UR - http://dx.doi.org/10.1074/jbc.M803819200 ER -