Coordinated regulation of caveolin-1 and Rab11a in apical recycling compartments of polarized epithelial cells.
Recent studies have identified caveolin-1, a protein best known for its functions in caveolae, in apical endocytic recycling compartments in polarized epithelial cells. However, very little is known about the regulation of caveolin-1 in the endocytic recycling pathway. To address this question, in the current study we compared the relationship between compartments enriched in sub-apical caveolin-1 and Rab11a, a well-defined marker of apical recycling endosomes, using polarized MDCK cells as a model. We show that caveolin-1-containing vesicles define a compartment that partially overlaps with Rab11a, and that the distribution of subapical caveolin-1 and Rab11a shows a similar dependence on microtubule disruption. Mutants of the Rab11a effector, Rab11-FIP2 also altered the localization of caveolin-1. These findings indicate that caveolin-1 is coordinately regulated with Rab11a within the apical recycling system of polarized epithelial cells, suggesting that the two proteins are components of the same pathway.
Department of Surgery, Vanderbilt University School of Medicine, Nashville, TN 37232-0443, USA. lynne.lapierre@vanderbilt.edu
Lynne A
LA
Lapierre
Nicole A
NA
Ducharme
Kimberly R
KR
Drake
James R
JR
Goldenring
Anne K
AK
Kenworthy
D000818:Animals; D051242:Caveolin 1 / Q000378:metabolism*; D002460:Cell Line; D016764:Cell Polarity; D004285:Dogs; D004705:Endocytosis; D011992:Endosomes; D004847:Epithelial Cells / Q000378:metabolism; D008870:Microtubules / Q000378:metabolism; D020691:rab GTP-Binding Proteins / Q000378:metabolism*; D000099193:rab11 GTP-Binding Proteins
D051242:Caveolin 1; D020691:rab GTP-Binding Proteins; D000099193:rab11 GTP-Binding Proteins