The phosphorylation of caveolin-2 on serines 23 and 36 modulates caveolin-1-dependent caveolae formation.
Caveolin-1 and -2 are the two major coat proteins found in plasma membrane caveolae of most of cell types. Here, by using adenoviral transduction of either caveolin-1 or caveolin-2 or both isoforms into cells lacking both caveolins, we demonstrate that caveolin-2 positively regulates caveolin-1-dependent caveolae formation. More importantly, we show that caveolin-2 is phosphorylated in vivo at two serine residues and that the phosphorylation of caveolin-2 is necessary for its actions as a positive regulator of caveolin-1 during organelle biogenesis in prostate cancer cells. Mutation of the primary phosphorylation sites on caveolin-2, serine 23 and 36, reduces the number of plasmalemma-attached caveolae and increases the accumulation of noncoated vesicles, but does not affect trafficking of caveolin-2, interaction with caveolin-1 or its biophysical properties. Thus, the phosphorylation of caveolin-2 is a novel mechanism to regulate the dynamics of caveolae assembly.
Department of Pharmacology, Vascular Cell Signaling and Therapeutics Program, Boyer Center for Molecular Medicine, Yale University School of Medicine, 295 Congress Avenue, New Haven, CT 06536, USA.
Grzegorz
G
Sowa
Marc
M
Pypaert
David
D
Fulton
William C
WC
Sessa
D000595:Amino Acid Sequence; D000818:Animals; D047390:Casein Kinase II; D051242:Caveolin 1; D051243:Caveolin 2; D022461:Caveolins / Q000737:chemistry / Q000378:metabolism*; D002460:Cell Line; D006801:Humans; D008969:Molecular Sequence Data; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D012694:Serine / Q000378:metabolism*
C495540:CAV1 protein, human; D051242:Caveolin 1; D051243:Caveolin 2; D022461:Caveolins; D012694:Serine; D047390:Casein Kinase II; D017346:Protein Serine-Threonine Kinases