Quantitative proteomics of caveolin-1-regulated proteins: characterization of polymerase i and transcript release factor/CAVIN-1 IN endothelial cells.
Caveolae are organelles abundant in the plasma membrane of many specialized cells including endothelial cells (ECs), epithelial cells, and adipocytes, and in these cells, caveolin-1 (Cav-1) is the major coat protein essential for the formation of caveolae. To identify proteins that require Cav-1 for stable incorporation into membrane raft domains, a quantitative proteomics analysis using isobaric tagging for relative and absolute quantification was performed on rafts isolated from wild-type and Cav-1-deficient mice. In three independent experiments, 117 proteins were consistently identified in membrane rafts with the largest differences in the levels of Cav-2 and in the caveola regulatory proteins Cavin-1 and Cavin-2. Because the lung is highly enriched in ECs, we validated and characterized the role of the newly described protein Cavin-1 in several cardiovascular tissues and in ECs. Cavin-1 was highly expressed in ECs lining blood vessels and in cultured ECs. Knockdown of Cavin-1 reduced the levels of Cav-1 and -2 and weakly influenced the formation of high molecular weight oligomers containing Cav-1 and -2. Cavin-1 silencing enhanced basal nitric oxide release from ECs but blocked proangiogenic phenotypes such as EC proliferation, migration, and morphogenesis in vitro. Thus, these data support an important role of Cavin-1 as a regulator of caveola function in ECs.
Dávalos
Alberto
A
Department of Pharmacology and Vascular Biology, Yale University School of Medicine, New Haven, Connecticut 06520, USA.
Fernández-Hernando
Carlos
C
Sowa
Grzegorz
G
Derakhshan
Behrad
B
Lin
Michelle I
MI
Lee
Ji Y
JY
Zhao
Hongyu
H
Luo
Ruiyan
R
Colangelo
Christopher
C
Sessa
William C
WC
D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western; D051242:Caveolin 1 / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D002465:Cell Movement; D049109:Cell Proliferation; D002852:Chromatography, Ion Exchange; D004256:DNA Polymerase I / Q000378:metabolism*; D020868:Gene Silencing; D006801:Humans; D013058:Mass Spectrometry; D051379:Mice; D018345:Mice, Knockout; D008856:Microscopy, Fluorescence; D009569:Nitric Oxide / Q000378:metabolism; D040901:Proteomics; D034741:RNA, Small Interfering
C495541:Cav1 protein, mouse; D051242:Caveolin 1; D034741:RNA, Small Interfering; D009569:Nitric Oxide; D004256:DNA Polymerase I