Scherer P E, Okamoto T, Chun M, Nishimoto I, Lodish H F, Lisanti M P
Whitehead Institute for Biomedical Research, Cambridge, MA 02142-1479, USA.
Proc Natl Acad Sci U S A. 1996 Jan 9;93(1):131-5. doi: 10.1073/pnas.93.1.131.
Caveolin, a 21- to 24-kDa integral membrane protein, is a principal component of caveolae membranes. Caveolin interacts directly with heterotrimeric guanine nucleotide binding proteins (G proteins) and can functionally regulate their activity. Here, an approximately 20-kDa caveolin-related protein, caveolin-2, was identified through microsequencing of adipocyte-derived caveolin-enriched membranes; caveolin was retermed caveolin-1. Caveolins 1 and 2 are similar in most respects. mRNAs for both caveolin-1 and caveolin-2 are most abundantly expressed in white adipose tissue and are induced during adipocyte differentiation. Caveolin-2 colocalizes with caveolin-1, indicating that caveolin-2 also localizes to caveolae. However, caveolin-1 and caveolin-2 differ in their functional interactions with heterotrimeric G proteins, possibly explaining why caveolin-1 and -2 are coexpressed within a single cell.
小窝蛋白是一种21至24千道尔顿的整合膜蛋白，是小窝膜的主要成分。小窝蛋白直接与异三聚体鸟嘌呤核苷酸结合蛋白（G蛋白）相互作用，并能在功能上调节其活性。在此，通过对脂肪细胞来源的富含小窝蛋白的膜进行微量测序，鉴定出一种约20千道尔顿的小窝蛋白相关蛋白，即小窝蛋白-2；小窝蛋白被重新命名为小窝蛋白-1。小窝蛋白1和2在大多数方面相似。小窝蛋白-1和小窝蛋白-2的mRNA在白色脂肪组织中表达最为丰富，并在脂肪细胞分化过程中被诱导。小窝蛋白-2与小窝蛋白-1共定位，表明小窝蛋白-2也定位于小窝。然而，小窝蛋白-1和-2在与异三聚体G蛋白的功能相互作用上有所不同，这可能解释了为什么小窝蛋白-1和-2在单个细胞中共表达。
