期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1999
卷号：96
期号：5
页码：1947-1952
DOI：10.1073/pnas.96.5.1947
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Proteins of the regulators of G protein signaling (RGS) family modulate the duration of intracellular signaling by stimulating the GTPase activity of G protein subunits. It has been established that the ninth member of the RGS family (RGS9) participates in accelerating the GTPase activity of the photoreceptor-specific G protein, transducin. This process is essential for timely inactivation of the phototransduction cascade during the recovery from a photoresponse. Here we report that functionally active RGS9 from vertebrate photoreceptors exists as a tight complex with the long splice variant of the G protein {beta} subunit (G{beta}5L). RGS9 and G{beta}5L also form a complex when coexpressed in cell culture. Our data are consistent with the recent observation that several RGS proteins, including RGS9, contain G protein {gamma}-subunit like domain that can mediate their association with G{beta}5 (Snow, B. E., Krumins, A. M., Brothers, G. M., Lee, S. F., Wall, M. A., Chung, S., Mangion, J., Arya, S., Gilman, A. G. & Siderovski, D. P. (1998) Proc. Natl. Acad. Sci. USA 95, 13307-13312). We report an example of such a complex whose cellular localization and function are clearly defined.
