| Title: | Receptor-independent activators of heterotrimeric G-proteins |
| Author(s): | Cismowski MJ; Takesono A; Bernard ML; Duzic E; Lanier SM; |
| Address: | "Department of Pharmacology, Medical University of South Carolina, Charleston 29425, USA" |
| DOI: | 10.1016/s0024-3205(01)01019-0 |
| ISSN/ISBN: | 0024-3205 (Print) 0024-3205 (Linking) |
| Abstract: | "Heterotrimeric G-protein signalling systems are primarily activated via cell surface receptors possessing the seven membrane span motif. Several observations suggest the existence of other modes of input to such signalling systems either downstream of effectors or at the level of G-proteins themselves. Using a functional screen based upon the pheromone response pathway in Saccharomyces cerevisiae, we identified three proteins, AGS1-3 (for Activators of G-protein Signalling), that activated heterotrimeric G-protein signalling pathways in the absence of a typical receptor. AGS1 defines a distinct member of the super family of ras related proteins. AGS2 is identical to mouse Tctex1, a protein that exists as a light chain component of the cytoplasmic motor protein dynein and subserves as yet undefined functions in cell signalling pathways. AGS3 possesses a series of tetratrico repeat motifs and a series of four amino acid repeats termed G-protein regulatory motifs. The GPR motifs are found in a number of proteins that interact with and regulate Galpha. Although each AGS protein activates G-protein signaling, they do so by different mechanisms within the context of the G-protein activation/deactivation cycle. AGS proteins provide unexpected mechanisms for input to heterotrimeric G-protein signalling pathways" |
| Keywords: | "Animals Chemoreceptor Cells/*metabolism GTP-Binding Proteins/genetics/metabolism Heterotrimeric GTP-Binding Proteins/*metabolism Humans Mice Molecular Sequence Data Receptors, Cell Surface/*metabolism Saccharomyces cerevisiae/genetics/metabolism *Signal T;" |
| Notes: | "MedlineCismowski, M J Takesono, A Bernard, M L Duzic, E Lanier, S M eng MH5993/MH/NIMH NIH HHS/ NS24821/NS/NINDS NIH HHS/ Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. Review Netherlands 2001/05/19 Life Sci. 2001 Apr 6; 68(19-20):2301-8. doi: 10.1016/s0024-3205(01)01019-0" |
