Kubiak TM, Larsen MJ, Nulf SC, Zantello MR, Burton KJ, Bowman JW, Modric T, Lowery DE. Differential activation of "social" and "solitary" variants of the Caenorhabditis elegans G protein-coupled receptor NPR-1 by its cognate ligand AF9.
J Biol Chem 2003;
278:33724-9. [PMID:
12821653 DOI:
10.1074/jbc.m304861200]
[Citation(s) in RCA: 72] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Natural variations of wild Caenorhabditis elegans isolates having either Phe-215 or Val-215 in NPR-1, a putative orphan neuropeptide Y-like G protein-coupled receptor, result in either "social" or "solitary" feeding behaviors (de Bono, M., and Bargmann, C. I. (1998) Cell 94, 679-689). We identified a nematode peptide, GLGPRPLRF-NH2 (AF9), as a ligand activating the cloned NPR-1 receptor heterologously expressed in mammalian cells. Shifting cell culture temperatures from 37 to 28 degrees C, implemented 24 h after transfections, was essential for detectable functional expression of NPR-1. AF9 treatments linked both cloned receptor variants to activation of Gi/Go proteins and cAMP inhibition, thus allowing for classification of NPR-1 as an inhibitory G protein-coupled receptor. The Val-215 receptor isoform displayed higher binding and functional activity than its Phe-215 counterpart. This finding parallels the in vivo observation of a more potent repression of social feeding by the npr-1 gene encoding the Val-215 form of the receptor, resulting in dispersing (solitary) animals. Since neuropeptide Y shows no sequence homology to AF9 and was functionally inactive at the cloned NPR-1, we propose to rename NPR-1 and refer to it as an AF9 receptor, AF9-R1.
Collapse