Title: | Binding of fluorinated phenylalanine alpha-factor analogues to Ste2p: evidence for a cation-pi binding interaction between a peptide ligand and its cognate G protein-coupled receptor |
Author(s): | Tantry S; Ding FX; Dumont M; Becker JM; Naider F; |
Address: | "Department of Chemistry, College of Staten Island of the City University of New York, Staten Island, New York 10314, USA" |
ISSN/ISBN: | 1520-4995 (Electronic) 0006-2960 (Print) 0006-2960 (Linking) |
Abstract: | "Ste2p, a G protein-coupled receptor (GPCR), binds alpha-factor, WHWLQLKPGQPMY, a tridecapeptide pheromone secreted by yeast cells. Upon alpha-factor binding, Ste2p undergoes conformational changes activating a signal transduction system through its associated heterotrimeric G protein leading to the arrest of cell growth in the G1 phase to prepare cells for mating. Previous studies have indicated that Tyr at position 13 of alpha-factor interacts with Arg58 on transmembrane one (TM1) of Ste2p. This observation prompted this investigation to determine whether a cation-pi type of interaction occurred between these residues. Tyrosine at position 13 of alpha-factor was systematically substituted with analogous amino acids with varying cation-pi binding energies using solid-phase peptide synthesis, and these analogues were modified by derivatization of their Lys(7) residue with the fluorescent group 7-nitrobenz-2-oxa-1,3-diazole (NBD) to serve as a useful probe for binding determination. Saturation binding of these peptides to Ste2p was assayed using whole yeast cells and a flow cytometer. In parallel the biological activities of the peptides were determined using a growth arrest assay. The data provide evidence for the presence of a cation-pi interaction between Arg58 of Ste2p and Tyr(13) of alpha-factor" |
Keywords: | "Binding, Competitive Fluorine Mating Factor Peptides/chemistry/*metabolism/pharmacology Phenylalanine/*chemistry Pheromones/*metabolism Receptors, Mating Factor/drug effects/genetics/*metabolism Saccharomyces cerevisiae/genetics/metabolism Saccharomyces c;" |
Notes: | "MedlineTantry, Subramanyam Ding, Fa-Xiang Dumont, Mark Becker, Jeffrey M Naider, Fred eng R01 GM022087/GM/NIGMS NIH HHS/ R01 GM059357-08/GM/NIGMS NIH HHS/ GM059357/GM/NIGMS NIH HHS/ R01 GM059357/GM/NIGMS NIH HHS/ R01 GM022087-32/GM/NIGMS NIH HHS/ GM22087/GM/NIGMS NIH HHS/ R56 GM022087/GM/NIGMS NIH HHS/ Research Support, N.I.H., Extramural 2010/04/28 Biochemistry. 2010 Jun 22; 49(24):5007-15. doi: 10.1021/bi100280f" |