Characterization of a putative SchistoFLRFamide receptor in the CNS of Locusta migratoria.
A putative SchistoFLRFamide receptor in CNS membrane preparations of Locusta migratoria was characterized by cold competition binding and kinetic binding assays using [125I][Y(1)]SchistoFLRFamide ([125I]YDVDHVFLRFamide) as a radioligand. Binding to this site was saturable, specific, reversible, and of high-affinity. Data fit to a single-site binding model by non-linear regression (r(2) = 0.99) estimated K(d) = 1.73 +/- 0.45 x 10(-9) M and B(max) = 49.0 +/- 12.2 fmol.mg(-1) tissue. Total binding of [125I][Y(1)]SchistoFLRFamide to membrane preparations was reduced in the presence of GTPgammaS, an indication that the putative receptor is G protein-coupled. Structure-activity studies determined that the minimum sequence required for binding was HVFLRFamide. Other aspects of the ligand receptor interaction were also examined.
Kwok
Rodney
R
Department of Zoology, University of Toronto, Ontario, M5S 3G5, Toronto, Canada. rdkwok@zoo.utoronto.ca
Orchard
Ian
I
D000818:Animals; D001665:Binding Sites; D002490:Central Nervous System / Q000378:metabolism; D006110:Grasshoppers / Q000378:metabolism*; D008024:Ligands; D009842:Oligopeptides / Q000737:chemistry / Q000378:metabolism; D011485:Protein Binding; D011869:Radioligand Assay; D018000:Receptors, Peptide / Q000378:metabolism*
D008024:Ligands; D009842:Oligopeptides; D018000:Receptors, Peptide; C095826:SchistoFLRFamide receptor; C066148:phenylalanyl-leucyl-arginyl phenylalaninamide