Functional screening of multiuse peptide libraries using melanophore bioassay.

Abstract

This chapter describes the apphcation of recombinant melanophores to study cellular responses artsing from individual beads of a multmse peptide library (MUPL). In the melanophores, a cell hne derived from Xenopus Zuevis skin, pigment dispersion can be effected via actrvation of adenyl cyclase (,) or phospholipase C (), while pigment aggregation results from inhibition of adenyl cyclase (,). It has been shown that melanophore cells contain a wide range of Gα-proteins () that facilitate the coupling of numerous foreign G-protein coupled receptors (GPCRs) in melanophores ( Fig. 1 ). Smce both states of intracellular pigment dtstrtbution (dispersion or aggregation) are easily detectable, numerous recombinant GPCRs, such as the bombesm receptor (), can be studied by monitoring ligand-mediated melanosome translocation (). The pigment translocation assay is an attractive tool for functional screening of MUPLs due to the ability of melanophores to functionally express numerous exogenous GPCRs. Therefore the recombinant melanophores allow MUPLs to be screened for the presence of new agonists or antagomsts and for elucidating principles govermng molecular mteractions It is expected that apphcations of MUPLs in conjunction with functional assays will enhance both basic scientific research and the rates of drug discovery and development Open image in new window Fig. 1. In the melanophores, pigment dispersion can be effected via activation of adenyl cyclase or phospholipase C, while pigment aggregation results from inhibition of adenyl cyclase.