Neuropeptide hormone receptors: strategies for identification

Study of the structure--function relationship of neuropeptide hormone receptors presents a number of technical difficulties associated with the isolation of a given receptor protein in a purified form. A variety of molecular approaches has enabled corresponding cDNA clones to be isolated without the need to embark on protein purification procedures. However, the molecular cloning approach requires that appropriate tools for identifying cDNAs encoding the respective receptor be available. Strategies designed to address this problem will be discussed and include functional expression of neuropeptide hormone receptors in frog oocytes, hybrid depletion and inactivation of receptor-encoding mRNAs by RNase H digestion, polymerase chain reaction (PCR) amplification of cDNAs encoding putative receptors, and expression of transfected receptor genes in cell cultures followed by identification using a cell sorter.