Cloning and Characterization of a Putative G-Protein Coupled Receptor Potentially Involved in Development

Polymerase chain reaction techniques and medium stringency library screening were used to isolate a rat cDNA ("H218") which encodes a novel guanine nucleotide-binding protein coupled receptor homolog ("p H218"). Northern analysis revealed that brain H218 mRNA is preferentially expressed during embryogenesis. In addition, H218 mRNA is expressed in all developing tissues and rodent cell lines examined with highest levels detected in primitive, transformed cells. H218 mRNA expression in cell lines is rapidly increased by a tumor promoter and rapidly decreased by a differentiation-inducing growth factor. Finally, all of the sequence motifs characteristic of Src homology 2 domains are present in p H218 but in a unique arrangement. We conclude that p H218 may function as a growth factor receptor.