A REGULATOR OF G-PROTEIN SIGNALING IN OLFACTORY RECEPTOR NEURONS

DEGENERATE primers were used in the polymerase chain reaction (PCR) to investigate the expression of encoding regulators of G-protein signal ing (RGS) in olfactory rosettes and in isolated olfactory receptor neu rons from channel catfish. Five cloned PCR products were obtained from olfactory rosettes that shared 78% amino acid sequence similarity to the mammalian RGS3 gene product. Southern blotting of PCR products fro m isolated olfactory receptor neurons showed that the catfish RGS3 hom olog was expressed in the neurons. These results suggest that the RGS3 gene may be involved in regulating G-protein signaling in olfactory r eceptor neurons. These results are also the first demonstration of RGS gene expression in a veterbrate sensory system.