THE SEQUENCE OF THE MOUSE PHOSDUCIN-ENCODING GENE AND ITS 5'-FLANKINGREGION

Phosducin (Pd), a principal protein of retinal photoreceptor cells, mo dulates the phototransduction cascade by interacting with transducin. A recent report indicated that Pd and the G-protein-inhibitor protein (GIP) in brain are virtually identical. Here, we have sequenced the co mplete mouse clone (P1-AT) carrying the Pd gene, 3026 bp of its 5'-fla nking region, and cDNAs generated from the retinal mRNAs. Gene Pd is 1 5 kb in length and has four exons. The splice sites for donor and acce ptor were in good agreement with the GT/AG rule. Deduced Pd amino acid sequences were highly homologous to those of human, bovine and rat. I n addition, we found more than one similar Pd gene and two different m RNAs. The P1-AT clone encodes one of the Pd mRNAs. These results open the possibility that the multiple Pd genes encode multiple Pd.