CLONING OF A RETINALLY ABUNDANT REGULATOR OF G-PROTEIN SIGNALING (RGS-R RGS16) - GENOMIC STRUCTURE AND CHROMOSOMAL LOCALIZATION OF THE HUMAN GENE/

Regulators of G-protein signaling (RGS) constitute a family of GTPase- activating proteins with varying tissue-specific expression patterns a nd G-protein alpha subunit specificities. Here, we describe the molecu lar cloning of the human RGS-r/RGS16 cDNA, encoding a predicted polype ptide of 23 kDa that shows 86% identity to mouse RGS-r. Northern blot analysis shows that, like the mouse Rgs-r message, hRGS-r mRNA is abun dantly expressed in retina, with lower levels of expression in most ot her tissues examined. Characterization of the genomic organization of the hRGS-r gene shows that it consists of five exons and four introns. We have also mapped the human RGS-r/RGS16 gene to chromosome 1q25-1q3 1 by fluorescence in situ hybridzation. Analysis of human ESTs reveals that at least five members of the RGS gene family map to chromosome 1 q, suggesting that at least part of the RGS family arose through gene duplication. The chromosomal location, retinal abundance, and presumed function of the human RGS-r protein in desensitizing photoreceptor si gnaling make the RGS-r/RGS16 locus a candidate for mutations responsib le for retinitis pigmentosa with para-arteriolar preservation of retin al pigment epithelium (RP-PPRE or RP12), an autosomal recessive disord er previously mapped to 1q31. (C) 1998 Elsevier Science B.V.