COMPLETE CDNA SEQUENCE, GENOMIC STRUCTURE, AND CHROMOSOMAL LOCALIZATION OF THE LPA RECEPTOR GENE, IPA(1) VZG-1/GPCR26/

The lp(A1)/Gpcr26 locus encodes the first cloned and identified G-prot ein-coupled receptor that specifically interacts with lysophosphatidic acid, A murine full-length cDNA of size consistent with that seen on Northern blots (3.7 kb) was determined using 3' rapid amplification of cDNA ends. Analysis of genomic clones revealed that the gene is divid ed into five exons, with one intron inserted in the coding region for transmembrane domain VI and one exon encoding the divergent 5' sequenc e in another published cDNA clone variant (orphan receptor mrec1.3). T his structure differs from the intronless coding region for a homologo us receptor, Edg1, but is identical to another more similar orphan rec eptor (lp(A2)) that has been deposited with GenBank. Using backcross a nalysis, both exons 1 and 4 mapped to a proximal region of murine Chro mosome 4 indistinguishable from the vacillans gene. Exon 4 also mapped to a second locus on proximal Chromosome 6 in Mus spretus, and this p artial duplication was confirmed by Southern blot. The genomic structu re indicates a distinct, divergent evolutionary lineage for the vzg-1/ lp(A1), subfamily of receptors compared to those of homologous orphan receptor genes. (C) 1998 Academic Press