Genomic Organization of the Leukotriene B4 Receptor Locus of Human Chromosome 14

Abstract

The genomic region containing the genes encoding the first leukotriene B4 receptor, BLTR, as well as the recently cloned second leukotriene B4-activated receptor, BLTR2, was mapped by (a) sequence analysis of a human bacterial artificial chromosome (BAC) library containing a 15-kb segment corresponding to chromosome 14q11.2-12 where the BLTR/BLTR2 genes were previously shown to be located, together with (b) sequence analysis of 83 expressed sequence tags (ESTs) from this region. The BLTR gene includes four different 5′ untranslated regions (UTRs) and a mutual acceptor site for the exon containing the intronless open reading frame. The BLTR2 gene is intronless and overlapped by a 5′ UTR splice version of BLTR and, on the reverse strand, of the apoptosis-related CIDE-B gene. This indicates a complex posttranscriptional gene regulation. Further adding to the complexity of the region is evidence of a fourth putative and novel gene, most homologous to the rat adenylyl cyclase IV gene.