Genomic structure of murine Rab11 family members

Rab11a, Rab11b, and Rab25 in mammals are thought to comprise a subfamily of Rab proteins, although Rab25 has two amino acid differences in its effecto r domain. We have isolated and characterized the genomic sequences of murin e Rab11a and Rab25 and compared them with those of previously characterized mammalian Rab genes. The Rab11a gene spans 29 kb and Rab25 spans 9 kb. The genes have TATA-less promoters, but contain GC-rich areas in their upstrea m 5' regions. Both genes have 5 exons, with the introns containing characte ristic repeats. Rab11a has an unusually long 8.5-kb fourth intron. The Rab1 1a and Rab25 genes are localized to chromosomes 9C and 3E3/F1, respectively . The overall organization of the Rab11a, Rab11b, and Rab25 genes is simila r, with homologous exon-intron boundaries, and differs markedly from those of Rab3A and Rab1A. These results confirm that Rab11A, Rab11b, and Rab25 re present a closely related gene family. (C) 2000 Academic Press.