Regions of Human Chromosome 2 (2q32–q35) and Mouse Chromosome 1 Show Synteny with the Pufferfish Genome (Fugu rubripes)

We have isolated and sequenced a cosmid clone from the compact genome of the Japanese pufferfish (Fugu rubripes) containing portions of three genes that have the same order as in human. The gene order is microtubule-associated protein (MAP-2), myosin light chain (MYL-1), and carbamoyl phosphate synthetase (CPS III). The intron–exon organization ofFugu CPS IIIis identical with that of ratCPS I,although the equivalent genomic fragments of rat andFugu CPSspan 87.9 and 21 kb, respectively. This is the first report of a piscineCPS IIIgenomic structure and predicts a close evolutionary link betweenCPS IIIandCPS I.The 8-kb intergenic region betweenMYL-1andCPSgave no clear areas of transcription factor-binding sites by pairwise comparison with shark or ratCPSpromoter regions. However, there was a match with the rat myosin light chain 2 (MLC-2) gene promoter and a MyoD transcription factor-binding site 874 bp upstream of theMYL-1gene.