Genomic organization and chromosomal localization of the Asna1 gene, a mouse homologue of a bacterial arsenic-translocating ATPase gene

The plasmid encoded ArsA ATPase in Escherichia coli is the catalytic compon ent of an oxyanion pump that is responsible for resistance to arsenicals an d antimonials. Arsenite or antimonite allosterically activates the ArsA ATP ase activity. In this paper, we report the cloning and characterization of the mouse homologue (Asna1) of the bacterial arsA gene. The Asna1 gene enco des an open reading frame of 348 amino acids and exhibits 27% identity to t he bacterial ArsA protein and 99% similarity to its human counterpart (hASN A-1). The Asna1 mRNA is a similar to1.3 kb transcript and is present at hig h levels in kidney and testis, moderate levels in brain, liver, lung and sk in, and low levels in heart, small intestine, spleen, stomach, and thymus. A negligible amount of Asna1 transcript is detected in skeletal muscle. We have also characterized the genomic structure of the Asna1 gene. The gene s pans over 7 kb and consists of seven exons and six introns. All splice site s conform to the GT-AG rule, except for the splice donor site of intron 4 t hat is GC instead of GT. Fluorescence in situ hybridization indicates that the Asna1 gene is localized in the C3-D1 region of mouse chromosome 8. (C) 2001 Elsevier Science B.V. All rights reserved.