Cloning and characterization of the cDNA for the murine iduronate sulfatase gene.

Iduronate sulfatase (IDS; EC 3.1.6.13) is a lysosomal enzyme that acts on sulfate groups on C-2 positions of iduronic acid residues of the mucopolysaccharides dermatan and heparan sulfate. A deficiency of this enzyme activity in man leads to Hunter syndrome (Mucopolysaccharidosis type II). We report here the cloning and sequence characterization of the murine iduronate sulfatase cDNA which encodes 564 amino acid residues. Within the coding region the murine gene is 84.9 and 84.5 identical to the human gene at the nucleotide and amino acid levels, respectively. The two regions containing the putative catalytic site are especially well conserved. Genetic mapping of the murine Ids cDNA in an interspecific backcross confirms an X chromosomal location between Fmr-1 and Gabra3.