Characterisation of the human and mouse orthologues of the Drosophila ariadne gene

The specificity of the ubiquitin degradation system is regulated through in teraction between individual ubiquitin-conjugating enzymes (E2s) and multip le ubiquitin-protein ligases (E3s). Here we describe the characterisation o f a novel gene (ARIH1) that encodes the human homologue of Drosophila ariad ne which interacts with the E2s, UbcH7 and UbcH8 and represents a component of an E3 complex. Three PACs (189N19, 142P17 and 179H7) were isolated that contain this gene. Using these PACs as probes, we mapped ARIH1 to human ch romosome 15q24 by fluorescence in situ hybridisation (FISH). Sequencing of the ARIH1 PACs showed that the gene has 13 introns. In addition, we isolate d two PACs (345D8 and 571P19) containing the mouse orthologue (Arih1) of AR IH1. The intron-exon structure of Arih1 was identical to ARIH1 and the prot eins demonstrated a 98% identity at the amino acid level. Furthermore, comp arison of Drosophila ariadne with ARIH1 indicates an identity at the amino acid level of 70 % and introns at 3/7 identical sites. The high degree of h omology demonstrated by the mouse and human orthologues of Drosophila ariad ne indicates an important, conserved biological function, consistent with a putative role in ubiquitylation. Copyright (C) 2000 S. Karger AG, Basel.