Arginyltransferase 1 (ATE1)

ATE1 encodes an arginyltransferase, an enzyme that is involved in posttranslational conjugation of arginine to N-terminal aspartate or glutamate residues. Conjugation of arginine to the N-terminal aspartate or glutamate targets proteins for ubiquitin-dependent degradation. Alternative splicing results in two transcript variants encoding distinct isoforms. In mouse, both variants encode deduced 516-amino acid proteins with calculated molecular masses of about 59 kD. The 43-residue sequences encoded by the alternate exons are 31% identical. Northern blot analysis of mouse tissues revealed a 5-kb transcript in all tissues tested except testis, where the major transcript was 2 kb. Restriction digests of the transcripts suggested that the ratio of Ate1-1 to Ate1-2 varies between tissues.