Ubiquitin C (UBC)

Studies of ubiquitin cDNAs and genes show 2 unusual gene structural arrangements (Schlesinger and Bond, 1987). The first type of arrangement is the polyubiquitin gene, consisting of tandem repeats of a ubiquitin coding unit, with the number of repeats varying considerably even within species. Presumably posttranslational cleavage produces ubiquitin monomers from the primary translation product. The second structural type is the ubiquitin fusion gene, which encodes a single ubiquitin moiety fused to an unrelated tail protein. Three types of ubiquitin have been identified: A, B and C. The ubiquitin C (UBC) mRNA corresponds to a 9-coding-unit polyubiquitin gene.Board et al. (1992) determined that the UBC gene is located on chromosome 12. In situ hybridization with the same probe refined the assignment to 12q24.3.