Sequence homology of the 3'-untranslated region of calmodulin III in mammals.

Calmodulin (CaM) has three separate nonallelic genes that encode for three identical proteins. These genes differ considerably in the 5'- and 3'-untranslated regions (UTR) and in the promoter region. The sequence of the 3'-UTR of CaM III gene for rat and mouse was completed and compared to the human sequence. The rat and mouse 3'-UTR region had an identity of approximately 80% with the human. Three common polyadenylation signals in the 3'-UTR may account for the multiple CaM III transcripts. Although the untranslated regions are distinctively different for the three CaM genes, these regions are highly conserved among mammals. This high sequence conservation suggests an important function in the localization or regulation of CaM mRNA.