The human homolog of a candidate mouse t complex responder gene: conserved motifs and evolution with punctuated...

The mouse Tcp-10 gene has been established as a molecular candidate for the t complex responder locus which plays a central role in the transmission ratio distortion phenotype expressed by males heterozygous for a t haplotype. Here we describe a comparison of the mouse and human TCP10 coding sequences. The results show that whole exons have been added or eliminated from the transcripts expressed in each species, suggesting an evolutionary process of punctuated equilibria for this gene. Two of the polypeptide regions that are most conserved between the two species contain specific peptide motifs. The conserved C-terminal region contains a unique nonapeptide repeat of unknown function and the conserved N-terminal region contains a pair of leucine zippers within a region that shows additional similarity to the coiled-coil regions of various cytosolic polypeptides. These results are discussed in terms of the possible function of the TCP10 protein.