Cancer/Testis Antigen Family 45, Member A4 (CT45A4)

By searching for genes upregulated in testis, followed by RT-PCR and genomic sequence analysis, Chen et al. (2005) identified 6 nearly identical copies of the CT45 gene, designated CT45A1 through CT45A6, on chromosome X. The CT45 genes appeared to be products of a recent gene duplication. RT-PCR and EST analysis revealed 3 CT45 transcript variants that differ in their 3-prime ends and represent the accumulated expression of the CT45 genes. All 3 transcripts encode a deduced 189-amino acid protein that shares significant similarity with DDX26B, SAGE, and DDX26. RT-PCR detected high CT45 expression in testis and variable expression in several cell lines. The 3 centromeric genes are transcribed in the centromeric-to-telomeric direction, and the 3 telomeric genes are transcribed in the opposite direction.