SPO11 Meiotic Protein Covalently Bound To DSB Homolog (SPO11)

SPO11 is similar in sequence and conserved features to the yeast meiotic recombination protein. The encoded protein belongs to the TOP6A protein family. Several transcript variants encoding different isoforms have been found for this gene, but the full-length nature of only two of them have been described. The human and the mouse SPO11 proteins share 82% amino acid identity, but only 20 to 30% with other eukaryotic homologs such as Drosophila and C. elegans. Both the mouse and human SPO11 exons 2 and 8 are subject to alternative splicing. Northern blot analysis showed that mouse Spo11 is expressed in testis and thymus as a 1.8-kb mRNA, whereas human SPO11 is expressed in testis as a 2.0-kb transcript. RT-PCR revealed that human SPO11 is also expressed in prostate, fetal testis, thymus, and some carcinoma cell lines.