InterPro domain: IPR013048

Spo11 is a meiosis-specific protein that is responsible for the initiation of recombination during the early stages of meiosis through the formation of DNA double-strand breaks (DSBs) by a type II DNA topoisomerase-like activity [ 1 , 2 ]. These DSBs initiate homologous recombination, which is required for chromosomal segregation and generation of genetic diversity during meiosis. Spo11 acts in conjunction with several other proteins, including Rec102 in yeast, to bring about meiotic recombination [ 3 ]. Mouse and human homologues of Spo11 have been cloned and characterised. The proteins are 82% identical and share ~25% identity with other family members. Mouse Spo11 has been localised to chromosome 2H4, and human SPO11 to chromosome 20q13.2-q13.3, a region amplified in some breast and ovarian tumours [ 4 ].

Similarity between SPO11 and archaebacterial TOP6A proteins points to evolutionary specialisation of a DNA-cleavage function for meiotic recombination [ 4 ]. Note that the yeast SPO11 protein shares far less similarity to other SPO11 proteins than the human and mouse homologues do to each other.

1. Cloning, characterization, and localization of mouse and human SPO11. Genomics 61, 156-69
2. A DNA topoisomerase VI-like complex initiates meiotic recombination. Science 351, 939-43
3. Functional interactions between SPO11 and REC102 during initiation of meiotic recombination in Saccharomyces cerevisiae. Genetics 160, 111-22
4. Differential gene expression of mammalian SPO11/TOP6A homologs during meiosis. FEBS Lett. 462, 329-34