Role of RecQ helicases in DNA repair and gene targeting in moss (Plant Cell)

DNA repair is of course a crucial process, and many DNA repair enzymes are conserved across all domains of life. In humans, deficiency in the RecQ family of DNA helicase repair enzymes leads to premature aging and a predisposition to cancer. Previous studies have identified the RecQ family in Arabidopsis and rice. Wiedemann et al. characterize them in moss (Physcomitrella patens). Through knock-out and cross-species complementation studies they find different functions for two members of this family, PpRecQ4 and PpRecQ6. PpRecQ4 is involved in DNA repair and is a repressor of homologous DNA recombination, whereas PpRecQ6 is an enhancer of homologous DNA recombination. Interestingly, Arabidopsis seems to lack a homolog of RecQ6. This finding may help to explain why homologous DNA recombination (an important tool for gene characterization in moss) occurs so much more effectively in moss than Arabidopsis. (Summary by Mary Williams) Plant Cell 10.1105/tpc.17.00632