Modulation of meiotic homologous recombination by DNA helicases

Abstract

DNA helicases are ATP-driven motor proteins which translocate along DNA capable of dismantling DNA-DNA interactions and/or removing proteins bound to DNA. These biochemical capabilities make DNA helicases main regulators of crucial DNA metabolic processes, including DNA replication, DNA repair, and genetic recombination. This budding topic will focus on reviewing the function of DNA helicases important for homologous recombination during meiosis, and discuss recent advances in how these modulators of meiotic recombination are themselves regulated. The emphasis is placed on work in the two model yeasts, Saccharomyces cerevisiae and Schizosaccharomyces pombe, which has vastly expanded our understanding of meiotic homologous recombination, a process whose correct execution is instrumental for healthy gamete formation, and thus functioning sexual reproduction. Copyright © 2016 John Wiley & Sons, Ltd.

Defining the influence of Rad51 and Dmc1 lineage-specific amino acids on genetic recombination

“…Thus, we favor the hypothesis that mismatches may somehow alter the structure of the nucleoprotein complexes, thus rendering them more susceptible to disruption by regulatory enzymes. Several proteins are known to dissociate HR intermediates, including the S. cerevisiae helicases Srs2 and Sgs1 (BLM in humans), and the postreplicative mismatch repair machinery also plays a role in minimizing HR between divergent sequences (Spell and Jinks-Robertson 2004;Sugawara et al 2004;Spies and Fishel 2015;Branzei and Szakal 2017;Lorenz 2017). One possibility is that these or other enzymes may recognize some distinct mismatch-dependent structural feature that enables them to more readily act on Rad51-bound intermediates, whereas Dmc1 may shield mismatched intermediates from these enzymes (Fig.…”

Stress‐induced pyruvate accumulation contributes to cross protection in a fungus

“…The cosmopolitan fungus Metarhizium robertsii has versatile lifestyles; it is a pathogen of arthropods, a saprophyte and a colonizer of the rhizosphere and plant root (Roberts and St. Leger, 2004;Behie et al, 2012;2017;Guo et al, 2017). A multiyear field trial revealed that the ability of M. robertsii to maintain large populations is determined by its tolerance to abiotic stresses including temperature fluctuation and UV radiation (Fang and St. Leger, 2010;Wang et al, 2011).…”

Meiosis-specific recombinase Dmc1 is a potent inhibitor of the Srs2 antirecombinase

“…Srs2 is an ATP-dependent 3′→5′ ssDNA motor protein that plays a central role in minimizing cross-overs during mitosis (2, [10][11][12][13][14][15][16][17]. Srs2 functions by dismantling Rad51-ssDNA and D-loop intermediates, thereby channeling HR intermediates through the synthesis-dependent strand annealing (SDSA) pathway, which exclusively yields non-cross-over recombination products ( Fig.…”