From meiosis to postmeiotic events: homologous recombination is obligatory but flexible.
Sexual reproduction depends on the success of faithful chromosome transmission during meiosis to yield viable gametes. Central to meiosis is the process of recombination between paternal and maternal chromosomes, which boosts the genetic diversity of progeny and ensures normal homologous chromosome segregation. Imperfections in meiotic recombination are the source of de novo germline mutations, abnormal gametes, and infertility. Thus, not surprisingly, cells have developed a variety of mechanisms and tight controls to ensure sufficient and well-distributed recombination events within their genomes, the details of which remain to be fully elucidated. Local and genome-wide studies of normal and genetically engineered cells have uncovered a remarkable stochasticity in the number and positioning of recombination events per chromosome and per cell, which reveals an impressive level of flexibility. In this minireview, we summarize our contemporary understanding of meiotic recombination and its control mechanisms, and address the seemingly paradoxical and poorly understood diversity of recombination sites. Flexibility in the distribution of meiotic recombination events within genomes may reside in regulation at the chromatin level, with histone modifications playing a recently recognized role.
Székvölgyi
Lóránt
L
Recombination and Genome Instability Unit, Institut Curie, Centre de Recherche, UMR 3244 CNRS, Universite Pierre et Marie Curie, Paris, France.
Nicolas
Alain
A
D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics; D023902:Chromosome Pairing / Q000502:physiology; D020090:Chromosome Segregation; D003434:Crossing Over, Genetic / Q000502:physiology; D053903:DNA Breaks, Double-Stranded; D004250:DNA Topoisomerases, Type II / Q000502:physiology; D004706:Endodeoxyribonucleases; D006657:Histones / Q000378:metabolism; D006801:Humans; D007246:Infertility / Q000235:genetics; D008540:Meiosis / Q000502:physiology*; D051379:Mice; D011995:Recombination, Genetic / Q000502:physiology*; D012441:Saccharomyces cerevisiae / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000502:physiology; D012568:Schizosaccharomyces / Q000235:genetics; D012854:Sister Chromatid Exchange / Q000502:physiology; D000099257:Meiotic Recombination Protein SPO11
D004250:DNA Topoisomerases, Type II; D004706:Endodeoxyribonucleases; D006657:Histones; D029701:Saccharomyces cerevisiae Proteins; C518938:Spo11 protein, S cerevisiae; D000099257:Meiotic Recombination Protein SPO11