Meiosis (R-HSA-1500620) [Homo sapiens]


During meiosis the replicated chromosomes of a single diploid cell are segregated into 4 haploid daughter cells by two successive divisions, meiosis I and meiosis II. In meiosis I, the distinguishing event of meiosis, pairs (bivalents) of homologous chromosomes in the form of sister chromatids are paired, synapsed along their regions of homologous DNA (reviewed in Yang and Wang 2009), and then segregated, resulting in haploid daughters containing sister chromatids paired at their centromeres (reviewed in Cohen et al. 2006, Handel and Schimenti 2010). The sister chromatids are then separated and segregated during meiosis II.
Recombination between chromosomal homologues but not between sister chromatids occurs during prophase of meiosis I (reviewed in Inagaki et al. 2010). Though hundreds of recombination events are initiated, most are resolved without crossovers and only tens proceed to become crossovers. In mammals recombination events are required between homologues for normal pairing, synapsis, and segregation.

Locations in the PathwayBrowser
Additional Information
Compartment nuclear envelope , nucleoplasm
Literature References
pubMedId Title Journal Year
20364103 DNA double strand break repair, chromosome synapsis and transcriptional silencing in meiosis Epigenetics 2010
16543383 Genetic analysis of chromosome pairing, recombination, and cell cycle control during first meiotic prophase in mammals Endocr Rev 2006
20051984 Genetics of mammalian meiosis: regulation, dynamics and impact on fertility Nat Rev Genet 2010
18948708 The Mammalian synaptonemal complex: a scaffold and beyond Genome Dyn 2009
Inferred Entries
Orthologous events