The Drosophila meiotic kleisin C(2)M functions before the meiotic divisions
- First Online:
- 252 Downloads
Stepwise and regionally controlled resolution of sister chromatid cohesion is thought to be crucial for faithful chromosome segregation during meiotic divisions. In yeast, the meiosis-specific α-kleisin subunit of the cohesin complex, Rec8, is protected from cleavage by separase but only during meiosis I and specifically within the pericentromeric region. While the Drosophila genome does not contain an obvious Rec8 orthologue, as other animal and plant genomes, it includes c(2)M, which encodes a distant α-kleisin family member involved in female meiosis. C(2)M associates in vivo with the Smc3 cohesin subunit, as previously shown for yeast Rec8. In contrast to Rec8, however, C(2)M accumulates predominantly after the pre-meiotic S-phase. Moreover, after association with the synaptonemal complex, it disappears again and cannot be detected on meiotic chromosomes by metaphase I. C(2)M cleavage fragments are not observed during completion of the meiotic divisions, and mutations within putative separase cleavage sites do not interfere with meiotic chromosome segregation. Therefore, C(2)M appears to function within the synaptonemal complex during prophase I but possibly not thereafter. This suggests that C(2)M may not confer sister chromatid cohesion needed for meiosis I and II chromosome segregation.
- Parisi S, McKay MJ, Molnar M, Thompson MA, van der Spek PJ, van Drunen-Schoenmaker E, Kanaar R, Lehmann E, Hoeijmakers JH, Kohli J (1999) Rec8p, a meiotic recombination and sister chromatid cohesion phosphoprotein of the Rad21p family conserved from fission yeast to humans. Mol Cell Biol 19:3515–3528PubMedGoogle Scholar
- Spradling AC (1993) Developmental genetics of oogenesis. In: Bate M, Martinez Arias A (eds) The development of Drosophila melanogaster, vol 1. Cold Spring Harbor Laboratory, Cold Spring Harbor, pp 1–70Google Scholar