| First Author | Gómez R | Year | 2014 |
| Journal | Chromosoma | Volume | 123 |
| Issue | 1-2 | Pages | 129-46 |
| PubMed ID | 24013524 | Mgi Jnum | J:344797 |
| Mgi Id | MGI:6760758 | Doi | 10.1007/s00412-013-0434-9 |
| Citation | Gomez R, et al. (2014) Cohesin removal precedes topoisomerase IIalpha-dependent decatenation at centromeres in male mammalian meiosis II. Chromosoma 123(1-2):129-46 |
| abstractText | Sister chromatid cohesion is regulated by cohesin complexes and topoisomerase IIalpha. Although relevant studies have shed some light on the relationship between these two mechanisms of cohesion during mammalian mitosis, their interplay during mammalian meiosis remains unknown. In the present study, we have studied the dynamics of topoisomerase IIalpha in relation to that of the cohesin subunits RAD21 and REC8, the shugoshin-like 2 (Schizosaccharomyces pombe) (SGOL2) and the polo-like kinase 1-interacting checkpoint helicase (PICH), during both male mouse meiotic divisions. Our results strikingly show that topoisomerase IIalpha appears at stretched strands connecting the sister kinetochores of segregating early anaphase II chromatids, once the cohesin complexes have been removed from the centromeres. Moreover, the number and length of these topoisomerase IIalpha-connecting strands increase between lagging chromatids at anaphase II after the chemical inhibition of the enzymatic activity of topoisomerase IIalpha by etoposide. Our results also show that the etoposide-induced inhibition of topoisomerase IIalpha is not able to rescue the loss of centromere cohesion promoted by the absence of the shugoshin SGOL2 during anaphase I. Taking into account our results, we propose a two-step model for the sequential release of centromeric cohesion during male mammalian meiosis II. We suggest that the cohesin removal is a prerequisite for the posterior topoisomerase IIalpha-mediated resolution of persisting catenations between segregating chromatids during anaphase II. |
