Chromosome Cohesion Established by Rec8-Cohesin in Fetal Oocytes Is Maintained without Detectable Turnover in Oocytes Arrested for Months in Mice

• DOI: 10.1016/j.cub.2015.12.073
• Publication Date: 2016-02-20T02:07:18Z
• Authors: Sabrina Burkhardt; Máté Borsos; Anna Szydlowska; Jonathan Godwin; Suzannah A. Williams; Paula E. Cohen; Takayuki Hirota; Mitinori Saitou; Kikuë Tachibana-K...
• Keywords: 570; Chromosomal Proteins, Non-Histone; cohesin; Cell Cycle Proteins; Mice; 03 medical and health sciences; Phosphoproteins/genetics; Report; Chromosome Segregation; meiosis; oocytes; Animals; Cohesins; Cell Cycle Proteins/genetics; 0303 health sciences; Agricultural and Biological Sciences(all); Biochemistry, Genetics and Molecular Biology(all); Oocytes/metabolism; Nuclear Proteins; Phosphoproteins; Chromosomal Proteins; Nuclear Proteins/genetics; Non-Histone/genetics; Oocytes; Female

Sister chromatid cohesion mediated by the cohesin complex is essential for chromosome segregation in mitosis and meiosis [1]. Rec8-containing cohesin, bound to Smc3/Smc1α or Smc3/Smc1β, maintains bivalent mammalian [2-6]. In females, meiotic DNA replication recombination occur fetal oocytes. After birth, oocytes arrest at prolonged dictyate stage until recruited grow into mature that divide ovulation. How maintained arrested remains a pivotal question relevant maternal age-related aneuploidy. Hypothetically, turnover regenerates Evidence post-replicative establishment mechanism exists, yeast invertebrates [7, 8]. mouse oocytes, loading factor Nipbl/Scc2 localizes axes during [9, 10]. Alternatively, without turnover. Consistent with this, maintenance does not require Smc1β transcription, but unlike Rec8, required establishing [11, 12]. Rec8 weeks of oocyte growth [3]. Whether same applies months decades unknown. Here, we test whether activated builds revealed TEV cleavage live-cell imaging. establishes when using tamoxifen-inducible Cre. contrast, no new detected tamoxifen despite synthesis. We conclude established detectable dictyate-arrested This implies women's fertility depends on longevity proteins utero.