Cell News 04/2018
          
        
        
          15
        
        
          collaborators, the Bourn Hall Clinic in Cambridge and Kiner-
        
        
          wunschzentrum Göttingen, for their invaluable help. Finally, I
        
        
          dedicate this work to all women going through fertility strug-
        
        
          gles who donated their oocytes to our projects over the years. I
        
        
          hope that having my motivation further boosted by Nikon and
        
        
          the DGZ, I will be able to contribute in the coming years to elu-
        
        
          cidating the molecular basis of chromosome mis-segregation
        
        
          in human eggs and improving clinical outcomes for couples
        
        
          struggling with infertility.
        
        
          
            References
          
        
        
          1 Clift, D. & Schuh, M. Restarting life: fertilization and the
        
        
          transition from meiosis to mitosis. Nat Rev Mol Cell Biol 14,
        
        
          549-562, doi:10.1038/nrm3643 (2013).
        
        
          2 Hassold, T. & Hunt, P. To err (meiotically) is human: the
        
        
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          doi:10.1038/35066065 (2001).
        
        
          3 Dunson, D. B., Baird, D. D. & Colombo, B. Increased infertil-
        
        
          ity with age in men and women. Obstet Gynecol 103, 51-56,
        
        
          doi:10.1097/01.AOG.0000100153.24061.45 (2004).
        
        
          4 Webster, A. & Schuh, M. Mechanisms of Aneuploidy
        
        
          in Human Eggs. Trends Cell Biol 27, 55-68, doi:10.1016/j.
        
        
          tcb.2016.09.002 (2017).
        
        
          5 Herbert, M., Kalleas, D., Cooney, D., Lamb, M. & Lister, L.
        
        
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          and trisomy births. Cold Spring Harb Perspect Biol 7, a017970,
        
        
          doi:10.1101/cshperspect.a017970 (2015).
        
        
          6 Angell, R. R. Predivision in human oocytes at meiosis I: a
        
        
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          7 Sakakibara, Y. et al. Bivalent separation into univalents
        
        
          precedes age-related meiosis I errors in oocytes. Nat Commun
        
        
          6, 7550, doi:10.1038/ncomms8550 (2015).
        
        
          8 Yun, Y., Lane, S. I. & Jones, K. T. Premature dyad separation
        
        
          in meiosis II is the major segregation error with maternal age
        
        
          in mouse oocytes. Development 141, 199-208, doi:10.1242/
        
        
          dev.100206 (2014).
        
        
          9 Burkhardt, S. et al. Chromosome Cohesion Established by
        
        
          Rec8-Cohesin in Fetal Oocytes Is Maintained without Detect-
        
        
          able Turnover in Oocytes Arrested for Months in Mice. Curr Biol
        
        
          26, 678-685, doi:10.1016/j.cub.2015.12.073 (2016).
        
        
          10 Chiang, T., Duncan, F. E., Schindler, K., Schultz, R. M. &
        
        
          Lampson, M. A. Evidence that weakened centromere cohesion is
        
        
          a leading cause of age-related aneuploidy in oocytes. Curr Biol
        
        
          20, 1522-1528, doi:10.1016/j.cub.2010.06.069 (2010).
        
        
          11 Shomper, M., Lappa, C. & FitzHarris, G. Kinetochore microtu-
        
        
          bule establishment is defective in oocytes from aged mice. Cell
        
        
          Cycle 13, 1171-1179, doi:10.4161/cc.28046 (2014).
        
        
          12Holubcova, Z., Blayney, M., Elder, K. & Schuh, M. Human
        
        
          oocytes. Error-prone chromosome-mediated spindle assembly
        
        
          favors chromosome segregation defects in human oocytes.
        
        
          Science 348, 1143-1147, doi:10.1126/science.aaa9529 (2015).
        
        
          13 Zielinska, A. P., Holubcova, Z., Blayney, M., Elder, K. & Schuh,
        
        
          M. Sister kinetochore splitting and precocious disintegration
        
        
          of bivalents could explain the maternal age effect. Elife 4,
        
        
          e11389, doi:10.7554/eLife.11389 (2015).
        
        
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          for studying meiosis in live and fixed human oocytes. Meth-
        
        
          ods Cell Biol 145, 315-333, doi:10.1016/bs.mcb.2018.03.039
        
        
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          15 Tsutsumi, M. et al. Age-related decrease of meiotic cohesins
        
        
          in human oocytes. PLoS One 9, e96710, doi:10.1371/journal.
        
        
          pone.0096710 (2014).
        
        
          16 Patel, J., Tan, S. L., Hartshorne, G. M. & McAinsh, A. D.
        
        
          Unique geometry of sister kinetochores in human oocytes
        
        
          during meiosis I may explain maternal age-associated in-
        
        
          creases in chromosomal abnormalities. Biol Open 5, 178-184,
        
        
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            About the author
          
        
        
          Agata Zielinska is studying Medicine with an integrated bache-
        
        
          lor’s degree in Developmental Biology and a PhD in Cell Biology
        
        
          at Trinity College, University of Cambridge, UK. After having
        
        
          successfully completed the first four years of her medical de-
        
        
          gree, she joined Dr Melina Schuh at the MRC Laboratory of Mo-
        
        
          lecular Biology in Cambridge, UK to pursue a PhD degree, with
        
        
          the financial support of the Rosetrees Trust. During the first
        
        
          part of her PhD, she focused on elucidating the causes of de-
        
        
          clining egg quality with advancing female age directly in human
        
        
          eggs. In May 2016, she moved together with the Schuh Lab to
        
        
          the Max Planck Institute for Biophysical Chemistry in Göttingen,
        
        
          Germany to continue her PhD work, this time focusing on devel-
        
        
          oping new tools to study mammalian meiosis. Agata defended
        
        
          her PhD in July 2018 and is currently completing the last steps
        
        
          of her medical training in the UK. She hopes to return to the
        
        
          fascinating world of mammalian meiosis very soon.
        
        
          Carien Niessen and prize winner Agata Zielinska (right)
        
        
          
            NIKON YOUNG SCIENTIST AWARD 2018