Breuer, ManuelKolano, AgnieszkaKwon, MijungLi, Chao-ChinTsai, Ting-FenPellman, DavidBrunet, StephaneVerlhac, Marie-Helene2011-12-062010Breuer, Manuel, Agnieszka Kolano, Mijung Kwon, Chao-Chin Li, Ting-Fen Tsai, David Pellman, Stephane Brunet, and Marie-Helene Verlhac. 2010. HURP permits MTOC sorting for robust meiotic spindle bipolarity, similar to extra centrosome clustering in cancer cells. Journal of Cell Biology 191(7): 1251-1260.0021-9525http://nrs.harvard.edu/urn-3:HUL.InstRepos:5360613In contrast to somatic cells, formation of acentriolar meiotic spindles relies on the organization of microtubules (MTs) and MT-organizing centers (MTOCs) into a stable bipolar structure. The underlying mechanisms are still unknown. We show that this process is impaired in hepatoma up-regulated protein (Hurp) knockout mice, which are viable but female sterile, showing defective oocyte divisions. HURP accumulates on interpolar MTs in the vicinity of chromosomes via Kinesin-5 activity. By promoting MT stability in the spindle central domain, HURP allows efficient MTOC sorting into distinct poles, providing bipolarity establishment and maintenance. Our results support a new model for meiotic spindle assembly in which HURP ensures assembly of a central MT array, which serves as a scaffold for the genesis of a robust bipolar structure supporting efficient chromosome congression. Furthermore, HURP is also required for the clustering of extra centrosomes before division, arguing for a shared molecular requirement of MTOC sorting in mammalian meiosis and cancer cell division.en-USJournal Article2011-12-0610.1083/jcb.201005065