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A liquid-like spindle domain promotes acentrosomal spindle assembly in mammalian oocytes.

ABSTRACT: Mammalian oocytes segregate chromosomes with a microtubule spindle that lacks centrosomes, but the mechanisms by which acentrosomal spindles are organized and function are largely unclear. In this study, we identify a conserved subcellular structure in mammalian oocytes that forms by phase separation. This structure, which we term the liquid-like meiotic spindle domain (LISD), permeates the spindle poles and forms dynamic protrusions that extend well beyond the spindle. The LISD selectively concentrates multiple microtubule regulatory factors and allows them to diffuse rapidly within the spindle volume. Disruption of the LISD via different means disperses these factors and leads to severe spindle assembly defects. Our data suggest a model whereby the LISD promotes meiotic spindle assembly by serving as a reservoir that sequesters and mobilizes microtubule regulatory factors in proximity to spindle microtubules.

SUBMITTER: So C

PROVIDER: S-EPMC6629549 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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A liquid-like spindle domain promotes acentrosomal spindle assembly in mammalian oocytes.

So Chun C Seres K Bianka KB Steyer Anna M AM Mönnich Eike E Clift Dean D Pejkovska Anastasija A Möbius Wiebke W Schuh Melina M

Science (New York, N.Y.) 20190601 6447

Mammalian oocytes segregate chromosomes with a microtubule spindle that lacks centrosomes, but the mechanisms by which acentrosomal spindles are organized and function are largely unclear. In this study, we identify a conserved subcellular structure in mammalian oocytes that forms by phase separation. This structure, which we term the liquid-like meiotic spindle domain (LISD), permeates the spindle poles and forms dynamic protrusions that extend well beyond the spindle. The LISD selectively conc ...[more]

PMID: 31249032

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