Ran-GTP assembles a specialized spindle structure for accurate chromosome segregation in medaka early embryos.

ABSTRACT: Despite drastic cellular changes during cleavage, a mitotic spindle assembles in each blastomere to accurately segregate duplicated chromosomes. Mechanisms of mitotic spindle assembly have been extensively studied using small somatic cells. However, mechanisms of spindle assembly in large vertebrate embryos remain little understood. Here, we establish functional assay systems in medaka (Oryzias latipes) embryos by combining CRISPR knock-in with auxin-inducible degron technology. Live imaging reveals several unexpected features of microtubule organization and centrosome positioning that achieve rapid, accurate cleavage. Importantly, Ran-GTP assembles a dense microtubule network at the metaphase spindle center that is essential for chromosome segregation in early embryos. This unique spindle

SUBMITTER: Kiyomitsu A 

PROVIDER: S-EPMC10834446 | biostudies-literature | 2024 Feb

REPOSITORIES: biostudies-literature