PT  - JOURNAL ARTICLE
AU  - Alexander JR Booth
AU  - Zuojun Yue
AU  - John K Eykelenboom
AU  - Tom Stiff
AU  - GW Gant Luxton
AU  - Helfrid Hochegger
AU  - Tomoyuki U Tanaka
TI  - Contractile acto-myosin network on nuclear envelope remnants positions human chromosomes for mitosis
AID  - 10.1101/459750
DP  - 2019 Jan 01
TA  - bioRxiv
PG  - 459750
4099  - http://biorxiv.org/content/early/2019/01/30/459750.short
4100  - http://biorxiv.org/content/early/2019/01/30/459750.full
AB  - To ensure proper segregation during mitosis, chromosomes must be efficiently captured by kinetochore microtubules and subsequently aligned on the mitotic spindle. The efficacy of chromosome capture by the mitotic spindle can be influenced by how widely chromosomes are scattered in space. Here, we quantify chromosome-scattering volume (CSV) and find that it is reduced immediately after nuclear envelope breakdown (NEBD) in human cells. The reduction of CSV occurs independently of microtubules and is therefore not an outcome of interactions between chromosomes and the spindle. We find that, prior to NEBD, an acto-myosin network is assembled in a LINC complex-dependent manner on the cytoplasmic surface of the nuclear envelope. This acto-myosin network remains around chromosomes soon after NEBD, and its myosin-II-mediated contraction reduces CSV and facilitates chromosome interaction with spindle microtubules.