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A sensitised RNAi screen reveals a ch-TOG genetic interaction network required for spindle assembly.

ABSTRACT: How multiple spindle assembly pathways are integrated to drive bipolar spindle assembly is poorly understood. We performed an image-based double RNAi screen to identify genes encoding Microtubule-Associated Proteins (MAPs) that interact with the highly conserved ch-TOG gene to regulate bipolar spindle assembly in human cells. We identified a ch-TOG centred network of genetic interactions which promotes centrosome-mediated microtubule polymerisation, leading to the incorporation of microtubules polymerised by all pathways into a bipolar structure [corrected]. Our genetic screen also reveals that ch-TOG maintains a dynamic microtubule population, in part, through modulating HSET activity. ch-TOG ensures that spindle assembly is robust to perturbation but sufficiently dynamic such that spindles can explore a diverse shape space in search of structures that can align chromosomes.

SUBMITTER: Barr AR

PROVIDER: S-EPMC4453164 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature

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A sensitised RNAi screen reveals a ch-TOG genetic interaction network required for spindle assembly.

Barr Alexis R AR Bakal Chris C

Scientific reports 20150603

How multiple spindle assembly pathways are integrated to drive bipolar spindle assembly is poorly understood. We performed an image-based double RNAi screen to identify genes encoding Microtubule-Associated Proteins (MAPs) that interact with the highly conserved ch-TOG gene to regulate bipolar spindle assembly in human cells. We identified a ch-TOG centred network of genetic interactions which promotes centrosome-mediated microtubule polymerisation, leading to the incorporation of microtubules p ...[more]

PMID: 26037491

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