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Dyskerin, tRNA genes, and condensin tether pericentric chromatin to the spindle axis in mitosis.

ABSTRACT: Condensin is enriched in the pericentromere of budding yeast chromosomes where it is constrained to the spindle axis in metaphase. Pericentric condensin contributes to chromatin compaction, resistance to microtubule-based spindle forces, and spindle length and variance regulation. Condensin is clustered along the spindle axis in a heterogeneous fashion. We demonstrate that pericentric enrichment of condensin is mediated by interactions with transfer ribonucleic acid (tRNA) genes and their regulatory factors. This recruitment is important for generating axial tension on the pericentromere and coordinating movement between pericentromeres from different chromosomes. The interaction between condensin and tRNA genes in the pericentromere reveals a feature of yeast centromeres that has profound implications for the function and evolution of mitotic segregation mechanisms.

SUBMITTER: Snider CE

PROVIDER: S-EPMC4210444 | biostudies-other | 2014 Oct

REPOSITORIES: biostudies-other

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Dyskerin, tRNA genes, and condensin tether pericentric chromatin to the spindle axis in mitosis.

Snider Chloe E CE Stephens Andrew D AD Kirkland Jacob G JG Hamdani Omar O Kamakaka Rohinton T RT Bloom Kerry K

The Journal of cell biology 20141020 2

Condensin is enriched in the pericentromere of budding yeast chromosomes where it is constrained to the spindle axis in metaphase. Pericentric condensin contributes to chromatin compaction, resistance to microtubule-based spindle forces, and spindle length and variance regulation. Condensin is clustered along the spindle axis in a heterogeneous fashion. We demonstrate that pericentric enrichment of condensin is mediated by interactions with transfer ribonucleic acid (tRNA) genes and their regula ...[more]

PMID: 25332162

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