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A novel role for the condensin II complex in cellular senescence.

ABSTRACT: Although cellular senescence is accompanied by global alterations in genome architecture, how the genome is restructured during the senescent processes is not well understood. Here, we show that the hCAP-H2 subunit of the condensin II complex exists as either a full-length protein or an N-terminus truncated variant (?N). While the full-length hCAP-H2 associates with mitotic chromosomes, the ?N variant exists as an insoluble nuclear structure. When overexpressed, both hCAP-H2 isoforms assemble this nuclear architecture and induce senescence-associated heterochromatic foci (SAHF). The hCAP-H2?N protein accumulates as cells approach senescence, and hCAP-H2 knockdown inhibits oncogene-induced senescence. This study identifies a novel mechanism whereby condensin drives senescence via nuclear/genomic reorganization.

SUBMITTER: Yokoyama Y

PROVIDER: S-EPMC4613835 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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A novel role for the condensin II complex in cellular senescence.

Yokoyama Yuhki Y Zhu Hengrui H Zhang Rugang R Noma Ken-ichi K

Cell cycle (Georgetown, Tex.) 20150101 13

Although cellular senescence is accompanied by global alterations in genome architecture, how the genome is restructured during the senescent processes is not well understood. Here, we show that the hCAP-H2 subunit of the condensin II complex exists as either a full-length protein or an N-terminus truncated variant (ΔN). While the full-length hCAP-H2 associates with mitotic chromosomes, the ΔN variant exists as an insoluble nuclear structure. When overexpressed, both hCAP-H2 isoforms assemble th ...[more]

PMID: 26017022

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