Ki-67 is a PP1-interacting protein that organises the mitotic chromosome periphery

Booth, Daniel G; Takagi, Masatoshi; Sanchez-Pulido, Luis; Petfalski, Elizabeth; Vargiu, Giulia; Samejima, Kumiko; Imamoto, Naoko; Ponting, Chris P; Tollervey, David; Earnshaw, William C; Vagnarelli, Paola

Abstract

When the nucleolus disassembles during open mitosis, many nucleolar proteins and RNAs associate with chromosomes, establishing a perichromosomal compartment coating the chromosome periphery. At present nothing is known about the function of this poorly characterised compartment. In this study, we report that the nucleolar protein Ki-67 is required for the assembly of the perichromosomal compartment in human cells. Ki-67 is a cell-cycle regulated protein phosphatase 1-binding protein that is involved in phospho-regulation of the nucleolar protein B23/nucleophosmin. Following siRNA depletion of Ki-67, NIFK, B23, nucleolin, and four novel chromosome periphery proteins all fail to associate with the periphery of human chromosomes. Correlative light and electron microscopy (CLEM) images suggest a near-complete loss of the entire perichromosomal compartment. Mitotic chromosome condensation and intrinsic structure appear normal in the absence of the perichromosomal compartment but significant differences in nucleolar reassembly and nuclear organisation are observed in post-mitotic cells.

Citation

Booth, D. G., Takagi, M., Sanchez-Pulido, L., Petfalski, E., Vargiu, G., Samejima, K., Imamoto, N., Ponting, C. P., Tollervey, D., Earnshaw, W. C., & Vagnarelli, P. (2014). Ki-67 is a PP1-interacting protein that organises the mitotic chromosome periphery. eLife, 3, Article e01641. https://doi.org/10.7554/elife.01641

• Journal Article Type: Article
• Acceptance Date: Apr 27, 2014
• Online Publication Date: May 27, 2014
• Publication Date: May 27, 2014
• Deposit Date: Jan 15, 2021
• Publicly Available Date: Jan 18, 2021
• Journal: eLife
• Electronic ISSN: 2050-084X
• Publisher: eLife Sciences Publications
• Peer Reviewed: Peer Reviewed
• Volume: 3
• Article Number: e01641
• DOI: https://doi.org/10.7554/elife.01641
• Keywords: General Biochemistry, Genetics and Molecular Biology; General Immunology and Microbiology; General Neuroscience; General Medicine
• Public URL: https://nottingham-repository.worktribe.com/output/5224325
• Publisher URL: https://elifesciences.org/articles/01641
• Additional Information: Received: 2013-10-05; Accepted: 2014-04-27; Published: 2014-05-27