Pericentriolar matrix integrity relies on cenexin and Polo-Like Kinase (PLK)1

Aljiboury, A. A.; Mujcic, A.; Curtis, E.; Cammerino, T.; Magny, D.; Lan, Y.; Bates, M.; Freshour, J.; Ahmed-Braimah, Y. H.; Hehnly, H.

doi:10.1101/2022.01.09.475500

bioRxiv · 10.1101/2022.01.09.475500

Pericentriolar matrix integrity relies on cenexin and Polo-Like Kinase (PLK)1

Aljiboury, A. A.·Mujcic, A.·Curtis, E.·Cammerino, T.·Magny, D.·Lan, Y.·Bates, M.·Freshour, J.·Ahmed-Braimah, Y. H.·Hehnly, H.

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Abstract

Polo-Like-Kinase (PLK) 1 activity is associated with maintaining the functional and physical properties of the centrosomes pericentriolar matrix (PCM). In this study, we use a multimodal approach of human cells (HeLa) and zebrafish embryos in parallel to phylogenic analysis to test the role of a PLK1 binding protein, cenexin, in regulating the PCM. Our studies identify that cenexin is required for tempering microtubule nucleation and that a conserved C-terminal PLK1 binding site between humans and zebrafish is needed for PCM maintenance through mediating PLK1-dependent substrate phosphorylation events. PCM architecture in cenexin-depleted zebrafish embryos was rescued with wild-type human cenexin, but not with a C-terminal cenexin mutant (S796A) deficient in PLK1 binding. We propose a model where cenexins C-terminus acts in a conserved manner in eukaryotes, excluding nematodes and arthropods, to anchor PLK1 moderating its potential to phosphorylate PCM substrates required for PCM maintenance and function.

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Aljiboury, A. A., Mujcic, A., Curtis, E., Cammerino, T., Magny, D., Lan, Y., Bates, M., Freshour, J., Ahmed-Braimah, Y. H., Hehnly, H.. 2022-01-11. Pericentriolar matrix integrity relies on cenexin and Polo-Like Kinase (PLK)1. https://doi.org/10.1101/2022.01.09.475500

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