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bioRxiv · 10.1101/2024.07.29.605660

The Unkempt RNA binding protein reveals a local translation program in centriole overduplication

Martinez, A.·Stemm-Wolf, A. J.·Sheridan, R. M.·Taliaferro, M.·Pearson, C. G.
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Abstract

Excess centrosomes cause defects in mitosis, cell-signaling, and cell migration, and therefore their assembly is tightly regulated. Plk4 controls centriole duplication at the heart of centrosome assembly, and elevation of Plk4 promotes centrosome amplification (CA), a founding event of tumorigenesis. Here, we investigate the transcriptional consequences of elevated Plk4 and find Unkempt, a gene encoding an RNA binding protein with roles in translational regulation, to be one of only two upregulated mRNAs. Unk protein localizes to centrosomes and Cep131-positive centriolar satellites and is required for Plk4-induced centriole overduplication in an RNA-binding dependent manner. Translation is enriched at centrosomes and centriolar satellites with Unk and Cep131 promoting this localized translation. A transient centrosomal downregulation of translation occurs early in Plk4-induced CA. CNOT9, an Unk interactor and component of the translational inhibitory CCR4-NOT complex, localizes to centrosomes at this time. In summary, centriolar satellites and Unk promote local translation as part of a translational program that ensures centriole duplication.

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Martinez, A., Stemm-Wolf, A. J., Sheridan, R. M., Taliaferro, M., Pearson, C. G.. 2024-07-30. The Unkempt RNA binding protein reveals a local translation program in centriole overduplication. https://doi.org/10.1101/2024.07.29.605660

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