TY - JOUR T1 - Mother centrioles generate a local pulse of Polo/PLK1 activity to initiate mitotic centrosome assembly JF - bioRxiv DO - 10.1101/2021.10.26.465695 SP - 2021.10.26.465695 AU - Siu-Shing Wong AU - Zachary M. Wilmott AU - Saroj Saurya AU - Felix Y. Zhou AU - Kwai-Yin Chau AU - Alain Goriely AU - Jordan W. Raff Y1 - 2021/01/01 UR - http://biorxiv.org/content/early/2021/10/26/2021.10.26.465695.abstract N2 - Mitotic centrosomes are formed when centrioles recruit large amounts of pericentriolar material (PCM) around themselves. This centrosome “maturation” requires the centrioles and also Polo/PLK1 protein kinase. The PCM comprises several hundred proteins and, in Drosophila, Polo cooperates with the conserved centrosome proteins Spd-2/CEP192 and Cnn/CDK5RAP2 to assemble a PCM scaffold around the mother centriole that then recruits other PCM client proteins. We show here that in Drosophila syncytial blastoderm embryos, centrosomal Polo levels rise and fall during the assembly process—peaking, and then starting to decline, even as levels of the PCM scaffold continue to rise. Experiments and mathematical modelling indicate that a centriolar pulse of Polo activity, potentially generated by the interaction between Polo and its centriole receptor Ana1 (CEP295 in humans), could explain these unexpected scaffold assembly dynamics. We propose that centrioles generate a local pulse of Polo activity prior to mitotic entry to initiate centrosome maturation, explaining why centrioles and Polo/PLK1 are normally essential for this process.Competing Interest StatementThe authors have declared no competing interest. ER -