title: An Amino-Terminal Polo Kinase Interaction Motif Acts in the Regulation of Centrosome Formation and Reveals a Novel Function for centrosomin (cnn) in Drosophila.
abstract: The formation of the pericentriolar matrix (PCM) and a fully functional centrosome in syncytial Drosophila melanogaster embryos requires the rapid transport of Cnn during initiation of the centrosome replication cycle. We show a Cnn and Polo kinase interaction is apparently required during embryogenesis and involves the exon 1A-initiating coding exon, suggesting a subset of Cnn splice variants is regulated by Polo kinase. During PCM formation exon 1A Cnn-Long Form proteins likely bind Polo kinase before phosphorylation by Polo for Cnn transport to the centrosome. Loss of either of these interactions in a portion of the total Cnn protein pool is sufficient to remove native Cnn from the pool, thereby altering the normal localization dynamics of Cnn to the PCM. Additionally, Cnn-Short Form proteins are required for polar body formation, a process known to require Polo kinase after the completion of meiosis. Exon 1A Cnn-LF and Cnn-SF proteins, in conjunction with Polo kinase, are required at the completion of meiosis and for the formation of functional centrosomes during early embryogenesis.
authors.affiliation: Department of Biology, Indiana University, Bloomington, Indiana 47405.
authors.forename: Robert C
authors.initials: RC
authors.lastname: Eisman
authors.affiliation: Department of Biology, Indiana University, Bloomington, Indiana 47405.
authors.forename: Melissa A S
authors.initials: MA
authors.lastname: Phelps
authors.affiliation: Department of Biology, Indiana University, Bloomington, Indiana 47405 kaufman@indiana.edu.
authors.forename: Thomas
authors.identifier: http://orcid.org/0000-0003-1406-7671
authors.initials: T
authors.lastname: Kaufman
mesh_terms: D000818:Animals; D018385:Centrosome / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics* / Q000378:metabolism; D004331:Drosophila melanogaster / Q000235:genetics / Q000254:growth & development; D004625:Embryo, Nonmammalian; D047108:Embryonic Development / Q000235:genetics*; D005091:Exons / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D018398:Homeodomain Proteins / Q000235:genetics* / Q000378:metabolism; D008870:Microtubules / Q000235:genetics / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000235:genetics* / Q000378:metabolism
chemical_list: D029721:Drosophila Proteins; D018398:Homeodomain Proteins; C098130:cnn protein, Drosophila; C072004:polo protein, Drosophila; D017346:Protein Serine-Threonine Kinases
keywords: Drosophila; Polo kinase; centrosomin (cnn); cleavage mitosis; meiosis