Role of CAP350 in centriolar tubule stability and centriole assembly.
BACKGROUND
Centrioles are microtubule-based cylindrical structures composed of nine triplet tubules and are required for the formation of the centrosome, flagella and cilia. Despite theirs importance, centriole biogenesis is poorly understood. Centrosome duplication is initiated at the G1/S transition by the sequential recruitment of a set of conserved proteins under the control of the kinase Plk4. Subsequently, the procentriole is assembled by the polymerization of centriolar tubules via an unknown mechanism involving several tubulin paralogs.


RESULTS
Here, we developed a cellular assay to study centrosome duplication and procentriole stability based on its sensitivity to the microtubule-depolymerizing drug nocodazole. By using RNA interference experiments, we show that the stability of growing procentrioles is regulated by the microtubule-stabilizing protein CAP350, independently of hSAS-6 and CPAP which initiate procentriole growth. Furthermore, our analysis reveals the critical role of centriolar tubule stability for an efficient procentriole growth.


CONCLUSIONS
CAP350 belongs to a new class of proteins which associate and stabilize centriolar tubules to control centriole duplication.
Le Clech
Mikael
M
Department of Cell Biology, Max Planck Institute of Biochemistry, Martinsried, Germany. mikael.leclech@igh.cnrs.fr
D002453:Cell Cycle; D018797:Cell Cycle Proteins / Q000378:metabolism; D045744:Cell Line, Tumor; D002502:Centrioles / Q000378:metabolism*; D018385:Centrosome / Q000378:metabolism*; D006801:Humans; D008868:Microtubule Proteins / Q000378:metabolism*; D008870:Microtubules / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D034622:RNA Interference
D018797:Cell Cycle Proteins; D008868:Microtubule Proteins; C497202:SASS6 protein, human; D017346:Protein Serine-Threonine Kinases