Anomalous centriole configurations are detected in Drosophila wing disc cells upon Cdk1 inactivation.
The centriole, organizer of the centrosome, duplicates by assembling a unique daughter identical to itself in overall organization and length. The centriole is a cylindrical structure composed of nine sets of microtubules and is thus predicted to have nine-fold symmetry. During duplication, a daughter lacking discrete microtubular organization first appears off the wall of the mother centriole. It increases in length perpendicularly away from the mother and terminates growth when it matches the length of the mother. How a unique daughter of the correct length and overall organization is assembled is unknown. Here, we describe three types of unusual centriole configurations observed in wing imaginal discs of Drosophila following inactivation of Cdk1. First, we observed centriole triplets consisting of one mother and two daughters, which suggested that centrioles have more than one potential site for the assembly of daughters. Second, we observed centriole triplets comprising a grandmother, mother and daughter, which suggested that subsequent centriole duplication cycles do not require separation of mother and daughter centrioles. Finally, we observed centriole pairs in which the daughter is longer than its mother. These findings suggest that regulatory events rather than rigid structural constraints dictate features of the stereotyped duplication program of centrioles.
Vidwans
Smruti J
SJ
Department of Biochemistry and Biophysics, University of California-San Francisco, 513 Parnassus Avenue, Box 0448, San Francisco, CA 94143, USA.
Wong
Mei Lie
ML
O'Farrell
Patrick H
PH
D000818:Animals; D016203:CDC2 Protein Kinase / Q000172:deficiency* / Q000235:genetics; D018797:Cell Cycle Proteins / Q000235:genetics; D002455:Cell Division / Q000235:genetics*; D002502:Centrioles / Q000235:genetics / Q000473:pathology* / Q000648:ultrastructure; D004331:Drosophila melanogaster / Q000166:cytology / Q000235:genetics / Q000254:growth & development*; D018507:Gene Expression Regulation, Developmental / Q000235:genetics; D018816:Genes, cdc / Q000502:physiology; D007814:Larva / Q000166:cytology / Q000235:genetics / Q000254:growth & development*; D008854:Microscopy, Electron; D008870:Microtubules / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D014921:Wings, Animal / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism
D018797:Cell Cycle Proteins; D016203:CDC2 Protein Kinase