The Drosophila pericentrin-like protein is essential for cilia/flagella function, but appears to be dispensable for mitosis

Abstract

Centrosomes consist of a pair of centrioles surrounded by an amorphous pericentriolar material (PCM). Proteins that contain a Pericentrin/AKAP450 centrosomal targeting (PACT) domain have been implicated in recruiting several proteins to the PCM. We show that the only PACT domain protein in Drosophila (the Drosophila pericentrin-like protein [D-PLP]) is associated with both the centrioles and the PCM, and is essential for the efficient centrosomal recruitment of all six PCM components that we tested. Surprisingly, however, all six PCM components are eventually recruited to centrosomes during mitosis in d-plp mutant cells, and mitosis is not dramatically perturbed. Although viable, d-plp mutant flies are severely uncoordinated, a phenotype usually associated with defects in mechanosensory neuron function. We show that the sensory cilia of these neurons are malformed and the neurons are nonfunctional in d-plp mutants. Moreover, the flagella in mutant sperm are nonmotile. Thus, D-PLP is essential for the formation of functional cilia and flagella in flies.

Promoter hijack reveals pericentrin functions in mitosis and the DNA damage response

“…However, γ-tubulin localization to pericentrindeficient centrosomes was reduced, as has been seen in other models. 4,5,7,18 We also observed a significant increase in the proportion of monopolar spindles, but not to the extent observed in knockdown experiments in HeLa cells. 7,18 Knockdown of HeLa PCNT reduced the centrosomal γ-tubulin to approximately 10% of wild-type levels, 18 a more dramatic reduction than we observed and one that could impact sufficiently on centrosome maturation to lead to monopolar spindle formation in almost all cells.…”

“…19,20 In Drosophila, P-element-mediated disruption of the gene encoding the pericentrin ortholog, D-PLP, led to reduced centrosomal accumulation of γ-tubulin and of other centrosome components, although no marked impact on mitosis was observed. 4 Notably, ciliary abnormalities arose in the d-plp mutant flies, a phenotype reflected in the recent description of defective olfactory cilia formation in mice with a gene trap insertion in the 5' untranslated region of the first exon of Pcnt. 21 Together, these data clearly implicate pericentrin in regulatory and signaling functions of the centrosome.…”

“…[1][2][3][4] Pericentrin acts as scaffold within the PCM and interacts with a number of partners, in particular γ-tubulin and other members of the γ-tubulin ring complex, providing a structural framework in which the MTOC activities can occur [5][6][7] (reviewed in ref. 8).…”

Cell biology of polycystin-2

“…For example, deletion of the outer dense finer 2 gene (odf2) in mouse F9 embryonic carcinoma cells resulted in loss of cilia without a measurable effect on cell cycle progression [77]. The same was true for Dsas-4 [71] and AKAP450 [70] in Drosophila. Therefore, deletion of PKD1, PKD2 or even components of the intraflagellar transport (IFT) machinery may not result in increased proliferation in cell culture as would be expected for a typical cystogene.…”

“…While the mechanism by which all these proteins and particularly PKD2, function to assemble cilia is unknown, the study by Jurczyk et al [27] puts forth the very attractive concept, that PKD2 may actually function upstream of ciliary formation, at the level of the centrosome. Recent work in Drosophila has shown that deletion of centrosomal protein AKAP450 [70] and DSas-4 [71], a Drosophila homolog of the centrosomal protein CenpJ, resulted in loss of centrosomes and cilia. Interestingly, loss of centrosomes did not have an effect on mitosis [71].…”