RRC ID 73759
Author Sato K, Nishida KM, Shibuya A, Siomi MC, Siomi H.
Title Maelstrom coordinates microtubule organization during Drosophila oogenesis through interaction with components of the MTOC.
Journal Genes Dev
Abstract The establishment of body axes in multicellular organisms requires accurate control of microtubule polarization. Mutations in Drosophila PIWI-interacting RNA (piRNA) pathway genes often disrupt the axes of the oocyte. This results from the activation of the DNA damage checkpoint factor Checkpoint kinase 2 (Chk2) due to transposon derepression. A piRNA pathway gene, maelstrom (mael), is critical for the establishment of oocyte polarity in the developing egg chamber during Drosophila oogenesis. We show that Mael forms complexes with microtubule-organizing center (MTOC) components, including Centrosomin, Mini spindles, and γTubulin. We also show that Mael colocalizes with αTubulin and γTubulin to centrosomes in dividing cyst cells and follicle cells. MTOC components mislocalize in mael mutant germarium and egg chambers, leading to centrosome migration defects. During oogenesis, the loss of mael affects oocyte determination and induces egg chamber fusion. Finally, we show that the axis specification defects in mael mutants are not suppressed by a mutation in mnk, which encodes a Chk2 homolog. These findings suggest a model in which Mael serves as a platform that nucleates other MTOC components to form a functional MTOC in early oocyte development, which is independent of Chk2 activation and DNA damage signaling.
Volume 25(22)
Pages 2361-73
Published 2011-11-15
DOI 10.1101/gad.174110.111
PII 25/22/2361
PMID 22085963
PMC PMC3222902
MeSH Animals Cell Division Centrosome / metabolism Checkpoint Kinase 2 Drosophila / genetics Drosophila / growth & development Drosophila / metabolism Drosophila / physiology* Drosophila Proteins / genetics* Drosophila Proteins / metabolism* Female Microtubule-Organizing Center / metabolism Microtubules / genetics Microtubules / metabolism* Multiprotein Complexes Oogenesis / genetics Oogenesis / physiology* Ovary / cytology Ovary / metabolism Protein Serine-Threonine Kinases / metabolism Protein Transport Tubulin / metabolism
IF 9.527
Drosophila 10010Ab-1 10014Ab-1