1926 Research Article yuri gagarin is required for actin, tubulin and basal body functions in Drosophila spermatogenesis Michael J. Texada, Rebecca A. Simonette, Cassidy B. Johnson, William J. Deery and Kathleen M. Beckingham* Department of Biochemistry and Cell Biology, MS-140, Rice University, 6100 South Main Street, Houston, TX 77005, USA *Author for correspondence (e-mail:
[email protected]) Accepted 20 March 2008 Journal of Cell Science 121, 1926-1936 Published by The Company of Biologists 2008 doi:10.1242/jcs.026559 Summary Males of the genus Drosophila produce sperm of remarkable the yuri mutant, late clusters of syncytial nuclei are deformed length. Investigation of giant sperm production in Drosophila and disorganized. The basal bodies are also mispositioned on melanogaster has demonstrated that specialized actin and the nuclei, and the association of a specialized structure, the microtubule structures play key roles. The gene yuri gagarin centriolar adjunct (CA), with the basal body is lost. Some of (yuri) encodes a novel protein previously identified through its these nuclear defects might underlie a further unexpected role in gravitaxis. A male-sterile mutation of yuri has revealed abnormality: sperm nuclei occasionally locate to the wrong ends roles for Yuri in the functions of the actin and tubulin structures of the spermatid cysts. The structure of the axonemes that grow of spermatogenesis. Yuri is a component of the motile actin cones out from the basal bodies is affected in the yuri mutant, that individualize the spermatids and is essential for their suggesting a possible role for the CA in axoneme formation. formation. Furthermore, Yuri is required for actin accumulation in the dense complex, a microtubule-rich structure on the sperm Key words: Drosophila, Spermatogenesis, Actin, Tubulin, Basal nuclei thought to strengthen the nuclei during elongation.