1. Fascin regulates nuclear actin duringDrosophilaoogenesis
- Author
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Tina L. Tootle, Sweta Sudhir, Tiffany N. Fagan, Christopher M. Groen, and Daniel J. Kelpsch
- Subjects
0301 basic medicine ,macromolecular substances ,03 medical and health sciences ,Oogenesis ,0302 clinical medicine ,medicine ,Animals ,Drosophila Proteins ,Molecular Biology ,Actin ,Fascin ,Cell Nucleus ,biology ,Nuclear Functions ,Microfilament Proteins ,Ovary ,Articles ,Cell Biology ,Microfilament Protein ,Cofilin ,Actins ,3. Good health ,Cell biology ,Cell nucleus ,030104 developmental biology ,medicine.anatomical_structure ,Actin Depolymerizing Factors ,Profilin ,Oocytes ,biology.protein ,Drosophila ,Female ,Nuclear transport ,Carrier Proteins ,030217 neurology & neurosurgery ,Drosophila Protein - Abstract
Study of Drosophila oogenesis reveals that the nuclear localization of actin is controlled by both development and Fascin. Fascin regulates both endogenous nuclear actin and ectopic nuclear actin rod formation by controlling Cofilin., Drosophila oogenesis provides a developmental system with which to study nuclear actin. During Stages 5–9, nuclear actin levels are high in the oocyte and exhibit variation within the nurse cells. Cofilin and Profilin, which regulate the nuclear import and export of actin, also localize to the nuclei. Expression of GFP-tagged Actin results in nuclear actin rod formation. These findings indicate that nuclear actin must be tightly regulated during oogenesis. One factor mediating this regulation is Fascin. Overexpression of Fascin enhances nuclear GFP-Actin rod formation, and Fascin colocalizes with the rods. Loss of Fascin reduces, whereas overexpression of Fascin increases, the frequency of nurse cells with high levels of nuclear actin, but neither alters the overall nuclear level of actin within the ovary. These data suggest that Fascin regulates the ability of specific cells to accumulate nuclear actin. Evidence indicates that Fascin positively regulates nuclear actin through Cofilin. Loss of Fascin results in decreased nuclear Cofilin. In addition, Fascin and Cofilin genetically interact, as double heterozygotes exhibit a reduction in the number of nurse cells with high nuclear actin levels. These findings are likely applicable beyond Drosophila follicle development, as the localization and functions of Fascin and the mechanisms regulating nuclear actin are widely conserved.
- Published
- 2016