title: Prostaglandins temporally regulate cytoplasmic actin bundle formation during Drosophila oogenesis.
abstract: Prostaglandins (PGs)--lipid signals produced downstream of cyclooxygenase (COX) enzymes--regulate actin dynamics in cell culture and platelets, but their roles during development are largely unknown. Here we define a new role for Pxt, the Drosophila COX-like enzyme, in regulating the actin cytoskeleton--temporal restriction of actin remodeling during oogenesis. PGs are required for actin filament bundle formation during stage 10B (S10B). In addition, loss of Pxt results in extensive early actin remodeling, including actin filaments and aggregates, within the posterior nurse cells of S9 follicles; wild-type follicles exhibit similar structures at a low frequency. Hu li tai shao (Hts-RC) and Villin (Quail), an actin bundler, localize to all early actin structures, whereas Enabled (Ena), an actin elongation factor, preferentially localizes to those in pxt mutants. Reduced Ena levels strongly suppress early actin remodeling in pxt mutants. Furthermore, loss of Pxt results in reduced Ena localization to the sites of bundle formation during S10B. Together these data lead to a model in which PGs temporally regulate actin remodeling during Drosophila oogenesis by controlling Ena localization/activity, such that in S9, PG signaling inhibits, whereas at S10B, it promotes Ena-dependent actin remodeling.
authors.affiliation: Anatomy and Cell Biology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242 Department of Epidemiology, College of Public Health, University of Iowa, Iowa City, IA 52242.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Spracklen
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Kelpsch
authors.forename: Xiang
authors.initials: X
authors.lastname: Chen
authors.forename: Cassandra N
authors.initials: CN
authors.lastname: Spracklen
authors.forename: Tina L
authors.initials: TL
authors.lastname: Tootle
mesh_terms: D008841:Actin Cytoskeleton; D000199:Actins / Q000378:metabolism*; D000818:Animals; D002148:Calmodulin-Binding Proteins / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004330:Drosophila / Q000196:embryology*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism; D005260:Female; D008840:Microfilament Proteins / Q000378:metabolism; D009865:Oocytes / Q000254:growth & development; D009866:Oogenesis / Q000235:genetics*; D006080:Ovarian Follicle / Q000196:embryology; D010544:Peroxidases / Q000235:genetics / Q000378:metabolism; D011453:Prostaglandins / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D000199:Actins; D002148:Calmodulin-Binding Proteins; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; C092744:ENA-VASP proteins; D008840:Microfilament Proteins; D011453:Prostaglandins; C108208:hts protein, Drosophila; C026615:villin; D010544:Peroxidases; C529210:Pxt protein, Drosophila