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. 1994 Apr 2;125(2):369–380. doi: 10.1083/jcb.125.2.369

Drosophila singed, a fascin homolog, is required for actin bundle formation during oogenesis and bristle extension

PMCID: PMC2120035  PMID: 8163553

Abstract

Drosophila singed mutants were named for their gnarled bristle phenotype but severe alleles are also female sterile. Recently, singed protein was shown to have 35% peptide identity with echinoderm fascin. Fascin is found in actin filament bundles in microvilli of sea urchin eggs and in filopodial extensions in coelomocytes. We show that Drosophila singed is required for actin filament bundle formation in the cytoplasm of nurse cells during oogenesis; in severe mutants, the absence of cytoplasmic actin filament bundles allows nurse cell nuclei to lodge in ring canals and block nurse cell cytoplasm transport. Singed is also required for organized actin filament bundle formation in the cellular extension that forms a bristle; in severe mutants, the small disorganized actin filament bundles lack structural integrity and allow bristles to bend and branch during extension. Singed protein is also expressed in migratory cells of the developing egg chamber and in the socket cell of the developing bristle, but no defect is observed in these cells in singed mutants. Purified, bacterially expressed singed protein bundles actin filaments in vitro with the same stoichiometry reported for purified sea urchin fascin. Singed-saturated actin bundles have a molar ratio of singed/actin of approximately 1:4.3 and a transverse cross-banding pattern of 12 nm seen using electron microscopy. Our results suggest that singed protein is required for actin filament bundle formation and is a Drosophila homolog of echinoderm fascin.

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Selected References

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  1. Appel L. F., Prout M., Abu-Shumays R., Hammonds A., Garbe J. C., Fristrom D., Fristrom J. The Drosophila Stubble-stubbloid gene encodes an apparent transmembrane serine protease required for epithelial morphogenesis. Proc Natl Acad Sci U S A. 1993 Jun 1;90(11):4937–4941. doi: 10.1073/pnas.90.11.4937. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Bender H A. Studies on the Expression of Various Singed Alleles in Drosophila Melanogaster. Genetics. 1960 Jul;45(7):867–883. doi: 10.1093/genetics/45.7.867. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Bryan J., Edwards R., Matsudaira P., Otto J., Wulfkuhle J. Fascin, an echinoid actin-bundling protein, is a homolog of the Drosophila singed gene product. Proc Natl Acad Sci U S A. 1993 Oct 1;90(19):9115–9119. doi: 10.1073/pnas.90.19.9115. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Bryan J., Kane R. E. Separation and interaction of the major components of sea urchin actin gel. J Mol Biol. 1978 Oct 25;125(2):207–224. doi: 10.1016/0022-2836(78)90345-5. [DOI] [PubMed] [Google Scholar]
  5. Cooley L., Verheyen E., Ayers K. chickadee encodes a profilin required for intercellular cytoplasm transport during Drosophila oogenesis. Cell. 1992 Apr 3;69(1):173–184. doi: 10.1016/0092-8674(92)90128-y. [DOI] [PubMed] [Google Scholar]
  6. DeRosier D. J., Censullo R. Structure of F-actin needles from extracts of sea urchin oocytes. J Mol Biol. 1981 Feb 15;146(1):77–99. doi: 10.1016/0022-2836(81)90367-3. [DOI] [PubMed] [Google Scholar]
  7. DeRosier D., Mandelkow E., Silliman A. Structure of actin-containing filaments from two types of non-muscle cells. J Mol Biol. 1977 Jul 15;113(4):679–695. doi: 10.1016/0022-2836(77)90230-3. [DOI] [PubMed] [Google Scholar]
  8. Gutzeit H. O. The role of microfilaments in cytoplasmic streaming in Drosophila follicles. J Cell Sci. 1986 Feb;80:159–169. doi: 10.1242/jcs.80.1.159. [DOI] [PubMed] [Google Scholar]
  9. Hoover K. K., Chien A. J., Corces V. G. Effects of transposable elements on the expression of the forked gene of Drosophila melanogaster. Genetics. 1993 Oct;135(2):507–526. doi: 10.1093/genetics/135.2.507. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Kane R. E. Actin polymerization and interaction with other proteins in temperature-induced gelation of sea urchin egg extracts. J Cell Biol. 1976 Dec;71(3):704–714. doi: 10.1083/jcb.71.3.704. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
  12. Maekawa S., Endo S., Sakai H. A protein in starfish sperm head which bundles actin filaments in vitro: purification and characterization. J Biochem. 1982 Dec;92(6):1959–1972. doi: 10.1093/oxfordjournals.jbchem.a134127. [DOI] [PubMed] [Google Scholar]
  13. Montell D. J., Rorth P., Spradling A. C. slow border cells, a locus required for a developmentally regulated cell migration during oogenesis, encodes Drosophila C/EBP. Cell. 1992 Oct 2;71(1):51–62. doi: 10.1016/0092-8674(92)90265-e. [DOI] [PubMed] [Google Scholar]
  14. Otto J. J., Kane R. E., Bryan J. Formation of filopodia in coelomocytes: localization of fascin, a 58,000 dalton actin cross-linking protein. Cell. 1979 Jun;17(2):285–293. doi: 10.1016/0092-8674(79)90154-5. [DOI] [PubMed] [Google Scholar]
  15. Otto J. J., Kane R. E., Bryan J. Redistribution of actin and fascin in sea urchin eggs after fertilization. Cell Motil. 1980;1(1):31–40. doi: 10.1002/cm.970010104. [DOI] [PubMed] [Google Scholar]
  16. Otto J. J., Schroeder T. E. Assembly-disassembly of actin bundles in starfish oocytes: an analysis of actin-associated proteins in the isolated cortex. Dev Biol. 1984 Feb;101(2):263–273. doi: 10.1016/0012-1606(84)90140-4. [DOI] [PubMed] [Google Scholar]
  17. Overton J. The fine structure of developing bristles in wild type and mutant Drosophila melanogaster. J Morphol. 1967 Aug;122(4):367–379. doi: 10.1002/jmor.1051220406. [DOI] [PubMed] [Google Scholar]
  18. Paterson J., O'Hare K. Structure and transcription of the singed locus of Drosophila melanogaster. Genetics. 1991 Dec;129(4):1073–1084. doi: 10.1093/genetics/129.4.1073. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Perrimon N., Gans M. Clonal analysis of the tissue specificity of recessive female-sterile mutations of Drosophila melanogaster using a dominant female-sterile mutation Fs(1)K1237. Dev Biol. 1983 Dec;100(2):365–373. doi: 10.1016/0012-1606(83)90231-2. [DOI] [PubMed] [Google Scholar]
  20. Petersen N. S., Lankenau D. H., Mitchell H. K., Young P., Corces V. G. forked proteins are components of fiber bundles present in developing bristles of Drosophila melanogaster. Genetics. 1994 Jan;136(1):173–182. doi: 10.1093/genetics/136.1.173. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Roiha H., Rubin G. M., O'Hare K. P element insertions and rearrangements at the singed locus of Drosophila melanogaster. Genetics. 1988 May;119(1):75–83. doi: 10.1093/genetics/119.1.75. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Schweisguth F., Posakony J. W. Suppressor of Hairless, the Drosophila homolog of the mouse recombination signal-binding protein gene, controls sensory organ cell fates. Cell. 1992 Jun 26;69(7):1199–1212. doi: 10.1016/0092-8674(92)90641-o. [DOI] [PubMed] [Google Scholar]
  23. Smith D. B., Johnson K. S. Single-step purification of polypeptides expressed in Escherichia coli as fusions with glutathione S-transferase. Gene. 1988 Jul 15;67(1):31–40. doi: 10.1016/0378-1119(88)90005-4. [DOI] [PubMed] [Google Scholar]
  24. Spudich J. A., Amos L. A. Structure of actin filament bundles from microvilli of sea urchin eggs. J Mol Biol. 1979 Apr 5;129(2):319–331. doi: 10.1016/0022-2836(79)90285-7. [DOI] [PubMed] [Google Scholar]
  25. Spudich J. A., Watt S. The regulation of rabbit skeletal muscle contraction. I. Biochemical studies of the interaction of the tropomyosin-troponin complex with actin and the proteolytic fragments of myosin. J Biol Chem. 1971 Aug 10;246(15):4866–4871. [PubMed] [Google Scholar]
  26. Stokes D. L., DeRosier D. J. Growth conditions control the size and order of actin bundles in vitro. Biophys J. 1991 Feb;59(2):456–465. doi: 10.1016/S0006-3495(91)82239-1. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Xue F., Cooley L. kelch encodes a component of intercellular bridges in Drosophila egg chambers. Cell. 1993 Mar 12;72(5):681–693. doi: 10.1016/0092-8674(93)90397-9. [DOI] [PubMed] [Google Scholar]
  28. Yamashiro-Matsumura S., Matsumura F. Intracellular localization of the 55-kD actin-bundling protein in cultured cells: spatial relationships with actin, alpha-actinin, tropomyosin, and fimbrin. J Cell Biol. 1986 Aug;103(2):631–640. doi: 10.1083/jcb.103.2.631. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Yamashiro-Matsumura S., Matsumura F. Purification and characterization of an F-actin-bundling 55-kilodalton protein from HeLa cells. J Biol Chem. 1985 Apr 25;260(8):5087–5097. [PubMed] [Google Scholar]

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