Biology; Cell Biology; Drosophila; Genetics; Actin Cytoskeleton; Molecular Biology; Oogenesis
We are interested in the cellular mechanisms that underlie polarity and cell growth during development. Our research is focused on understanding how maternal components are made and delivered to oocytes during Drosophila oogenesis. Using mutants with incomplete oocyte growth, we have discovered key roles for the actin cytoskeleton. For example, the ring canals connecting growing oocytes with their nurse cells are stabilized by a special population of bundled actin filaments.
The dramatic growth of ring canals during oogenesis requires both actin polymerization and depolymerization, making ring canals a valuable model for in vivo actin dynamics. The polarized movement of maternal mRNA and protein through ring canals from nurse cells to the oocyte is highly regulated. We identified proteins specifically targeted to the oocyte by GFP protein trapping; we are determining the mechanism of targeting using both live imaging and molecular dissection of the proteins to identify localization signals.
Specialized Terms: Molecular Genetics of Drosophila Oogenesis; Actin Cytoskeleton Regulation; Drosophila; Oogenesis; Ring Canal; Ovarian Muscle Function
Extensive Research Description
Gametes are the ultimate stem cells with the capacity to produce entire
new organisms. We study cellular mechanisms of gamete development using
Drosophila as a model system. We are focused on the development of
female germline cells, from their early differentiation into oocytes or
nurse cells, through the control of oocyte growth during oogenesis. In
addition, we study the role of ovarian muscles in the progression of
developing egg chambers through the ovary.
Early germline development in animals, including flies, relies on a non-canonical form of mitosis. Daughters of germline stem cells undergo a tightly controlled number of mitotic cell divisions with incomplete cytokinesis so that bridges of cytoplasm remain to connect clusters of sister cells. These residual connections are transformed into stable intercellular junctions called ring canals, which are needed for oocyte growth.
In females, this transformation involves recruiting a highly dynamic actin cytoskeleton and many associated actin-binding proteins. Using a variety of genetic and molecular approaches, we have identified many ring canal proteins, and we are actively working toward characterizing their functions. We are also studying the role of ring canals in the polarized transport of maternal mRNAs, proteins and organelles from nurse cells and to the oocyte.
While ring canals are ubiquitous in germline cells, their presence and function in somatic cells are largely unexplored. In order to understand how these fascinating structures contribute to the biology of non-germline cells, we are characterizing somatic ring canals in epithelial cells of the Drosophila ovary and imaginal discs using cell biology and genetics.
Recently we discovered a novel muscle type in the Drosophila ovary that contains striated sarcomeres, but only a single nucleus. This indicates the muscles did not form by typical myoblast fusion. Importantly, the presence of one nucleus means we can use powerful genetic clonal analysis to analyze the effects of mutations affecting muscle proteins, including those associated with human musclular dystrophy. In addition, we can study proliferation of these muscles in adults and the pool of progenitor stem cells that supply new muscle cells in adults.
Full List of PubMed Publications
- Cooley L: How Primordial Germ Cells Destroy Somatic Signals. Dev Cell. 2017 Jul 24. PMID: 28742996
- Hudson AM, Mannix KM, Cooley L: Actin Cytoskeletal Organization in Drosophila Germline Ring Canals Depends on Kelch Function in a Cullin-RING E3 Ligase. Genetics. 2015 Nov; 2015 Sep 16. PMID: 26384358
- Perkins LA, Holderbaum L, Tao R, Hu Y, Sopko R, McCall K, Yang-Zhou D, Flockhart I, Binari R, Shim HS, Miller A, Housden A, Foos M, Randkelv S, Kelley C, Namgyal P, Villalta C, Liu LP, Jiang X, Huan-Huan Q, Wang X, Fujiyama A, Toyoda A, Ayers K, Blum A, Czech B, Neumuller R, Yan D, Cavallaro A, Hibbard K, Hall D, Cooley L, Hannon GJ, Lehmann R, Parks A, Mohr SE, Ueda R, Kondo S, Ni JQ, Perrimon N: The Transgenic RNAi Project at Harvard Medical School: Resources and Validation. Genetics. 2015 Nov; 2015 Aug 28. PMID: 26320097
- Burn KM, Shimada Y, Ayers K, Vemuganti S, Lu F, Hudson AM, Cooley L: Somatic insulin signaling regulates a germline starvation response in Drosophila egg chambers. Dev Biol. 2015 Feb 15; 2014 Dec 3. PMID: 25481758
- Heisig M, Abraham NM, Liu L, Neelakanta G, Mattessich S, Sultana H, Shang Z, Ansari JM, Killiam C, Walker W, Cooley L, Flavell RA, Agaisse H, Fikrig E: Antivirulence properties of an antifreeze protein. Cell Rep. 2014 Oct 23; 2014 Oct 16. PMID: 25373896
- Hudson AM, Cooley L: Methods for studying oogenesis. Methods. 2014 Jun 15; 2014 Jan 17. PMID: 24440745
- Yan D, Neumüller RA, Buckner M, Ayers K, Li H, Hu Y, Yang-Zhou D, Pan L, Wang X, Kelley C, Vinayagam A, Binari R, Randklev S, Perkins LA, Xie T, Cooley L, Perrimon N: A regulatory network of Drosophila germline stem cell self-renewal. Dev Cell. 2014 Feb 24. PMID: 24576427
- McLean PF, Cooley L: Bridging the divide: illuminating the path of intercellular exchange through ring canals. Fly (Austin). 2014; 2013 Nov 8. PMID: 24406334
- Hartwich TM, Subach FV, Cooley L, Verkhusha VV, Bewersdorf J: Determination of two-photon photoactivation rates of fluorescent proteins. Phys Chem Chem Phys. 2013 Sep 28. PMID: 23852136
- McLean PF, Cooley L: Protein equilibration through somatic ring canals in Drosophila. Science. 2013 Jun 21; 2013 May 23. PMID: 23704373
- Neelakanta G, Hudson AM, Sultana H, Cooley L, Fikrig E: Expression of Ixodes scapularis antifreeze glycoprotein enhances cold tolerance in Drosophila melanogaster. PLoS One. 2012; 2012 Mar 13. PMID: 22428051
- Airoldi SJ, McLean PF, Shimada Y, Cooley L: Intercellular protein movement in syncytial Drosophila follicle cells. J Cell Sci. 2011 Dec 1; 2011 Dec 1. PMID: 22135360
- Shimada Y, Burn KM, Niwa R, Cooley L: Reversible response of protein localization and microtubule organization to nutrient stress during Drosophila early oogenesis. Dev Biol. 2011 Jul 15; 2011 Apr 23. PMID: 21570389
- Hudson AM, Cooley L: Drosophila Kelch functions with Cullin-3 to organize the ring canal actin cytoskeleton. J Cell Biol. 2010 Jan 11. PMID: 20065088
- Hudson AM, Petrella LN, Tanaka AJ, Cooley L: Mononuclear muscle cells in Drosophila ovaries revealed by GFP protein traps. Dev Biol. 2008 Feb 15; 2007 Dec 4. PMID: 18199432
- Hudson AM, Cooley L: Phylogenetic, structural and functional relationships between WD- and Kelch-repeat proteins. Subcell Biochem. 2008. PMID: 18925367
- Lee S, Cooley L: Jagunal is required for reorganizing the endoplasmic reticulum during Drosophila oogenesis. J Cell Biol. 2007 Mar 26. PMID: 17389229
- Quiñones-Coello AT, Petrella LN, Ayers K, Melillo A, Mazzalupo S, Hudson AM, Wang S, Castiblanco C, Buszczak M, Hoskins RA, Cooley L: Exploring strategies for protein trapping in Drosophila. Genetics. 2007 Mar; 2006 Dec 18. PMID: 17179094
- Petrella LN, Smith-Leiker T, Cooley L: The Ovhts polyprotein is cleaved to produce fusome and ring canal proteins required for Drosophila oogenesis. Development. 2007 Feb; 2007 Jan 10. PMID: 17215303
- Mermall V, Bonafé N, Jones L, Sellers JR, Cooley L, Mooseker MS: Drosophila myosin V is required for larval development and spermatid individualization. Dev Biol. 2005 Oct 1. PMID: 16126191
- Sokol NS, Cooley L: Drosophila filamin is required for follicle cell motility during oogenesis. Dev Biol. 2003 Aug 1. PMID: 12885568
- Buszczak M, Lu X, Segraves WA, Chang TY, Cooley L: Mutations in the midway gene disrupt a Drosophila acyl coenzyme A: diacylglycerol acyltransferase. Genetics. 2002 Apr. PMID: 11973306
- Mihaylov IS, Kondo T, Jones L, Ryzhikov S, Tanaka J, Zheng J, Higa LA, Minamino N, Cooley L, Zhang H: Control of DNA replication and chromosome ploidy by geminin and cyclin A. Mol Cell Biol. 2002 Mar. PMID: 11865064
- Kelso RJ, Hudson AM, Cooley L: Drosophila Kelch regulates actin organization via Src64-dependent tyrosine phosphorylation. J Cell Biol. 2002 Feb 18; 2002 Feb 18. PMID: 11854310
- Hudson AM, Cooley L: A subset of dynamic actin rearrangements in Drosophila requires the Arp2/3 complex. J Cell Biol. 2002 Feb 18; 2002 Feb 18. PMID: 11854308
- Hudson AM, Cooley L: Understanding the function of actin-binding proteins through genetic analysis of Drosophila oogenesis. Annu Rev Genet. 2002; 2002 Jun 11. PMID: 12429700