Shining light on Drosophila oogenesis: Live imaging of egg development

Department of Biological Chemistry, Center for Cell Dynamics, Johns Hopkins School of Medicine, 855 North Wolfe Street, Baltimore, MD 21205, USA.
Current opinion in genetics & development (Impact Factor: 7.57). 09/2011; 21(5):612-9. DOI: 10.1016/j.gde.2011.08.011
Source: PubMed

ABSTRACT Drosophila oogenesis is a powerful model for the study of numerous questions in cell and developmental biology. In addition to its longstanding value as a genetically tractable model of organogenesis, recently it has emerged as an excellent system in which to combine genetics and live imaging. Rapidly improving ex vivo culture conditions, new fluorescent biosensors and photo-manipulation tools, and advances in microscopy have allowed direct observation in real time of processes such as stem cell self-renewal, collective cell migration, and polarized mRNA and protein transport. In addition, entirely new phenomena have been discovered, including revolution of the follicle within the basement membrane and oscillating assembly and disassembly of myosin on a polarized actin network, both of which contribute to elongating this tissue. This review focuses on recent advances in live-cell imaging techniques and the biological insights gleaned from live imaging of egg chamber development.

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Available from: Denise Montell, Apr 09, 2014
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    • "Furthermore, in adult females injected with 20-hydroxyecdysone, premature BC migration was detected in a few rare cases (Bai et al., 2000). To address the question of whether BC migration can be rescued in the egg chambers containing phm FL99 or phm FT59 whole epithelial homozygous mutant clones by supplying these egg chambers with 20-hydroxyecdysone, we took advantage of the improved culture conditions supporting ex vivo development of stage 9 egg chambers in combination with live imaging (Dorman et al., 2004; He et al., 2011; Prasad et al., 2007, 2011; Prasad and Montell, 2007). We introduced membrane-mCherry (Martin et al., 2010) to the phm FL99 or phm FT59 genetic background to visualize cell outlines and to analyze BC dynamics in the cultured egg chambers in the course of time-lapse live imaging. "
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    Developmental Biology 12/2013; 386(2). DOI:10.1016/j.ydbio.2013.12.013 · 3.55 Impact Factor
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    ABSTRACT: Wiskott-Aldrich Syndrome (WASP) family proteins participate in many cellular processes involving rearrangements of the actin cytoskeleton. To the date, four WASP subfamily members have been described in Drosophila: Wash, WASp, SCAR, and Whamy. Wash, WASp, and SCAR are essential during early Drosophila development where they function in orchestrating cytoplasmic events including membrane-cytoskeleton interactions. A mutant for Whamy has not yet been reported. We generated monoclonal antibodies that are specific to Drosophila Wash, WASp, SCAR, and Whamy, and use these to describe their spatial and temporal localization patterns. Consistent with the importance of WASP family proteins in flies, we find that Wash, WASp, SCAR, and Whamy are dynamically expressed throughout oogenesis and embryogenesis. For example, we find that Wash accumulates at the oocyte cortex. WASp is highly expressed in the PNS, while SCAR is the most abundantly expressed in the CNS. Whamy exhibits an asymmetric subcellular localization that overlaps with mitochondria and is highly expressed in muscle. All four WASP family members show specific expression patterns, some of which reflect their previously known roles and others revealing new potential functions. The monoclonal antibodies developed offer valuable new tools to investigate how WASP family proteins regulate actin cytoskeleton dynamics.
    Developmental Dynamics 03/2012; 241(3):608-26. DOI:10.1002/dvdy.23742 · 2.38 Impact Factor
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    ABSTRACT: The Drosophila oocyte has been established as a versatile system for investigating fundamental questions such as cytoskeletal function, cell organization, and organelle structure and function. The availability of various GFP-tagged proteins means that many cellular processes can be monitored in living cells over the course of minutes or hours, and using this technique, processes such as RNP transport, epithelial morphogenesis, and tissue remodeling have been described in great detail in Drosophila oocytes1,2. The ability to perform video imaging combined with a rich repertoire of mutants allows an enormous variety of genes and processes to be examined in incredible detail. One such example is the process of ooplasmic streaming, which initiates at mid-oogenesis3,4. This vigorous movement of cytoplasmic vesicles is microtubule and kinesin-dependent5 and provides a useful system for investigating cytoskeleton function at these stages. Here I present a protocol for time lapse imaging of living oocytes using virtually any confocal microscopy setup.
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