Live Imaging of mRNA Transcription in Drosophila Embryos

Metazoan genes are embedded in a rich milieu of regulatory information that often includes multiple enhancers possessing overlapping activities. In this study, we employ quantitative live imaging methods to assess the function of pairs of primary and shadow enhancers in the regulation of key patterning genes-knirps, hunchback, and snail-in developing Drosophila embryos. The knirps enhancers exhibit additive, sometimes even super-additive activities, consistent with classical gene fusion studies. In contrast, the hunchback enhancers function sub-additively in anterior regions containing saturating levels of the Bicoid activator, but function additively in regions where there are diminishing levels of the Bicoid gradient. Strikingly sub-additive behavior is also observed for snail, whereby removal of the proximal enhancer causes a significant increase in gene expression. Quantitative modeling of enhancer–promoter interactions suggests that weakly active enhancers function additively while strong enhancers behave sub-additively due to competition with the target promoter.

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Live Imaging of Epithelial-Mesenchymal Transition in Mesoderm Cells of Gastrulating Drosophila Embryos

Methods in Molecular Biology - The Epithelial-to Mesenchymal Transition ◽

10.1007/978-1-0716-0779-4_8 ◽

2020 ◽

pp. 65-77

Author(s):

Lingkun Gu ◽

Mo Weng

Keyword(s):

Epithelial Mesenchymal Transition ◽

Live Imaging ◽

Mesenchymal Transition ◽

Drosophila Embryos

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Using RNA Tags for Multicolor Live Imaging of Chromatin Loci and Transcription in Drosophila Embryos

Methods in Molecular Biology - RNA Tagging ◽

10.1007/978-1-0716-0712-1_22 ◽

2020 ◽

pp. 373-384

Author(s):

Hongtao Chen ◽

Thomas Gregor

Keyword(s):

Live Imaging ◽

Drosophila Embryos

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Live Imaging of Drosophila Embryos: Quantifying Protein Numbers and Dynamics at Subcellular Locations

Methods in Molecular Biology - Planar Cell Polarity ◽

10.1007/978-1-61779-510-7_1 ◽

2011 ◽

pp. 1-17 ◽

Cited By ~ 5

Author(s):

Daryl J. V. David ◽

Melanie A. McGill ◽

R. F. Andrew McKinley ◽

Tony J. C. Harris

Keyword(s):

Live Imaging ◽

Drosophila Embryos

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Detection and mapping of interactions between chromatin and the nuclear envelope in drosophila embryos

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100140191 ◽

1995 ◽

Vol 53 ◽

pp. 764-765

Author(s):

W.F. Marshall ◽

A.F. Dernburg ◽

B. Harmon ◽

J.W. Sedat

Keyword(s):

Nuclear Envelope ◽

Chromatin Condensation ◽

Three Dimensional ◽

Physiological Role ◽

Nuclear Surface ◽

Intact Cells ◽

Molecular Determinants ◽

Surface Harmonic ◽

Drosophila Embryos

Interactions between chromatin and nuclear envelope (NE) have been implicated in chromatin condensation, gene regulation, nuclear reassembly, and organization of chromosomes within the nucleus. To further investigate the physiological role played by such interactions, it will be necessary to determine which loci specifically interact with the nuclear envelope. This will not only facilitate identification of the molecular determinants of this interaction, but will also allow manipulation of the pattern of chromatin-NE interactions to probe possible functions. We have developed a microscopic approach to detect and map chromatin-NE interactions inside intact cells.Fluorescence in situ hybridization (FISH) is used to localize specific chromosomal regions within the nucleus of Drosophila embryos and anti-lamin immunofluorescence is used to detect the nuclear envelope. Widefield deconvolution microscopy is then used to obtain a three-dimensional image of the sample (Fig. 1). The nuclear surface is represented by a surface-harmonic expansion (Fig 2). A statistical test for association of the FISH spot with the surface is then performed.

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Laser scanning confocal microscopic analysis of cytoskeletal and nuclear reorganization in live Drosophila embryos

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100146710 ◽

1993 ◽

Vol 51 ◽

pp. 174-175

Author(s):

William Theurkauf

Keyword(s):

Laser Scanning ◽

Microscopic Analysis ◽

Large Cell ◽

Early Embryo ◽

Drosophila Embryo ◽

Cortical Actin ◽

Nuclear Reorganization ◽

Cytoskeletal Elements ◽

Microtubule Structure ◽

Drosophila Embryos

Cell division in eucaryotes depends on coordinated changes in nuclear and cytoskeletal components. In Drosophila melanogaster embryos, the first 13 nuclear divisions occur without cytokinesis. During the final four divisions, nuclei divide in a uniform monolayer at the surface of the embryo. These surface divisions are accompanied by dramatic changes in cortical actin and microtubule structure (Karr and Alberts, 1986), and inhibitor studies indicate that these changes are essential to orderly mitosis (Zalokar and Erk, 1976). Because the early embryo is syncytial, fluorescent probes introduced by microinjection are incorporated in structures associated with all of the nuclei in the blastoderm. In addition, the nuclei divide synchronously every 10 to 20 min. These characteristics make the syncytial blastoderm embryo an excellent system for the analysis of mitotic reorganization of both nuclear and cytoskeletal elements. However, the Drosophila embryo is a large cell, and resolution of cytoskeletal filaments and nuclear structure is hampered by out-of focus signal.

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