Tools for neuroanatomy and neurogenetics in Drosophila. Proc Natl Acad Sci

Janelia Farm Research Campus, Howard Hughes Medical Institute, Ashburn VA 20147, USA.
Proceedings of the National Academy of Sciences (Impact Factor: 9.67). 07/2008; 105(28):9715-20. DOI: 10.1073/pnas.0803697105
Source: PubMed


We demonstrate the feasibility of generating thousands of transgenic Drosophila melanogaster lines in which the expression of an exogenous gene is reproducibly directed to distinct small subsets of cells in the adult brain. We expect the expression patterns produced by the collection of 5,000 lines that we are currently generating to encompass all neurons in the brain in a variety of intersecting patterns. Overlapping 3-kb DNA fragments from the flanking noncoding and intronic regions of genes thought to have patterned expression in the adult brain were inserted into a defined genomic location by site-specific recombination. These fragments were then assayed for their ability to function as transcriptional enhancers in conjunction with a synthetic core promoter designed to work with a wide variety of enhancer types. An analysis of 44 fragments from four genes found that >80% drive expression patterns in the brain; the observed patterns were, on average, comprised of <100 cells. Our results suggest that the D. melanogaster genome contains >50,000 enhancers and that multiple enhancers drive distinct subsets of expression of a gene in each tissue and developmental stage. We expect that these lines will be valuable tools for neuroanatomy as well as for the elucidation of neuronal circuits and information flow in the fly brain.

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    • "For a complete list of fly stocks see Supplemental Information. For EL-AD and CQ2-lexA, molecular constructs and transgenic flies were generated Neuron 88, 1–16, October 21, 2015 ª2015 Elsevier Inc. 13 Please cite this article in press as: Heckscher et al., Even-Skipped + Interneurons Are Core Components of a Sensorimotor Circuit that Maintains Left- Right Symmetric Muscle Contraction Amplitude, Neuron (2015), using standard methods as previously described (Pfeiffer et al., 2008, 2010). "
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    Neuron 10/2015; 88(2). DOI:10.1016/j.neuron.2015.09.009 · 15.05 Impact Factor
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    • "In the case of five out of eight of the identified enhancers, multiple constructs inserted in at least two distinct genomic locations were tested for activity. For the whole gene surveys, with the exception of upd, we used lines from the Rubin GAL4 collection (Jenett et al., 2012; Pfeiffer et al., 2008), in which non-coding sequences are fused to the GAL4 transcription factor and inserted into the attP2 site on the third chromosome. We supplemented these searches with constructs we generated (see Transgenic Constructs) when necessary. "
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    Developmental Cell 09/2015; DOI:10.1016/j.devcel.2015.08.005 · 9.71 Impact Factor
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    • "This system allows in vivo repurposing of gene expression patterns through genetic crossing schemes to switch between binary systems (Gal4, LexA, Q) or to achieve intersection by introducing Gal80 or Split-Gal4 hemi-drivers (Gohl et al. 2011) the minimal number of cells required for a behavior may be inhibited by the lack of enhancer-trap expression patterns with sufficiently restricted patterns to be informative for mapping. It may require the combination of a collection of enhancer-trap or promoter-driven Gal4 lines and ET-FLP lines to produce smaller intersection patterns (Pfeiffer et al. 2008; Jenett et al. 2012). Third, the number of ET-FLPx2 lines currently available most likely limits the power of the FINGR system. "
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    Journal of Comparative Physiology 04/2015; 201(9). DOI:10.1007/s00359-015-1010-y · 2.04 Impact Factor
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