A Survey of 6,300 Genomic Fragments for cis-Regulatory Activity in the Imaginal Discs of Drosophila melanogaster

Abstract

6,334 fragments from the genome of Drosophila melanogaster were analyzed for their ability to drive expression of GAL4 reporter genes in the 3rd instar larval imaginal discs. 1,194 reporter genes drove expression in the eye, antenna, leg, wing, haltere, or genital imaginal discs. The patterns ranged from large regions to individual cells. About 75% of the active fragments drove expression in multiple discs; 20% were expressed in ventral, but not dorsal, discs (legs, genital, and antenna), while ~23% were expressed in dorsal, but not ventral discs (wing, haltere, and eye). Several patterns, for example within the leg chordotonal organ, appeared a surprisingly large number of times. Unbiased searches for DNA sequence motifs suggest candidate transcription factors that may regulate enhancers with shared activities. Together, these expression patterns provide a valuable resource to the community and offer a broad overview of how transcriptional regulatory information is distributed in the Drosophila genome.

Gain of cis -regulatory activities underlies novel domains of wingless gene expression in Drosophila

“…2 D and G). These results are consistent with a recent survey describing a large collection of imaginal disc enhancers of D. melanogaster (Flylight) (26). Because the Wnt6 expression pattern is mostly similar to that of wg (27), and the clustering of four Wnt genes is conserved in the Drosophila genus, the loci have been inferred to share regulatory elements (28).…”

Antero-posterior patterning of Drosophila ocelli requires an anti-repressor mechanism within the hh-pathway mediated by the Six3 gene Optix

“…However, we have not been able to detect Optix expression in the embryonic primordium of the eyeantennal disc, marked with the disc primordium marker ey-Z and using either an anti-Optix antiserum or the OptixNP2631-GAL4 line (not shown). We have also analyzed the expression of all available regulatory constructs associated with the Optix locus generated by the Janelia Project (Jory et al, 2012). Neither of the lines expressed in the eye disc showed overlapping expression with the embryonic eye primordium (not shown).…”

“…The UAS/GAL4 system (Brand and Perrimon, 1993) was used for most gain-and loss-of-function assays. We used oc2-GAL4 (Blanco et al, 2009), 86C11-GAL4 (Jory et al, 2012), hh-GAL4 (Tanimoto et al, 2000) and OptixNP2631-GAL4 (Hayashi et al, 2002) lines, all of which showed expression in different domains of the dorsal head during larval development. UAS lines used were: UAS-Arm S10 (UAS-Arm*) (Pai et al, 1997), UAS-Hh 6.1 , UAS-Optix S1 (26806, Bloomington Stock Center) and UAS-en (Guillen et al, 1995) for the ectopic expression experiments; and UAS-enRNAi and UAS-OptixRNAi (35697 and 31910, Bloomington Stock Center) for the knockdown inductions.…”

Rationally designed fluorogenic protease reporter visualizes spatiotemporal dynamics of apoptosis in vivo

“…iCasper can also be used to examine spatiotemporal dynamics of apoptosis in a number of diseases including cancer. Moreover, iCasper may be used to study apoptosis in cell-typespecific lineage tracing during normal and disease development when combined with the large number of recently developed GAL4 lines (30)(31)(32). iCasper will also be useful to dissect signaling networks that lead to apoptosis by high-throughput screening using cultured cells or small animals.…”

“…iCasper represents a useful tool for future studies examining molecular mechanisms of cancer, as well as lineage tracing of specific types of cells during normal and tumor development when combined with the large number of recently developed GAL4 lines (30)(31)(32).…”