Expression pattern of dd4, a sole member of the d4 family of transcription factors in Drosophila melanogaster

Abstract Feeding is an essential part of animal life that is greatly impacted by the sense of taste. Although the characterization of taste-detection at the periphery has been extensive, higher order taste and feeding circuits are still being elucidated. Here, we use an automated closed-loop optogenetic activation screen to detect novel taste and feeding neurons in Drosophila melanogaster. Out of 122 Janelia FlyLight Project GAL4 lines preselected based on expression pattern, we identify six lines that acutely promote feeding and 35 lines that inhibit it. As proof of principle, we follow up on R70C07-GAL4, which labels neurons that strongly inhibit feeding. Using split-GAL4 lines to isolate subsets of the R70C07-GAL4 population, we find both appetitive and aversive neurons. Furthermore, we show that R70C07-GAL4 labels putative second-order taste interneurons that contact both sweet and bitter sensory neurons. These results serve as a resource for further functional dissection of fly feeding circuits.

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A silencer repressing redundant enhancer activities revealed by deleting endogenouscis-regulatory element ofebonyinDrosophila melanogaster

10.1101/2021.03.25.436947 ◽

2021 ◽

Author(s):

Noriyoshi Akiyama ◽

Shoma Sato ◽

Kentaro M. Tanaka ◽

Takaomi Sakai ◽

Aya Takahashi

Keyword(s):

Drosophila Melanogaster ◽

Genome Editing ◽

Expression Pattern ◽

Regulatory Region ◽

Regulatory Elements ◽

Biosynthesis Pathway ◽

Melanin Biosynthesis ◽

Pigment Synthesis ◽

Endogenous Expression ◽

Spatiotemporal Regulation

AbstractThe spatiotemporal regulation of gene expression is essential to ensure robust phenotypic outcomes. Pigmentation patterns inDrosophilaare formed by the deposition of different pigments synthesized in the developing epidermis and the role ofcis-regulatory elements (CREs) of melanin biosynthesis pathway-related genes is well-characterized. These CREs typically exhibit modular arrangement in the regulatory region of the gene with each enhancer regulating a specific spatiotemporal expression of the gene. However, recent studies have suggested that multiple enhancers of a number of developmental genes as well as those ofyellow(involved in dark pigment synthesis) exhibit redundant activities. Here we report the redundant enhancer activities in thecis-regulatory region of another gene in the melanin biosynthesis pathway,ebony, in the developing epidermis ofDrosophila melanogaster. The evidence was obtained by introducing an approximately 1 kbp deletion at the endogenous primary epidermis enhancer (priEE) by genome editing. The effect of the priEE deletion on pigmentation and on the endogenous expression pattern of amCherry-taggedebonyallele was examined in the thoracic and abdominal segments. The expression level ofebonyin the priEE-deleted strains was similar to that of the control strain, indicating the presence of redundant enhancer activities that drive the broad expression ofebonyin the developing epidermis. Additionally, the priEE fragment contained a silencer that suppressesebonyexpression in the dorsal midline of the abdominal tergites, which is necessary for the development of the subgenusSophophora-specific dark pigmentation patterns along the midline. The endogenous expression pattern ofebonyin the priEE-deleted strains and the reporter assay examining the autonomous activity of the priEE fragment indicated that the silencer is involved in repressing the activities of both proximal and distant enhancers. These results suggest that multiple silencers are dispensable in the regulatory system of a relatively stable taxonomic character. The prevalence of other redundant enhancers and silencers in the genome can be investigated using a similar approach.Author summaryGenes are expressed at the right timing and place to give rise to diverse phenotypes. The spatiotemporal regulation is usually achieved through the coordinated activities of transcription-activating and transcription-repressing proteins that bind to the DNA sequences called enhancers and silencers, respectively, located near the target gene. Most studies identified the locations of enhancers by examining the ability of the sequence fragments to regulate the expression of fused reporters. Various short enhancers have been identified using this approach. This study employed an alternative approach in which the previously identified enhancer that regulates expression ofebony(a gene involved in body color formation) was deleted in a fruitfly,Drosophila melanogaster, using the genome-editing technique. The knockout of this enhancer did not affect the transcription level of the gene to a large extent. This indicated the presence of transcription-activating elements with redundant functions outside the deleted enhancer. Additionally, the transcription ofebonyat the midline of the abdomen, which is repressed in the normal flies, were derepressed in the enhancer-deleted flies, which indicated that the deleted enhancer fragment contained a silencer that negatively regulates multiple enhancer activities in a spatially restricted manner.

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An Atlas of Transcription Factors Expressed in Male Pupal Terminalia of Drosophila melanogaster

G3 Genes|Genome|Genetics ◽

10.1534/g3.119.400788 ◽

2019 ◽

Vol 9 (12) ◽

pp. 3961-3972 ◽

Cited By ~ 4

Author(s):

Ben J. Vincent ◽

Gavin R. Rice ◽

Gabriella M. Wong ◽

William J. Glassford ◽

Kayla I. Downs ◽

...

Keyword(s):

Drosophila Melanogaster ◽

Transcription Factors

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Optimized Position Weight Matrices in Prediction of Novel Putative Binding Sites for Transcription Factors in the Drosophila melanogaster Genome

PLoS ONE ◽

10.1371/journal.pone.0068712 ◽

2013 ◽

Vol 8 (8) ◽

pp. e68712

Author(s):

Vyacheslav Y. Morozov ◽

Ilya P. Ioshikhes

Keyword(s):

Drosophila Melanogaster ◽

Transcription Factors ◽

Binding Sites

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HP1a, Su(var)3-9, SETDB1 and POF stimulate or repress gene expression depending on genomic position, gene length and expression pattern in Drosophila melanogaster

Nucleic Acids Research ◽

10.1093/nar/gkt158 ◽

2013 ◽

Vol 41 (8) ◽

pp. 4481-4494 ◽

Cited By ~ 28

Author(s):

Lina E. Lundberg ◽

Per Stenberg ◽

Jan Larsson

Keyword(s):

Gene Expression ◽

Drosophila Melanogaster ◽

Expression Pattern ◽

Gene Length ◽

Genomic Position

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178 Cellular and extracellular expression of stress response transcription factors in male and female bovine pre-implantation embryos under oxidative stress conditions

Reproduction Fertility and Development ◽

10.1071/rdv31n1ab178 ◽

2019 ◽

Vol 31 (1) ◽

pp. 213

Author(s):

M. O. Taqi ◽

S. Gebremedhn ◽

D. Salilew-Wondim ◽

F. Rings ◽

C. Neuhoff ◽

...

Keyword(s):

Oxidative Stress ◽

Transcription Factors ◽

Stress Response ◽

Cell Count ◽

Expression Pattern ◽

Total Cell ◽

Expression Level ◽

Total Cell Count ◽

Oxygen Level ◽

Male And Female

Pre-implantation embryo development is a critical stage, in which several development and stress-response related transcription factors (TF) are involved. Exposing embryos to environmental insults alter some of these stress response-related TF. However, their expression pattern in male and female embryos and their release via exosomes is still unclear. Here, we aimed to investigate the effect of culture-induced oxidative stress on development and expression pattern of stress-related TF in male and female embryos and in respective spent media coupled with exosomes. For this, bovine male and female zygotes were in vitro produced using sexed semen and cultured under 5% and 20% oxygen in exosome-depleted SOFaa medium (SOF with amino acids). Blastocysts were subjected to total RNA isolation followed by quantitative RT-PCR analysis of the selected TF (Nrf2, KLF4, NOTCH1, SREBF2, E2F1, CAT1, SOD1, and OCT4), as well as protein abundance analysis using immunofluorescence and related phenotypes analysis, including reactive oxygen species (ROS) level and total cell count. Furthermore, the spent embryo culture media were collected for exosomes isolation and expression analysis of candidate TF. The data were statistically analysed using one-way ANOVA followed by multiple pair-wise comparisons using the Tukey post hoc test. Results showed that the blastocyst rates of both male (29.9% v. 34.9%) and female (16.7% v. 26.5%) bovine embryos were significantly lower in 20% than in 5% oxygen level. Female blastocysts subjected to the higher oxygen level showed increased ROS level (37.66±1.70v. 45.32±2.05 in male and 29.42±1.44v. 45.51±2.06 in female) and significantly reduced total cell count compared with the male embryo counterpart (136.55±7.8v. 112.75±2.9 in male and 138.75±2.0v. 88.25±4.3 in female cultured in 5% and 20% oxygen levels, respectively). Consequently, the expression levels of Nrf2, KLF4, SREBF2, CAT1, SOD1, and OCT4 were significantly increased in male embryos exposed to oxidative stress compared with those cultured under the lower oxygen level. However, NOTCH1 and E2F1 were significantly increased in female embryos exposed to oxidative stress compared with the male counterparts. The mRNA level of SREBF2 was significantly increased in male embryos cultured under both 5% and 20% O2 compared with female embryos. The protein expression level of Nrf2 and KLF4 was higher in embryos cultured at 20% v. 5% O2 with greater Nrf2 abundance in male embryos. Consequently, the male embryos produced at 20% O2 released a higher number of exosomes enriched with Nrf2, SOD1, and NOTCH1 mRNA than the other groups. Interestingly, the exosomal mRNA expression level of E2F1 tended to be higher in female embryos exposed to oxidative stress than their male counterparts. Taken together, the male embryos were more tolerant to oxidative stress than female embryos via the activation Nrf2-mediated oxidative stress response and development related TF. The release of these TF via exosomes could enhance cellular homeostasis maintenance under oxidative stress.

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