Project description:Purpose: We isolated Drosophila midgut cells : Delta+ intestinal stem cells (ISCs), Su(H)+enteroblasts (EBs), Esg+ cells (ISC+EB), Myo1A+Enterocytes (ECs), Pros+Enteroendocrine cells (EEs) and How+Visceral muscle cells (VM) from whole midguts to identify stem cell specific genes and study cell type specificities of midgut cells. We also isolated all the cell types from the 5 major regions (R1-R5) of the Drosophila midgut to study differences in cells in different regions. Methods: 3-7 day old female flies were dissected. Flies with GFP/YFP marking different cell types (using the GAL4-UAS system) were used to separate cells of the midgut.The midguts were dissociated with Elastase and FACS sorted using FACS AriaIII. RNA was extracted, amplified and sequenced. Whole midgut samples were sequenced on Illumina GAIIX and regional cell populations were sequenced on HiSeq2000. Methods:Raw fastqc reads were mapped to the Drosophila genome (Drosophila_melanogaster.BDGP5.70.dna.toplevel.fa) using Tophat 2.0.9 at default (using boost_1_54_0, bowtie2-2.1.0, samtools-0.1.19). Methods: For differential expression analysis, DESeq (p-value adjustment 0.05 by method Benjamini-Hochberg) was used. The reads were normalized also to Reads per kilobase of transcript per million mapped reads (RPKM). Results: More than 50% of the genome is expressed in the adult midgut (FlyAtlas- Chintapalli et al., 2007), of these genes about 50% (2457) were differentially expressed (DE) between all 4 cell types (ISCs, EBs, ECs and EEs) atleast 2 folds with 95% confidence Results: 159 genes that were specifically enriched in ISCs, 509 genes were specifically repressed in ISCs Conclusions: Our study represents the first detailed analysis of Drosophila intestinal cell transcriptomes, with biologic replicates, generated by RNA-seq technology.Our data facilitates comparative investigations of expression profiles of cells and reveals novel stem cell genes. Further region specific profiling adds precision to the analysis of variances in the midgut regions. We identify transcriptional regulators and regional transcription factors which modulate the midgut physiology. The dataset will be a great resource for hypothesis generation, tool building and fine tuned studies on the Drosophila midgut. mRNA profiles of Drosophila intestinal cells from whole midguts and midgut regions were generated by Deep Sequencing. Whole midgut profiles were generated in triplicates (Illumina GAIIx, 72 bp read length) and regional cell type profiles were genrated in duplicates (HiSeq 2000, 50bp read length).

Project description:Abstract: RAS-like (RAL) GTPases function in Wnt signalling-dependent intestinal stem cell proliferation and regeneration. Whether RAL proteins work as canonical RAS effectors in the intestine, and the mechanisms of how they contribute to tumorigenesis remain unclear. Here, we show that RAL GTPases are necessary and sufficient to activate EGFR/MAPK signalling in the intestine. We identify non-canonical roles of RAL GTPases not as RAS effectors, but rather by acting upstream of RAS activation via induction of EGFR internalisation . Knocking down Drosophila RalA from intestinal stem and progenitor cells leads to increased levels of plasma membrane-associated EGFR and decreased MAPK pathway activation. Importantly, in addition to impacting stem cell proliferation and damage-induced intestinal regeneration, this function of RAL GTPases drives EGFR-dependent tumorigenic growth in the intestine and in human mammary epithelium. Altogether, our results reveal previously unrecognised cellular and molecular contexts where RAL GTPases become essential mediators of EGFR-driven tissue homeostasis and malignant transformation. Results: RalA is required within ISCs to induce midgut adult midgut regeneration following damage by oral infection with Erwinia carotovora carotovora 15 (Ecc15) (Johansson et al., 2019). To achieve a global view of intestinal pathways affected by RalA, we performed a transcriptomic analysis by RNAseq of whole midguts from vehicle treated (Mock) or damaged (Ecc15 fed) control animals or following RalA knockdown in intestinal stem and progenitor cells using the escargot-gal4 driver (ISC/EB>) (Micchelli and Perrimon, 2006). Consistent with its effect on ISC proliferation (Johansson et al., 2019), RalA knockdown significantly impaired damage-induced upregulation of cell cycle genes in the midgut. Additionally, levels of multiple transcriptional targets of the EGFR/MAPK pathway (Golembo et al., 1996; Hsu et al., 2001; Jin et al., 2015; Meng and Biteau, 2015), such as argos (aos), rhomboid (rho), Sox21a and string (stg) were increased following Ecc15 infection in control midguts. The upregulation of these target genes was significantly impaired upon RalA knockdown.

Project description:Purpose: We isolated Drosophila midgut cells : Delta+ intestinal stem cells (ISCs), Su(H)+enteroblasts (EBs), Esg+ cells (ISC+EB), Myo1A+Enterocytes (ECs), Pros+Enteroendocrine cells (EEs) and How+Visceral muscle cells (VM) from whole midguts to identify stem cell specific genes and study cell type specificities of midgut cells. We also isolated all the cell types from the 5 major regions (R1-R5) of the Drosophila midgut to study differences in cells in different regions. Methods: 3-7 day old female flies were dissected. Flies with GFP/YFP marking different cell types (using the GAL4-UAS system) were used to separate cells of the midgut.The midguts were dissociated with Elastase and FACS sorted using FACS AriaIII. RNA was extracted, amplified and sequenced. Whole midgut samples were sequenced on Illumina GAIIX and regional cell populations were sequenced on HiSeq2000. Methods:Raw fastqc reads were mapped to the Drosophila genome (Drosophila_melanogaster.BDGP5.70.dna.toplevel.fa) using Tophat 2.0.9 at default (using boost_1_54_0, bowtie2-2.1.0, samtools-0.1.19). Methods: For differential expression analysis, DESeq (p-value adjustment 0.05 by method Benjamini-Hochberg) was used. The reads were normalized also to Reads per kilobase of transcript per million mapped reads (RPKM). Results: More than 50% of the genome is expressed in the adult midgut (FlyAtlas- Chintapalli et al., 2007), of these genes about 50% (2457) were differentially expressed (DE) between all 4 cell types (ISCs, EBs, ECs and EEs) atleast 2 folds with 95% confidence Results: 159 genes that were specifically enriched in ISCs, 509 genes were specifically repressed in ISCs Conclusions: Our study represents the first detailed analysis of Drosophila intestinal cell transcriptomes, with biologic replicates, generated by RNA-seq technology.Our data facilitates comparative investigations of expression profiles of cells and reveals novel stem cell genes. Further region specific profiling adds precision to the analysis of variances in the midgut regions. We identify transcriptional regulators and regional transcription factors which modulate the midgut physiology. The dataset will be a great resource for hypothesis generation, tool building and fine tuned studies on the Drosophila midgut.

Dataset Information

MicroRNA-mediated control of Drosophila midgut regeneration [miRNA]

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure