Project description:Purpose: To determine the effect of Lamin Dm0 expression on the transcription profile of ISCs/EBs with and without activated Jak/Stat signalling. Method: Lamin Dm0 and UPD were expressed in ISCs/EBs alone and in concert and the transcriptional changes compared with control flies. Conclusions: We found that 49% of UPD induced Jak/Stat targets were normalized by Lamin Dm0 coexpression.
Project description:The regulation of stem cell survival, self-renewal, and differentiation is critical for the maintenance of tissue homeostasis. Although the involvement of signaling pathways and transcriptional control mechanisms in stem cell regulation have been extensively investigated, the role of post-transcriptional control is still poorly understood. Here we show that the nuclear activity of the RNA-binding protein Second Mitotic Wave Missing (Swm) is critical for Drosophila melanogaster intestinal stem cells (ISCs) and their daughter cells, enteroblasts (EBs), to maintain their progenitor cell properties and function. Loss of swm causes ISCs and EBs to stop dividing and instead detach from the basement membrane, resulting in severe progenitor cell loss. swm loss is furthermore characterized by nuclear accumulation of poly(A)+ RNA in progenitor cells. Swm associates with transcripts involved in epithelial cell maintenance and adhesion, and the loss of swm, while not generally affecting the levels of these Swm-bound mRNAs, leads to elevated expression of proteins encoded by some of them, including the fly ortholog of Filamin. Taken together, this study indicates a nuclear role for Swm in adult stem cell maintenance, raising the possibility that nuclear post-transcriptional gene regulation plays vital roles in controlling adult stem cell maintenance and function.
Project description:Tissue stem cells divide asymmetrically to self-renew and generate differentiated progeny to maintain tissue homeostasis. Escargot (Esg) is a transcriptional repressor that is expressed in multiple stem cell populations in Drosophila melanogaster. Reduced esg function in intestinal stem cells (ISCs) causes a loss of ISCs and a biased differentiation of the daughter enteroblasts (EBs) toward the enteroendocrine (EE) cell fate. Loss of esg leads to an upregulation of differentiation factors and reduced Notch activity within EBs, indicating that Esg is a pivotal regulator of homeostasis in the intestine, supporting self-renewal to maintain a healthy stem cell pool as well as differentiation of progenitor cells. To identify potential transcriptional targets that mediate these phenotypes, in vivo DamID was used to generate the data deposited herein. 3 biological relicates were performed for Esg (with one dye-swap).
Project description:Shavenbaby (Svb) transcription factor is involved in the homeostasis of intestinal stem cells (ISCs), and the differentiation of their enteroblast progeny (EB) into enterocytes (EC). Svb is produced as a long repressor protein called SvbRepressor (SvbREP). In presence of Pri peptides SvbREP is processed into a shorter activator form (SvbACT) through partial proteasomal degradation of the REP domain. In ISCs/EBs, Pri triggers SvbREP to ACT maturation, while SvbREP form accumulates in differentiated enterocytes. The absence of Svb promote the apoptosis of the intestinal stem cells. In ISCs/EBs, the ectopic expression of SvbREP form promotes the differentiation and the overexpression of SvbACT promotes hyperplasia. (Al Hayek, et al 2020) Based on these functional analyses, Svb appears to control ISC/EB survival and behavior, balancing proliferation and differentiation through a molecular switch between its 2 antagonistic isoforms. In this study, we determine the Svb target genes in different cell types along the intestinal cell lineage. This particular metadata sheet refers to early enterocytes (mEC) transcriptomic data (RNAseq) in control condition and upon modulation of Svb function.
Project description:Shavenbaby (Svb) transcription factor is involved in the homeostasis of intestinal stem cells (ISCs), and the differentiation of their enteroblast progeny (EB) into enterocytes (EC). Svb is produced as a long repressor protein called SvbRepressor (SvbREP). In presence of Pri peptides SvbREP is processed into a shorter activator form (SvbACT) through partial proteasomal degradation of the REP domain. In ISCs/EBs, Pri triggers SvbREP to ACT maturation, while SvbREP form accumulates in differentiated enterocytes. The absence of Svb promote the apoptosis of the intestinal stem cells. In ISCs/EBs, the ectopic expression of SvbREP form promotes the differentiation and the overexpression of SvbACT promotes hyperplasia. (Al Hayek, et al 2020) Based on these functional analyses, Svb appears to control ISC/EB survival and behavior, balancing proliferation and differentiation through a molecular switch between its 2 antagonistic isoforms. In this study, we determine the Svb target genes in different cell types along the intestinal cell lineage. This particular metadata sheet refers to early enterocytes (eEC) transcriptomic data (RNAseq) in control condition and upon modulation of Svb function.
Project description:Shavenbaby (Svb) transcription factor is involved in the homeostasis of intestinal stem cells (ISCs), and the differentiation of their enteroblast progeny (EB) into enterocytes (EC). Svb is produced as a long repressor protein called SvbRepressor (SvbREP). In presence of Pri peptides SvbREP is processed into a shorter activator form (SvbACT) through partial proteasomal degradation of the REP domain. In ISCs/EBs, Pri triggers SvbREP to ACT maturation, while SvbREP form accumulates in differentiated enterocytes. The absence of Svb promote the apoptosis of the intestinal stem cells. In ISCs/EBs, the ectopic expression of SvbREP form promotes the differentiation and the overexpression of SvbACT promotes hyperplasia. (Al Hayek, et al 2020) Based on these functional analyses, Svb appears to control ISC/EB survival and behavior, balancing proliferation and differentiation through a molecular switch between its 2 antagonistic isoforms. In this study, we determine the Svb target genes in different cell types along the intestinal cell lineage. This particular metadata sheet refers to enteroblast (EB) transcriptomic data (RNAseq) in control condition and upon modulation of Svb function.
Project description:Tissue stem cells divide asymmetrically to self-renew and generate differentiated progeny to maintain tissue homeostasis. Escargot (Esg) is a transcriptional repressor that is expressed in multiple stem cell populations in Drosophila melanogaster. Reduced esg function in intestinal stem cells (ISCs) causes a loss of ISCs and a biased differentiation of the daughter enteroblasts (EBs) toward the enteroendocrine (EE) cell fate. Loss of esg leads to an upregulation of differentiation factors and reduced Notch activity within EBs, indicating that Esg is a pivotal regulator of homeostasis in the intestine, supporting self-renewal to maintain a healthy stem cell pool as well as differentiation of progenitor cells. To identify potential transcriptional targets that mediate these phenotypes, in vivo DamID was used to generate the data deposited herein.
Project description:We show direct conversion of mouse fibroblasts to cells that closely resemble intestinal stem cells (ISCs), through the state of fetal-type progenitor cells, called FIPCs. The induced ISCs (iISCs) exhibit self-renewal capacity and intestinal multi-lineage differentiation potential. Upon transplantation, iFIPCs and iISCs reconstitute colonic and intestinal epithelia, respectively.
Project description:Perturbed intestinal epithelial homeostasis demonstrated as decreased Lgr5+ intestinal stem cells (Lgr5 ISCs) and increased secretory lineages were observed in our study where Lkb1 was specfically deleted in Lgr5 ISCs using Lgr5-EGFP-creERT2 (Tamoxifen) deletor. To gain mechanistic insight how Lkb1 maintains intestinal epithelial stem cell homeostasis, Lkb1 deficient ISCs (Lgr5-high cells) and progenitors (Lgr5-low cells) are isolated by flow cytometry and profiled by RNA sequencing to compare with controls (Lkb1 wild type ISCs and progenitors).