Mouse hair follicles undergo synchronized cycles. Cyclical regeneration and hair growth is fueled by stem cells (SCs). Following hair regeneration, SCs within the bulge and its vicinity (upper ORS which becomes the bulge for the next cycle) briefly self-renew to replenish expended SCs and ensure long-term tissue regeneration.
An RNA interference screen uncovers a new molecule in stem cell self-renewal and long-term regeneration.
Sex, Specimen part
View SamplesGenome-wide RNAi screens in mice identified Ctnnb1 and Mllt6 as physiological regulators of HrasG12V-dependent epidermal hyperplasia. To probe the consequences of Ctnnb1 and Mllt6 on HrasG12V-dependent oncogenic growth, we examined how their depletion impacts gene expression in the HrasoncoX2 epidermis. We performed RNA-seq analysis of FACS-purified embryonic epidermal cells, followed by network analysis of differentially regulated transcripts. Whether Ctnnb1 or Mllt6, knockdown markedly enhanced activity of genes restricting growth, and decreased expression of genes promoting epidermal proliferation. This contrasted with known transcriptional changes that typically follow epidermal expression of oncogenic Hras. Moreover, there was a significant overlap in genes whose expression was affected by Mllt6 and ß-catenin, further implying a level of shared function. Overall design: Transcriptional profiles of epidermal progenitors of embryonic day 18.5 animals of wild-type, HrasG12V, and HrasG12V depleted of Ctnnb1 or Mllt6 backgrounds.
RNAi screens in mice identify physiological regulators of oncogenic growth.
Cell line, Subject
View SamplesRegulation of neural stem cell (NSC) fate decisions is critical during the transition from a multicellular mammalian forebrain neuroepithelium to the multilayered neocortex. Forebrain development requires coordinated vascular investment alongside NSC differentiation. Vascular endothelial growth factor A (Vegf) has proven to be a pleiotrophic gene whose multiple protein isoforms regulate a broad range of effects in neurovascular systems. To test the hypothesis that the Vegf isoforms (120, 164, and 188) are required for normal forebrain development, we analyzed the forebrain transcriptome of mice expressing specific Vegf isoforms, Vegf120, VegfF188, or a combination of Vegf120/188. Transcriptome analysis identified differentially expressed genes in embryonic day (E) 9.5 forebrain, a time point preceding dramatic neuroepithelial expansion and vascular investment in the telencephalon. Meta-analysis identified gene pathways linked to chromosome-level modifications, cell fate regulation, and neurogenesis that were altered in Vegf isoform mice.
Shifts in the vascular endothelial growth factor isoforms result in transcriptome changes correlated with early neural stem cell proliferation and differentiation in mouse forebrain.
Specimen part
View SamplesThis work was designed to determine the role of the vascular endothelial growth factor A (VEGF) isoforms during early neuroepithelial development in the mammalian central nervous system (CNS), specifically in the forebrain. An emerging model of interdependence between neural and vascular systems includes VEGF, with its dual roles as a potent angiogenesis factor and neural regulator. Although a number of studies have implicated VEGF in CNS development, little is known about the role that the different VEGF isoforms play in early neurogenesis. We used a mouse model of disrupted VEGF isoform expression that eliminates the predominant brain isoform, VEGF164, and expresses only the diffusible form, VEGF120. We tested the hypothesis that VEGF164 plays a key role in controlling neural precursor populations in developing cortex. We used microarray analysis to compare gene expression differences between wild type and VEGF120 mice at E9.5, the primitive stem cell stage of the neuroepithelium. We quantified changes in PHH3-positive nuclei, neural stem cell markers (Pax6 and nestin) and the Tbr2-positive intermediate progenitors at E11.5 when the neural precursor population is expanding rapidly. Absence of VEGF164 (and VEGF188) leads to reduced proliferation without an apparent effect on the number of Tbr2-positive cells. There is a corresponding reduction in the number of mitotic spindles that are oriented parallel to the ventricular surface relative to those with a vertical or oblique angle. These results support a role for the VEGF isoforms in supporting the neural precursor population of the early neuroepithelium.
Vascular endothelial growth factor (VEGF) isoform regulation of early forebrain development.
Specimen part
View SamplesTargets of Retinoic Acid (RA) and 3,4-didehydroretinoic acid (ddRA) were identified in primary human epidermal keratinocytes grown in the presence of atRA or ddRA for 4 and 24 hours.
The effect of two endogenous retinoids on the mRNA expression profile in human primary keratinocytes, focusing on genes causing autosomal recessive congenital ichthyosis.
Treatment
View SamplesPurpose: using RNA-seq as a screening tool to determine candidate genes of interest within a genetically defined neural subpopulation in the zebrafish embryonic spinal cord. Results: The early embryonic spinal cord displays patterns of spontaneous activity that generate the earliest motor behavior in the zebrafish. We show the behavior and the neural activity to be inhibited by environmental levels of light. Since at these young ages the fish is blind, and since restricted illumination patterns on the trunk of the fish can elicit a photo-response, we hypothesized that the photo-inhibition is an intrinsic property of the active central pattern generator network within the spinal cord. We FACS-isolated cells from this network as well as those from a panneuronal population and sequenced mRNAs. Through differential expression analysis we identified vertebrate ancient long opsin a as a candidate and then further validated its function in the circuit through knockdown and rescue experiments. Overall design: RNA sequencing of 2 FACS purified neural populations from zebrafish spinal cord.
A spinal opsin controls early neural activity and drives a behavioral light response.
No sample metadata fields
View SamplesThe adaptor protein Lnk is an important negative regulator of HSC homeostasis and self-renewal. This study aims to investigate the role of Lnk in HSC aging. Here we performed expression profiling of bone marrow CD150+CD48-LSK LT-HSCs from young and old WT and Lnk-/- mice. Results identify select Lnk-mediated pathways with potential involvement in HSC self-renewal and aging.
Lnk deficiency partially mitigates hematopoietic stem cell aging.
Specimen part
View SamplesTHREE INDEPENDENT REPLICATES AND ARE THE CONTROL NON-INFECTED CELLS:
Modulation of NB4 promyelocytic leukemic cell machinery by Anaplasma phagocytophilum.
No sample metadata fields
View SamplesRecessive retinitis pigmentosa (RP) is often caused by nonsense mutations that lead to low mRNA levels as a result of nonsense-mediated decay. Some RP genes are expressed at detectable levels in leukocytes as well as in the retina. We designed a microarray-based method to find recessive RP genes based on low lymphoblast mRNA expression levels
Insights from retinitis pigmentosa into the roles of isocitrate dehydrogenases in the Krebs cycle.
No sample metadata fields
View SamplesA key requisite for the success of a dendritic cell (DC)-based vaccine in treating malignancies is the capacity of the DCs to attract immune effector cells for further interaction and activation, considering crosstalk with DCs is partially regulated by cell-contact-dependent mechanisms. Although critical for therapeutic efficacy, immune cell recruitment is a largely overlooked aspect regarding optimization of DC therapy. In this paper we examine if the so-called interleukin (IL)-15 DC vaccine provides a favorable chemokine milieu for recruiting T cells, natural killer (NK) cells and gamma delta () T cells, in comparison with the IL-4 DCs used routinely for clinical studies, as well as the underlying mechanisms of immune cell attraction by IL-15 DCs. Chemokine signaling is studied both at the RNA level, using microarray data of mature DCs, and functional level, by means of a transwell chemotaxis assay. Important to note, the classic IL-4 DC vaccine falls short to attract the required immune effector lymphocytes, whereas the IL-15 DCs provide a favorable chemokine milieu for recruiting all cytolytic effector cells. The elevated secretion of the chemokine (C-C motif) ligand 4 (CCL4), also known as macrophage inflammatory protein-1 (MIP-1), by IL-15 DCs underlies the enhanced migratory responsiveness of T cells, NK cells and T cells. Namely, neutralizing its receptor CCR5 resulted in a significant drop in migration of the aforementioned effector cells towards IL-15 DCs. These findings should be kept in mind in the design of future DC-based cancer vaccines.
Desirable cytolytic immune effector cell recruitment by interleukin-15 dendritic cells.
Specimen part, Subject
View Samples