The transcription factor Pax6 acts as a key developmental regulator in various organs. In the developing brain Pax6 regulates patterning, neurogenesis and proliferation, but how these diverse effects are mediated at the molecular level is not well understood. As Pax6 regulates forebrain development including neurogenesis, proliferation and patterning, almost exclusively by one of its DNA-binding domains, the bipartite paired domain, we examined the role of its respective DNA-binding subdomains (PAI and RED). Using mice with point mutations in the PAI (Pax6Leca4, N50K) and RED (Pax6Leca2, R128C) subdomains we unravelled opposing roles of mutations in these subdomains in regulating genes that control proliferation in the developing cerebral cortex.
Functional dissection of the paired domain of Pax6 reveals molecular mechanisms of coordinating neurogenesis and proliferation.
Sex
View SamplesThe activation of cellular quality control pathways to maintain metabolic homeostasis and mitigate diverse cellular stresses is emerging as a critical growth and survival mechanism in many cancers. Autophagy, a highly conserved cellular self-degradative process, is a key player in the initiation and maintenance of pancreatic ductal adenocarcinoma (PDA). However, the regulatory circuits that activate autophagy, and how they enable reprogramming of PDA cell metabolism are unknown. We now show that autophagy regulation in PDA occurs as part of a broader program that coordinates activation of lysosome biogenesis, function and nutrient scavenging, through constitutive activation of the MiT/TFE family of bHLH transcription factors. In PDA cells, the MiT/TFE proteins - MITF, TFE3 and TFEB - override a regulatory mechanism that controls their nuclear translocation, resulting in their constitutive activation. By orchestrating the expression of a coherent network of genes that induce high levels of lysosomal catabolic function, the MiT/TFE factors are required for proliferation and tumorigenicity of PDA cells. Importantly, unbiased global metabolite profiling reveals that MiT/TFE-dependent autophagy-lysosomal activation is specifically required to maintain intracellular AA pools in PDA. This AA flux is part of a program that is essential for metabolic homeostasis and bioenergetics of PDA but not for their non-transformed counterparts. These results identify the MiT/TFE transcription factors as master regulators of the autophagy-lysosomal system in PDA and demonstrate a central role of the autophagosome-lysosome compartment in maintaining tumor cell metabolism through alternative amino acid acquisition and utilization. Overall design: Examination of mRNA levels in pancreatic ductal adenocarcinoma (PDA) cell line 8988T after treatment with siRNA for control or TFE3
Transcriptional control of autophagy-lysosome function drives pancreatic cancer metabolism.
No sample metadata fields
View SamplesARC (NSC 188491, SMA-491), 4-amino-6-hydrazino-7-beta-d-ribofuranosyl-7H-pyrrolo-(2,3-d)-pyrimidine-5-carboxamide, is a nucleoside analog with profound in vitro anti-cancer activity. First identified in a high-throughput screen for inhibitors of p21 mRNA expression, subsequent experiments showed that ARC also repressed expression of hdm2 and survivin, leading to its classification as a global inhibitor of transcription 1. The following Hu U133 plus 2.0 arrays represent single time point (24 hour) gene expression analysis of transcripts altered by ARC treatment. Arrays for the other compounds (sangivamycin and doxorubicin) are included as comparators.
ARC (NSC 188491) has identical activity to Sangivamycin (NSC 65346) including inhibition of both P-TEFb and PKC.
No sample metadata fields
View SamplesDetermination of the molecular properties of genetically targeted cell types has led to fundamental insights into mouse brain function and dysfunction. Here, we report an efficient strategy for precise exploration of gene expression events in specific cell types in a broad range of species. We demonstrate that classically defined, homologous neuronal and glial cell types differ between rodent and human by the expression of hundreds of orthologous, cell specific genes. Confirmation that these genes are differentially active was obtained using epigenetic mapping, quantitative PCR, and immunofluorescence localization. Studies of sixteen human postmortem brains revealed cell-specific molecular responses to aging, and the induction of a shared, robust response to an unknown external event experienced by three donors. Our data establish a comprehensive approach for analysis of unique molecular events associated with specific circuits and cell types in a wide variety of human conditions. Overall design: RNA purified from nuclei or cytoplasm from mouse, rat, or human cerebellum. ATAC-seq was also performed using cerebellar nuclei from the three species.
Species and cell-type properties of classically defined human and rodent neurons and glia.
Sex, Age, Specimen part, Subject
View SamplesDetermination of the molecular properties of genetically targeted cell types has led to fundamental insights into mouse brain function and dysfunction. Here, we report an efficient strategy for precise exploration of gene expression events in specific cell types in a broad range of species. We demonstrate that classically defined, homologous neuronal and glial cell types differ between rodent and human by the expression of hundreds of orthologous, cell specific genes. Confirmation that these genes are differentially active was obtained using epigenetic mapping, quantitative PCR, and immunofluorescence localization. Studies of sixteen human postmortem brains revealed cell-specific molecular responses to aging, and the induction of a shared, robust response to an unknown external event experienced by three donors. Our data establish a comprehensive approach for analysis of unique molecular events associated with specific circuits and cell types in a wide variety of human conditions. Overall design: RNA purified from nuclei or cytoplasm from mouse, rat, or human cerebellum. ATAC-seq was also performed using cerebellar nuclei from the three species.
Species and cell-type properties of classically defined human and rodent neurons and glia.
Specimen part, Cell line, Subject
View SamplesBackground: In this study we reveal a previously undescribed role of the HACE1 (HECT domain and Ankyrin repeat Containing E3 ubiquitin-protein ligase 1) tumor suppressor protein in normal vertebrate heart development using the zebrafish (Danio rerio) model. We examined the link between the cardiac phenotypes associated with hace1 loss of function to the expression of the Rho small family GTPase, rac1, which is a known target of HACE1 and promotes ROS production via its interaction with NADPH oxidase holoenzymes. We examined expression changes induced by knock-down of hace1 in zebrafish at 48 hpf, the stage when heart abnormalities are observed. This was done by collecting duplicate samples of control and hace1 morphant embryos and performing RNA sequencing on them. Conclusions: Our study demonstrates that HACE1 is critical in the normal development and proper function of the heart via a ROS-dependent mechanism. Overall design: 2 samples of control and hace1 morphant zebrafish embryos at 48 hpf were analyzed
hace1 Influences zebrafish cardiac development via ROS-dependent mechanisms.
No sample metadata fields
View SamplesChronic non-healing venous leg ulcers (VLUs) are a widespread debilitating disease with high morbidity and associated costs, as approximately $15 billion annually are spent on the care of VLUs. Despite their socioeconomic burden, there is a paucity of novel treatments targeted towards healing VLUs, which can be attributed to both lack of pathophysiologic insight into VLU development as well as lack of knowledge regarding biologic actions of VLU-targeted therapies. Currently, the bioengineered bilayered living cellular construct (BLCC) skin substitute is the only FDA-approved biologic treatment for healing VLUs. To elucidate the mechanisms through which the BLCC promotes healing of chronic VLUs, we conducted a clinical trial (NCT01327937) in which patients with non-healing VLUs were treated with either standard care (compression therapy) or with BLCC together with standard care. Tissue was collected from the VLU edge before and 1 week after treatment, and samples underwent comprehensive microarray, mRNA and protein analyses. Ulcers treated with BLCC skin substitute displayed three distinct patterns suggesting the mechanisms by which BLCC shifted a non-healing into a healing tissue response: it modulated inflammatory and growth factor signaling; it activated keratinocytes; and it attenuated Wnt/-catenin signaling. In these ways, BLCC application orchestrated a shift of the chronic non-healing ulcer microenvironment into a distinctive healing milieu resembling that of an acute, healing wound. Our findings also provide first patient-derived in vivo evidence of specific biologic processes that can be targeted in the design of therapies to promote healing of chronic VLUs.
A bioengineered living cell construct activates an acute wound healing response in venous leg ulcers.
Specimen part, Disease stage, Time
View SamplesDiabetic foot ulcers (DFUs) are the leading cause of lower leg amputations in diabetic population. To better understand molecular pathophysiology of DFUs we used patients specimens and genomic profiling. We identified 3900 genes specifically regulated in DFUs. Moreover, we compared DFU to human skin acute wound (AW) profiles and found DNA repair mechanisms and regulation of gene expression among the processes specifically suppressed in DFUs, whereas essential wound healing-related processes, inflammatory/immune response or cell migration, were not activated properly. To identify potential regulators of DFU-specific genes, we used upstream target analysis. We found miR-15/16 family enriched in DFUs, but not in AW, which was confirmed by qPCR. We found that infection with the most common DFU colonizer, Staphylococcus aureus, triggers induction of miR-15-5p, which in turn, targets multiple DFU-specific genes, including genes involved in DNA repair (WEE1, MSH2 and RAD50) and the regulator of inflammatory pathway, IKBKB. Induction of miR-15b-5p, either by miR-mimic transfection in vitro or by S. aureus infection of acute wounds ex vivo, suppressed both WEE1 and IKBKB. Consequently, we detected an increase in DNA double strand breaks in DFUs. In summary, our data indicate that S. aureus infection, via induction of miR-15b-5p, may lead to suppression of DNA repair mechanisms and a sub-optimal inflammatory response, contributing to pathophysiology of DFU patients
Staphylococcus aureus Triggers Induction of miR-15B-5P to Diminish DNA Repair and Deregulate Inflammatory Response in Diabetic Foot Ulcers.
Specimen part, Disease, Disease stage
View SamplesPrimary human hepatocytes (PHHs) are a liver-specific cell subtype, and we have shown that these cells respond in a unique manner to the introduction of hepatitis C viral RNA (HCV vRNA) derived from different genotypes of the virus.
Transmitted/founder hepatitis C viruses induce cell-type- and genotype-specific differences in innate signaling within the liver.
Specimen part
View SamplesPurpose: Assess whether knocking out the UMLILO lncRNA altered the expression of genes transcribed within the CXCL chemokine TAD Outcome: To confirm whether the effect of UMLILO was limited to the CXCL TAD. Adeno-associated viral vectors (AAVs) were constructed that contain CRISPR/Cas9 and guides targeting UMLILO to delete the full length UMLILO transcript. RNAseq was performed on a transduced THP-1 population to verify genome-wide effects of UMLILO depletion. This revealed that IL8, CXCL1, 2, 3 transcription was abrogated, but a similar effect was not seen for genes located outside of the CXCL TAD boundary Overall design: AAVs were constructed that contain CRISPRs that harness non homologous end joining (NHEJ) to target UMLILO by deleting the genomic region encoding UMLILO, but not its promoter. The THP-1 monocytic cell line was transduced with the AAVs containing the CRISPRs for 1.5 weeks. Controls were transduced with AAV vector plasmids expressing SpCas9.
Immune genes are primed for robust transcription by proximal long noncoding RNAs located in nuclear compartments.
Specimen part, Subject
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