Symptomatic glycerol kinase deficiency (GKD) is associated with episodic metabolic and central nervous system deterioration. We report here the first application of Weighted Gene Co-Expression Network Analysis (WGCNA) to investigate a knockout (KO) murine model of a human genetic disease. WGCNA identified networks and key hub transcripts from liver mRNA of glycerol kinase (Gyk) KO and wild type (WT) mice. Day of life 1 (dol1) samples from KO mice contained a network module enriched for organic acid metabolism before Gyk KO mice develop organic acidemia and die on dol3-4 and the module containing Gyk was enriched with apoptotic genes. Roles for the highly connected Acot, Psat and Plk3 transcripts were confirmed in cell cultures and subsequently validated by causality testing. We provide evidence that GK may have an apoptotic moonlighting role that is lost in GKD. This systems biology strategy has improved our understanding of GKD pathogenesis and suggests possible treatments.
Weighted gene co-expression network analysis identifies biomarkers in glycerol kinase deficient mice.
Sex, Specimen part
View SamplesWe used the Affymetrix GeneChip Mouse Genome 430 2.0 Arrays to compare the gene expression profiles of wildtype and miR-146a-deficient 2D2 transgenic T cells.
miR-146a modulates autoreactive Th17 cell differentiation and regulates organ-specific autoimmunity.
Specimen part
View SamplesPTEN loss or PI3K/AKT signaling pathway activation correlates with human prostate cancer progression and metastasis. However, in preclinical murine models, deletion of Pten alone fails to mimic the significant metastatic burden that frequently accompanies the end stage of human disease. To identify additional pathway alterations that cooperate with PTEN loss in prostate cancer progression, we surveyed human prostate cancer tissue microarrays and found that the RAS/MAPK pathway is significantly elevated both in primary and metastatic lesions. In an attempt to model this event, we crossed conditional activatable K-rasG12D/WT mice with the prostate conditional Pten deletion model we previously generated. Although RAS activation alone cannot initiate prostate cancer development, it significantly accelerated progression caused by PTEN loss, accompanied by epithelial-to-mesenchymal transition (EMT) and macrometastasis with 100% penitence. A novel stem/progenitor subpopulation with mesenchymal characteristics was isolated from the compound mutant prostates, which was highly metastatic upon orthotopic transplantation. Importantly, inhibition of RAS/MAPK signaling by PD325901, a MEK inhibitor, significantly reduced the metastatic progression initiated from transplanted stem/progenitor cells. Collectively, these data indicate that activation of RAS/MAPK signaling serves as a potentiating second hit to alteration of the PTEN/PI3K/AKT axis and co-targeting both pathways is highly effective in preventing the development of metastatic prostate cancers.
Pten loss and RAS/MAPK activation cooperate to promote EMT and metastasis initiated from prostate cancer stem/progenitor cells.
Specimen part
View SamplesActivation-Induced Cytidine Deaminase (AID) is required for somatic hypermutation and immunoglobulin (Ig) class switch recombination in germinal center B lymphocytes. Occasionally, AID targets non-Ig genes, thereby contributing to B cell lymphomagenesis. We recently reported aberrant expression of AID in BCR-ABL1-driven acute lymphoblastic leukemia (ALL). To elucidate the biological significance of aberrant AID expression, we studied loss of AID function in a murine model of BCR-ABL1 ALL. Mice transplanted with BCR-ABL1-transduced AID-/- bone marrow had prolonged survival as compared to mice transplanted with leukemia cells generated from AID+/+ bone marrow. Consistent with a causative role of AID in genetic instability, AID-/- leukemia had a decreased frequency of amplifications, deletions and a lower frequency of mutations in non-Ig genes including Pax5 and Rhoh as compared to AID+/+ leukemias. AID-/- and AID+/+ ALL cells showed a markedly distinct gene expression pattern as determined by principle component analysis, with 2,365 genes differentially expressed. In contrast to AID+/+ leukemia, AID-/- ALL cells failed to downregulate a number of tumor suppressor genes such as Rhoh, Cdkn1a (p21), and Blnk (SLP65). We conclude that AID accelerates clonal evolution in BCR-ABL1 ALL by enhancing genetic instability, aberrant somatic hypermutation, and by transcriptional inactivation of tumor suppressor genes.
No associated publication
Specimen part
View SamplesBone morphogenetic protein 4 (BMP4) is essential for lung development. To define its intracellular signaling mechanisms by which BMP4 regulates lung development, BMP-specific Smad1 or Smad5 was selectively knocked out in fetal mouse lung epithelial cells. Abrogation of lung epithelial-specific Smad1, but not Smad5, resulted in retardation of lung branching morphogenesis and reduced sacculation, accompanied by altered distal lung epithelial cell proliferation and differentiation, and consequently severe neonatal respiratory failure. By combining cDNA microarray with ChIP-chip analyses, Wnt inhibitory factor-1 (Wif1) was identified as a novel target gene of Smad1 in the developing mouse lung epithelial cells. Loss of Smad1 transcriptional activation of Wif1 expression was associated with reduced Wif1 expression and increased Wnt/beta-catenin signaling activity in lung epithelia, resulting in specific fetal lung abnormalities. Therefore, a novel regulatory loop of BMP4-Smad1-Wif1-Wnt/beta-catenin in coordinating BMP and Wnt pathways to control fetal lung development is suggested.
No associated publication
Specimen part
View SamplesMicroRNA regulates protein expression of cells by repressing translation of specific target messenger transcripts. Loss of the neuron specific microRNA miR-128 in Dopamine D1-receptor expressing neurons in the murine striatum (D1-MSNs) lead to increased neuronal excitability, locomotor hyperactivity and fatal epilepsy.
MicroRNA-128 governs neuronal excitability and motor behavior in mice.
No sample metadata fields
View SamplesCongenital malformations in facial bones significantly impact the overall representation of the face. Establishing correlations between gene expression and morphogenesis of craniofacial structures may lead to new discoveries of molecular mechanisms of craniofacial development. Thus in the present investigation, we will generate gene expression profiles of facial bones at embryo stage 14.5 to establish their roles in regulating craniofacial development.
No associated publication
Specimen part
View SamplesCongenital malformations in facial bones significantly impact the overall representation of face. Establishing a correlations between gene expression and morphogenesis of craniofacial structures may lead to new discoveries of molecular mechanisms of craniofacial development. Thus in the present investiation we will generate gene expression profile of different facial bones at different time intrevals over a period of 5 years to establish their roles in regulating craniofacial development
No associated publication
Specimen part
View SamplesTo characterize genes, pathways, and transcriptional regulators enriched in the mouse cornea, we compared the expression profiles of whole mouse cornea, bladder, esophagus, lung, proximal small intestine, skin, stomach, and trachea.
The Ets transcription factor EHF as a regulator of cornea epithelial cell identity.
Specimen part
View SamplesHair follicles undergo recurrent cycling of controlled growth (anagen), regression (catagen), and relative quiescence (telogen) with a defined periodicity. Taking a genomics approach to study gene expression during synchronized mouse hair follicle cycling, we discovered that, in addition to circadian fluctuation, CLOCK-regulated genes are also modulated in phase with the hair growth cycle. During telogen and early anagen, circadian clock genes are prominently expressed in the secondary hair germ, which contains precursor cells for the growing follicle. Analysis of Clock and Bmal1 mutant mice reveals a delay in anagen progression, and the secondary hair germ cells show decreased levels of phosphorylated Rb and lack mitotic cells, suggesting that circadian clock genes regulate anagen progression via their effect on the cell cycle. Consistent with a block at the G1 phase of the cell cycle, we show a significant upregulation of p21 in Bmal1 mutant skin. While circadian clock mechanisms have been implicated in a variety of diurnal biological processes, our findings indicate that circadian clock genes may be utilized to modulate the progression of non-diurnal cyclic processes.
Circadian clock genes contribute to the regulation of hair follicle cycling.
Sex
View Samples