Increasing evidence suggests that Long non-coding RNAs (LncRNAs) represent a new class of regulators of stem cells. However, the roles of LncRNAs in stem cell maintenance and myogenesis remain largely unexamined. For this study, hundreds of novel intergenic LncRNAs were identified that are expressed in myoblasts and regulated during differentiation. One of these LncRNAs, termed LncMyoD, is encoded next to the Myod gene and is directly activated by MyoD during myoblast differentiation. Knockdown of LncMyoD strongly inhibits terminal muscle differentiation largely due to a failure to exit the cell cycle. LncMyoD directly binds to IGF2-mRNA-binding-protein 2 (IMP2) and negatively regulates IMP2-mediated translation of proliferation genes such as N-Ras and c-Myc. While the RNA sequence of LncMyoD is not well-conserved between human and mouse, its locus, gene structure and function is preserved. The MyoD-LncMyoD-IMP2 pathway elucidates a mechanism as to how MyoD blocks proliferation to create a permissive state for differentiation.
A long non-coding RNA, LncMyoD, regulates skeletal muscle differentiation by blocking IMP2-mediated mRNA translation.
Age
View SamplesWe sought to identify critical factors regulating muscle stem cell activation and commitment, and determined through loss-of-function analyses that HMGA2 (high mobility group AT-hook 2) is a key regulator of myogenesis both in vitro and in vivo.
An HMGA2-IGF2BP2 axis regulates myoblast proliferation and myogenesis.
Sex, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Cross-species transcriptional network analysis defines shared inflammatory responses in murine and human lupus nephritis.
Specimen part, Disease, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Cross-species transcriptional network analysis defines shared inflammatory responses in murine and human lupus nephritis.
Specimen part
View SamplesNephritis (LN) is a serious manifestation of SLE. Therapeutic studies in mouse LN models do not always predict outcomes of human therapeutic trials, raising concerns about the human relevance of these models. In this study we used an unbiased transcriptional network approach to define similarities and differences between three lupus models and human LN. Affymetrix-based expression profiles were analyzed using Genomatix Bibliosphere software and transcriptional networks were compared using the Tool for Approximate LargE graph matching (TALE). The 20 network hubs (nodes) shared between all three models and human LN reflect key pathologic processes, namely immune cell infiltration/activation, macrophage/dendritic cell activation, endothelial cell activation/injury and tissue remodeling/fibrosis. Each model also shares unique features with human LN. Pathway analysis of the TALE nodes highlighted macrophage/DC activation as a cross-species shared feature. To distinguish which genes and activation pathways might derive from mononuclear phagocytes in the human kidneys the gene expression profile of isolated NZB/W renal mononuclear cells was compared with human LN kidney profiles. Network analysis of the shared signature highlighted NFkappaB1 and PPARgamma as major hubs in the tubulointerstitial and glomerular networks respectively. Key nodes in the renal macrophage inflammatory response form the basis for further mechanistic and therapeutic studies.
Cross-species transcriptional network analysis defines shared inflammatory responses in murine and human lupus nephritis.
Specimen part, Disease, Subject
View SamplesExpression data from human with hypertensive nephropathy (HT)
Cross-species transcriptional network analysis defines shared inflammatory responses in murine and human lupus nephritis.
Specimen part
View SamplesPolyinosinic:polycytidylic acid (poly I:C) is a synthetic analogue of double-stranded (ds)RNA, a molecular pattern associated with viral infections, that is used to exacerbate inflammation in lung injury models. Despite its frequent use, there are no detailed studies of the responses elicited by a single topical administration of poly I:C to the lungs of mice. Our data provides the first demonstration that the molecular responses in the airways induced by poly I:C correlate to those observed in the lungs of COPD patients. These expression data also revealed three distinct phases of response to poly I:C, consistent with the changing inflammatory cell infiltrate in the airways. Poly I:C induced increased numbers of neutrophils and NK cells in the airways, which were blocked by CXCR2 and CCR5 antagonists, respectively. Using gene set variation analysis on representative data sets, gene sets defined by poly I:C-induced DEGs were enriched in the molecular profiles of chronic obstructive pulmonary disease (COPD), but not idiopathic pulmonary fibrosis patients. Collectively, these data represent a new approach for validating the clinical relevance of preclinical animal models and demonstrate that a dual CXCR2/CCR5 antagonist may be an effective treatment for COPD patients.
Double-stranded RNA induces molecular and inflammatory signatures that are directly relevant to COPD.
Sex, Specimen part, Time
View SamplesBackground: The basic helix-loop-helix transcription factor TWIST1 (Twist) is involved in embryonic cell lineage determination and mesodermal differentiation. There is evidence to indicate that Twist expression plays a role in breast tumor formation and metastasis, but the role of Twist in dysregulating pathways that drive the metastatic cascade is unclear. Importantly, the genes and pathways dysregulated by Twist in cell lines and mouse models have not been validated against data obtained from patient samples.
Genomic pathways modulated by Twist in breast cancer.
Specimen part
View SamplesNon-switched memory (ME-M) B cells are an enigmatic population of IgM+ memory lymphocytes that are thought to emerge from germinal centers during systemic antibody responses against T cell-dependent antigens. To gain new insights into the properties of ME-M B cells generated during intestinal antibody responses, we performed global gene transcriptome expression analysis on nave, ME-M and canonical memory class-switched (ME-SW) B cells purified from human gut samples. Marginal zone (MZ) and ME-SW B cells isolated from human spleen samples were used for comparison.
Human Secretory IgM Emerges from Plasma Cells Clonally Related to Gut Memory B Cells and Targets Highly Diverse Commensals.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
LASP-1: a nuclear hub for the UHRF1-DNMT1-G9a-Snail1 complex.
Specimen part, Cell line
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