Mutations in the gene encoding laminin a2 chain cause congenital muscular dystrophy, MDC1A. In skeletal muscle, laminin a2 chain binds at least two receptor complexes; the dystrophin-glycoprotein complex and integrin a7b1. To gain insight into the molecular mechanisms underlying this disorder, we performed gene expression profiling of laminin a2 chain deficient mouse limb muscle. One of the down-regulated genes encodes a protein called calcium and integrin binding protein 2 (Cib2) whose expression and function is unknown. However, the closely related Cib1 has been reported to bind integrin aIIb and may be involved in outside-in-signaling in platelets. Since Cib2 might be a novel integrin a7b1 binding protein in muscle, we have studied Cib2 expression in the developing and adult mouse. Cib2 mRNA is mainly expressed in the developing central nervous system and in developing and adult skeletal muscle. In skeletal muscle Cib2 colocalizes with integrin a7B subunit at the sarcolemma and at the neuromuscular- and myotendinous junctions. Finally, we demonstrate that Cib2 is a calcium binding protein that interacts with integrin a7Bb1D. Thus, our data suggest a role for Cib2 as a cytoplasmic effector of integrin a7Bb1D signaling in skeletal muscle
Cib2 binds integrin alpha7Bbeta1D and is reduced in laminin alpha2 chain-deficient muscular dystrophy.
No sample metadata fields
View SamplesL-Arginine (L-Arg) is the substrate for both inducible nitric oxide synthase and arginase, which are upregulated in human IBD and in mouse colitis models. We have found that L-Arg supplementation enhances wound restitution in vitro, and improves the clinical parameters of weight loss, survival, and colon weight/length, in dextran sulfate sodium (DSS) induced murine colitis. Our aim was to further identify the potential mechanisms underlying the clinical benefit of L-Arg supplementation.
L-arginine supplementation improves responses to injury and inflammation in dextran sulfate sodium colitis.
Sex, Age, Specimen part
View SamplesExtrarenal viral infections commonly trigger glomerulonephritis mostly in association with immune complex disease. The immunoglobulin component of immune complexes can activate glomerular cell Fc receptors but whether complexed viral nucleic acids contribute to glomerular inflammation remains unknown. Glomerular mesangial cells express TLR3 but lack TLR7-9, hence, it is unclear whether mesangial cells can recognize and respond to viral ssRNA or DNA. Here we studied the immune responses activated by 3P-RNA (5'Triphosphate RNA) and Non-CpG DNA (Double stranded DNA) in primary mesangial cells (PMC).
Viral RNA and DNA trigger common antiviral responses in mesangial cells.
No sample metadata fields
View SamplesWe used Arabidopsis full-genome microarrays to characterize plant transcript accumulations at different stages of infection with the biotrophic oomycete downy mildew pathogen, Hyaloperonospora arabidopsidis : initiation (< 1 dpi) and maintenance of infection (> 4 dpi).
An Arabidopsis (malectin-like) leucine-rich repeat receptor-like kinase contributes to downy mildew disease.
Specimen part
View SamplesWe used Arabidopsis full-genome microarrays to characterize plant transcript accumulations in map65-3 and ugt76b1 mutants, 3 days after water treatment and inoculation with the biotrophic oomycete downy mildew pathogen, Hyaloperonospora arabidopsidis (Hpa)
The Arabidopsis microtubule-associated protein MAP65-3 supports infection by filamentous biotrophic pathogens by down-regulating salicylic acid-dependent defenses.
Specimen part, Time
View SamplesSustained Ca2+ entry into CD4+CD8+ double-positive thymocytes is required for positive selection. We identified a voltage-gated Na+ channel (VGSC), essential for positive selection of CD4+ T cells. Pharmacological inhibition of VGSC activity inhibited sustained Ca2+ influx induced by positive-selecting ligands and in vitro positive selection of CD4+ but not CD8+ T cells. In vivo shRNA knockdown of Scn5a specifically inhibited positive selection of CD4+ T cells. Ectopic expression of VGSC in peripheral AND CD4+ T cells bestowed the ability to respond to a positively selecting ligand, directly demonstrating VGSC expression was responsible for increased sensitivity. Thus active VGSCs in thymocytes provides a mechanism by which a weak positive selecting signal can induce sustained Ca2+ signals required for CD4+ T cell development.
A voltage-gated sodium channel is essential for the positive selection of CD4(+) T cells.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
ELF5 suppresses estrogen sensitivity and underpins the acquisition of antiestrogen resistance in luminal breast cancer.
Cell line, Treatment, Time
View SamplesMutations affecting the RAS-MAPK pathway frequently occur in relapse neuroblastoma tumors, which suggests that activation of this pathway is associated with a more aggressive phenotype. To explore this hypothesis we generated several model systems to define a neuroblastoma RAS-MAPK pathway signature. We could show that activation of this pathway in primary tumors indeed correlates with poor survival and is associated with known activating mutations in ALK and other RAS-MAPK pathway genes. From integrative analysis we could show that mutations in PHOX2B, CIC and DMD are also associated with an activated RAS-MAPK pathway. Mutation of PHOX2B and deletion of CIC in neuroblastoma cell lines induces activation of the RAS-MAPK pathway. This activation was independent of phosphorylated ERK in the CIC knock out systems. Furthermore, deletion of CIC causes a significant increase in tumor growth in vivo. These results show that the RAS-MAPK pathway is involved in tumor progression, and establish CIC as a powerful tumor suppressor that functions downstream of this pathway in neuroblastoma.
RAS-MAPK Pathway-Driven Tumor Progression Is Associated with Loss of CIC and Other Genomic Aberrations in Neuroblastoma.
Cell line
View SamplesInflorescence stages 1 to 12 from mutants involved in Arabidopsis small RNA metabolism. Three biological replicates of each mutant comprising at least 9 independent plants were harvested, and the expression profiles were determined using Affymetrix ATH1 arrays. Comparisons among the sample groups allow the identification of genes regulated by small RNAs (microRNAs and siRNAs).
microRNA-directed phasing during trans-acting siRNA biogenesis in plants.
No sample metadata fields
View SamplesT helper cell subsets have unique calcium (Ca2+) signals when activated with identical stimuli. The regulation of these Ca2+ signals and their correlation to the biological function of each T cell subset remains unclear. Trpm4 is a Ca2+-activated cation channel that we found is expressed at higher levels in Th2 cells compared to Th1 cells. Inhibition of Trpm4 expression increased Ca2+ influx and oscillatory levels in Th2 cells and decreased influx and oscillations in Th1 cells. This inhibition of Trpm4 expression also significantly altered T cell cytokine production and motility. Our experiments revealed that decreasing Trpm4 levels divergently regulates nuclear localization of NFAT. Consistent with this, gene profiling did not show Trpm4 dependent transcriptional regulation and T-bet and GATA-3 levels remain identical. Thus, Trpm4 is expressed at different levels on T helper cells and plays a distinctive role in T cell function by differentially regulating Ca2+ signaling and NFAT localization.
Trpm4 differentially regulates Th1 and Th2 function by altering calcium signaling and NFAT localization.
Specimen part, Treatment, Time
View Samples