The hypothesis is that genes involved in the immature schwann cell and promyelinating state will be upregulated and genes that are involved in the myelnating state will be down regulated.
MicroRNA-deficient Schwann cells display congenital hypomyelination.
Sex, Specimen part
View SamplesWe have generated mouse models of real CMT1B mutations in the gene encoding for myelin protein zero (P0). One of these mutants, P0S63del is retained in the ER where it elicits an unfolded protein response (UPR). Genetic ablation of the UPR factor CHOP restores the motor capacity in S63del mice. We used microarray to decipher the molecular mechanism undelying the P0S63del neuropathy and the rescue in S63del/Chop null nerves.
Resetting translational homeostasis restores myelination in Charcot-Marie-Tooth disease type 1B mice.
Age, Specimen part
View SamplesMyelination is essential for nervous system function. Schwann cells interact with neurons and with the basal lamina to sort and myelinate axons, using known receptors and signaling pathways. In contrast, the transcriptional control of axonal sorting and the role of mechano-transduction in myelination are largely unknown. Yap and Taz are effectors of the Hippo pathway that integrate chemical and mechanical signals in cells. Here, we describe a previously unknown role for the Hippo pathway in myelination. Using conditional mutagenesis in mice we show that Taz is required in Schwann cells for radial sorting and myelination. Yap is redundant with Taz as ablation of both Yap and Taz abolishes radial sorting. Yap/Taz regulate Schwann cell proliferation and transcription of basal lamina receptors, both necessary for proper radial sorting of axons, and subsequent myelination. These data link transcriptional effectors of the Hippo pathway and of mechanotransduction to myelin formation in Schwann cells. Overall design: 3 cKO and 3 control wild-type mice
YAP and TAZ control peripheral myelination and the expression of laminin receptors in Schwann cells.
Specimen part, Subject
View SamplesGDAP1 is a mitochondrial fission factor and mutations in GDAP1 cause Charcot-Marie-Tooth disease. Gdap1 knockout mice, mimicking genetic alterations of patients suffering from severe CMT forms, develop an age-related, hypomyelinating peripheral neuropathy.
The Gdap1 knockout mouse mechanistically links redox control to Charcot-Marie-Tooth disease.
Specimen part
View SamplesHippo signalling has been implicated as a key regulator of tissue regeneration. In the intestine, ex vivo organoid cultures model aspects of crypt epithelial regeneration. Therefore in order to uncover the Yap regulated transcriptional programs during crypt regeneration we performed RNA-sequencing of Yap wt and Yap deficient organoids, as well as organoids inducibly expressing Yap. Overall design: Yap loss of function organoids were harvested from Yapfl/fl;VillinCre mice (Yap-/-). In addition, we developed Yap overexpressing organoids by generating a doxycycline-inducible wild-type Yap transgenic line under the control of a Cre driven reverse tetracycline transactivator (rtTA), referred to here as YapTg. Organoids were seeded on day 0 from whole crypts isolated from Yap+/D, YapD/D, YapTg mice and cultured for 24 hours at which time they were harvested for transcriptome analysis by RNAseq.
Yap-dependent reprogramming of Lgr5(+) stem cells drives intestinal regeneration and cancer.
No sample metadata fields
View SamplesComparison of gene expresion profile of 4 SC clones and 4 SI clones at different time points defined a stabilization competency signiture required for successful reprogramming Overall design: mRNA profilling 4 SI clones at 5 time points, 4 SC clones at 6 time points, and 3 feeder samples.
A late transition in somatic cell reprogramming requires regulators distinct from the pluripotency network.
Specimen part, Subject
View SamplesDecreased mitochondrial mass and function in muscle of diabetic patients is associated with low PGC-1alpha, a transcriptional coactivator of the mitochondrial gene program. To investigate whether reduced PGC-1alpha and oxidative capacity in muscle directly contributes to age-related glucose intolerance, we compared the genetic signatures and metabolic profiles of aging mice lacking muscle PGC-1alpha. Microarray analysis revealed that a significant proportion of PGC-1alpha-dependent changes in gene expression overlapped with age-associated effects, and aging muscle and muscle lacking PGC-1alpha shared gene signatures of impaired electron transport chain activity and TGFbeta signalling.
Loss of Pgc-1α expression in aging mouse muscle potentiates glucose intolerance and systemic inflammation.
Specimen part
View SamplesGene regulatory networks that govern hematopoietic stem cells (HSC) and leukemiainitiating cells (L-IC) are deeply entangled. Thus, the discovery of compounds that target L-IC while sparing HSC is an attractive but difficult endeavor. Presently, most drug discovery approaches fail to counter-screen compounds against normal hematopoietic stem/progenitor cells (HSPC) to assess therapeutic index. Here, we present a combined in vitro and in vivo strategy to identify compounds specific to L-IC in acute myeloid leukemia (AML). A high-throughput screen of 4000 compounds on novel leukemia cell lines derived from human experimental leukemogenesis models yielded 80 hits, of which most were toxic to normal HSPC. Of the 10 compounds that passed this initial filter, we chose to characterize a single compound, kinetic riboside (KR), on AML L-IC and HSPC. KR demonstrated comparable efficacy to standard therapies against 63 primary AMLs. In vitro, KR effectively targeted the L-IC-enriched CD34+CD38- AML fraction, while sparing normal HSPC enriched fractions, although these effects were mitigated on HSC assayed in vivo, and highlights the importance of in vivo L-IC and HSC assays to measure function. Overall, we provide a novel approach to screen large drug libraries for the discovery of anti-L-IC compounds for human leukemias.
A small molecule screening strategy with validation on human leukemia stem cells uncovers the therapeutic efficacy of kinetin riboside.
Cell line, Treatment
View SamplesPeptide immunotherapy aims to specifically restore tolerance to the administered self-antigen and prevent autoimmunity without the perturbation of normal immune function. We have developed a dose escalation protocol for subcutaneous delivery of the MHC II-restricted myelin basic protein peptide analogue Ac1-9[4Y] to T cell receptor transgenic (Tg4) mice. Dose escalation allows safe administration of high doses of peptide, which effectively induces antigen-specific tolerance and suppresses the development of experimental autoimmune encephalomyelitis, a model for the human condition multiple sclerosis. CD4+ T cells isolated from treated mice are anergic and suppressive in vitro and respond to stimulation by secretion of the immunoregulatory cytokine IL-10. To understand the molecular changes occurring throughout the course of dose-escalation immunotherapy, we undertook microarray analysis of CD4+ T cells at different the stages of treatment, using Tg4 Rag-1 deficient mice, which lack naturally occurring regulatory T cells and have a monoclonal CD4+ T cell population
Sequential transcriptional changes dictate safe and effective antigen-specific immunotherapy.
Specimen part, Treatment
View SamplesThis scRNA-seq experiment is an integral part of a manuscript with the above title. Our analysis of the scRNA-seq data suggests that activated CARD11 promotes immunoglobulin class-switching in germinal center B cells and generation of IgG1-secreting plasma cells. Overall design: Single-cell suspensions were prepared from spleens harvested from mice 5 days post immunization with sheep red blood cells. B cells were enriched using an immunomagnetic negative selection kit. scRNA-seq was performed using the Chromium product suite by 10x Genomics.
Activated CARD11 accelerates germinal center kinetics, promoting mTORC1 and terminal differentiation.
Cell line, Subject
View Samples