Project description:Regulatory B cells (Breg) express high levels of CD1d that presents lipid antigens to invariant natural killer T (iNKT) cells. The function of CD1d in Breg biology and iNKT cell activity during inflammation remains unclear. Here we show, using chimeric mice, cell depletion and adoptive cell transfer, that CD1d-lipid presentation by Bregs induces iNKT cells to secret IFN-γ to contribute, partially, to the down-regulation of T helper (Th)1 and Th17 adaptive immune responses for ameliorating experimental arthritis. Mice lacking CD1d-expressing B cells develop exacerbated diseases compared to wild-type mice, and fail to respond to α-galactosylceramide treatment. Absence of lipid presentation by B cells causes altered activation of iNKT cells, with disruption of regulatory pathways including those involved in metabolism and cytokine responses. Thus, we identify an IL-10-independent mechanism by which Bregs restrain excessive inflammation via lipid presentation.
Project description:Purpose: We aimed to identify miRNAs which are induced by the Activin/Nodal effectors, P-Smad2/3, in order to further our understanding of how P-Smad2/3 controls downstream gene expression in mouse ES cells to regulate crucial biological processes. Methods: We used a previously developed Tetracycline-On (Tet-On) system (TAG1) to manipulate the levels of P-Smad2/3 in mouse ES cells and performed an Illumina deep-sequencing screen to identify miRNAs which followed the P-Smad2/3 pathway. Results: We filtered the deep-seq data to identify a list of 28 miRNAs which showed a >1.25 fold increase in response to P-Smad2/3 induction and a >1.25 fold decrease in response to P-Smad2/3 repression. Conclusions: Our study represents a comprehensive global profiling of miRNA expression in response to changes in P-Smad2/3 levels in mouse ES cells. miRNA profiles of TAG1 cells which were untreated (control), SB-431541 treated (P-Smad2/3 repressed), or Dox treated (P-Smad2/3 induced), were generated using Illumina GAII.
Project description:Ribosome profiling is a technique that permits genome-wide, quantitative analysis of translation and has found broad application in recent years. Here, we describe a modified profiling protocol and software package designed to benefit more broadly the translation community in terms of simplicity and utility. The protocol, applicable to diverse organisms, including organelles, is based largely on previously published profiling methodologies, but employs duplex-specific nuclease as a convenient, bias-free, species-independent way to reduce rRNA contamination. Our protocol typically produces high levels of triplet periodicity, facilitating the detection of coding sequences, including upstream, downstream and overlapping open reading frames (ORFs). This feature also allows the identification of an alternative ribosome conformation evident during termination of protein synthesis. To test the effectiveness of DSN in ribosome profiling, we generated Ribo-Seq libraries from mouse tissue culture cells and from the green alga Chlamydomonas reinhardtii.
Project description:Purpose: Transcriptome is the entire repertoire of all transcripts present in a cell at any particular time. We undertook next-generation whole transcriptome sequencing approach to gain insight of the transcriptional landscape of the developing mouse lens. Methods: We ascertained mice lenses at six developmental time points including two embryonic (E15 and E18) and four postnatal stages (P0, P3, P6, and P9). The ocular tissue at each time point was maintained as two distinct pools serving as biological replicates for each developmental stage. The mRNA and small RNA libraries were paired-end sequenced on Illumina HiSeq 2000 and subsequently analyzed using bioinformatics tools. Results: Mapping of mRNA and small RNA libraries generated 187.56 and 154.22 million paired-end reads, respectively. We detected a total of 14,465 genes in the mouse ocular lens. Of these, 46 genes exhibited 40-fold differential expression compared to transcriptional levels at E15. Likewise, small RNA profiling identified 379 microRNAs (miRNAs) expressed in mouse lens. Of these, 49 miRNAs manifested an 8-fold or higher differential expression when compared, as above to the microRNA expression at E15. Conclusion: We report the first comprehensive profile of developing murine lens transcriptome including both mRNA and miRNA through next-generation RNA sequencing. A complete repository of the lens transcriptome of six developmental time points will be monumental in elucidating processes essential for development of the ocular lens and maintenance its transparency. Whole transcrtiome and microRNA profilling of mouse lens using 2 embryonic (E15 and E18) and 4 postnatal stages (P0, P3, P6 and P9) in duplicates through high-throughput sequening using Illumina HiSeq2000.
Project description:Bulk cancer cell populations are known to display distinct metabolic properties compared to their normal counterparts. However, relatively little is known about heterogeneity of metabolic properties within tumors. In this study we show that, analogous to some normal stem cells, breast tumor initiating cells (TICs, also called cancer stem cells) have distinct metabolic properties compared to non-tumorigenic cancer cells (NTCs). Transcriptome profiling using RNA-Seq revealed TICs under-express genes involved in mitochondrial oxidative phosphorylation and although TICs are relatively quiescent, they preferentially perform glycolysis over oxidative phosphorylation compared to NTCs. TICs contain fewer mitochondria and display lower expression and activity of pyruvate dehydrogenase (Pdh), a key regulator of oxidative phosphorylation. Metabolic reprogramming of TICs by pharmacologic activation of Pdh preferentially eliminates TICs in vitro and in vivo. Our findings reveal unique metabolic properties of TICs and indicate that metabolic reprogramming represents a promising strategy for targeting these cells. Examination transcriptome profiles for breast tumor initiating cells (TICs) and non-tumorigenic cells (NTCs)
Project description:Multiple system atrophy (MSA) is a fatal rapidly progressive Ia-synucleinopathy, characterized by prominent Ia-synuclein accumulation in oligodendrocytes. In this study we investigated miRNA expression in the substantia nigra and striatum of MSA transgenic mice (Tg(Plp1-SNCA)1Haa) and wild type controls. This forms part of a larger study in which we investigated miRNA-mRNA regulatory network in substantia nigra and striatum of MSA transgenic mice in pre-motor stage of neurodegenration.
Project description:We report the genome wide binding sites of BAP1, HCF1 and OGT in bone marrow derived macrophages. De-ubiquitinating enzyme BAP1 is mutated in a hereditary cancer syndrome with increased risk of mesothelioma and uveal melanoma. Somatic BAP1 mutations occur in various malignancies. We show that mouse Bap1 gene deletion is lethal during embryogenesis, but systemic or hematopoietic-restricted deletion in adults recapitulates features of human myelodysplastic syndrome (MDS). Knockin mice expressing BAP1 with a 3xFlag tag revealed that BAP1 interacts with host cell factor–1 (HCF-1), O-linked N-acetylglucosamine transferase (OGT), and the polycomb group proteins ASXL1 and ASXL2 in vivo. OGT and HCF-1 levels were decreased by Bap1 deletion, indicating a critical role for BAP1 in stabilizing these epigenetic regulators. Human ASXL1 is mutated frequently in chronic myelomonocytic leukemia (CMML) so an ASXL/BAP1 complex may suppress CMML. A BAP1 catalytic mutation found in a MDS patient implies that BAP1 loss of function has similar consequences in mice and humans. For BAP1, bone marrow derived macrophages were used differentiated from bone marrow cells of BAP1-3X Flag Tagged KI mice we generated. For OGT and HCF1, bone marrow derived macrophages were used from BAP1 WT mice.
Project description:The goal of this study is to identify the targets of RVE8, a MYB-like transcription factor involved in the circadian clock in Arabidopsis. Analysis of 7 days old rve8-1 RVE8::RVE8:GR and rve8-1 seedlings treated with dexamethasone or mock identified genes responsive to RVE8 induction.The RVE8 up-regulated genes are enriched for evening-phased genes while the down-regulated genes are enriched for a morning phase. This study reveals that RVE8 is a master regulator of circadian gene expression in Arabidopsis. Transgenic line rve8-1 RVE8::RVE8:GR and rve8-1 treated with DEX or mock with three biological replicates each, 12 samples in total.
Project description:Definitive hematopoiesis emerges during embryogenesis via an endothelial-to-hematopoietic transition. We attempted to induce this process in mouse fibroblasts by screening a panel of factors for hemogenic activity. We identified a combination of four transcription factors, Gata2, Gfi1b, cFos, and Etv6 that efficiently induces endothelial-like precursor cells with the subsequent appearance of hematopoietic cells. The precursor cells express a human CD34 reporter, Sca1 and Prominin1 within a global endothelial transcription program. Emergent hematopoietic cells possess nascent/specifying hematopoietic stem cell gene expression profiles and cell surface phenotypes. After transgene silencing and reaggregation culture, the specified cells generate hematopoietic colonies in vitro. Thus, we have shown that a simple combination of transcription factors is sufficient to induce a complex, dynamic and multi-step developmental program in vitro. These findings provide insights into the specification of definitive hemogenesis and a platform for future development of patient-specific stem/progenitor cells as well as more differentiated blood products. mRNA-seq profiling on populations generated after transduction with Gata2, Gfi1b, cFos and Etv6 at day 20 and day 35.
Project description:We identified total 174 significantly differentially expressed miRNAs between tumors and the normal tissues, and 109 miRNAs between serum from patients and serum from healthy individuals. There are only 10 common miRNAs. This suggests that only a small portion of tumor miRNAs are released into serum selectively. Interestingly, the expression change pattern of 28 miRNAs is opposite between breast cancer tumors and serum. Functional analysis shows that the differentially expressed miRNAs and their target genes form a complex interaction network affecting many biological processes and involving in cancer-related pathways such as prostate, basal cell carcinoma, acute myeloid leukymia, and more. A bunch of miRNAs have been demonstrated to be aberrantly expressed in cancer tumor tissue and serum. The miRNA signatures identified from the serum samples could serve as potential noninvasive diagnostic markers for breast cancer. The roles of the miRNAs in cancerigenesis is unclear. In this study, we generated the expression profiles of miRNAs from the paired breast cancer tumors, normal, tissue, and serum samples from eight patients using small RNA-sequencing. Serum samples from eight healthy individuals were used as normal controls.