Project description:Comparison of Mpl-/- mouse LSK cells, either treated with control (GFP) or Mpl lentivirus. Lineage negative bone marrow cells were isolated and transduced and transplanted into Mpl-/- recipient mice. After transplantation and follow up mice were sacrificed and LSK (lineage negative, Sca-1 positive, cKit positive) cells were isolated by FACS. RNA was isolated using RNeasy Micro Kit (Qiagen GmbH, Hilden, Germany) and RNA was amplified for microarray hybridization using the Nugen Ovation system (Nugen Technologies, AC Bemmel, Netherlands). The resulting material was hybridized to Affymetrix Mouse 430 2.0 arrays. RMA normalization and summarization was performed in R 2.10 using Bioconductor packages. The aim was to show the normalization of Mpl associated gene expression. 3 control (GFP transduced) samples of Mpl -/- mouse LSK cells and 3 treatment (Mpl transduced) samples of Mpl -/- mouse LSK cells.
Project description:Comparison of Mpl-/- mouse LSK cells, either treated with control (GFP) or Mpl lentivirus. Lineage negative bone marrow cells were isolated and transduced and transplanted into Mpl-/- recipient mice. After transplantation and follow up mice were sacrificed and LSK (lineage negative, Sca-1 positive, cKit positive) cells were isolated by FACS. RNA was isolated using RNeasy Micro Kit (Qiagen GmbH, Hilden, Germany) and RNA was amplified for microarray hybridization using the Nugen Ovation system (Nugen Technologies, AC Bemmel, Netherlands). The resulting material was hybridized to Affymetrix Mouse 430 2.0 arrays. RMA normalization and summarization was performed in R 2.10 using Bioconductor packages. The aim was to show the normalization of Mpl associated gene expression.
Project description:Thrombopoietin (Thpo) signals via its receptor Mpl and regulates megakaryopoiesis, hematopoietic stem cell (HSC) maintenance and post-transplant expansion. Mpl expression is tightly controlled and deregulation of Thpo/Mpl-signaling is linked to hematological disorders. Here, we constructed an intracellular-truncated, signaling deficient Mpl protein which is presented on the cell surface (dnMpl). The transplantation of bone marrow cells retrovirally transduced to express dnMpl into wildtype mice induced thrombocytopenia, and a progressive loss of HSC. Functional analysis of the truncated Mpl in vitro and in vivo demonstrated no internalization after Thpo binding and the inhibition of Thpo/Mpl-signaling in wildtype cells due to dominant-negative (dn) effects by receptor competition with wildtype Mpl for Thpo binding. Gene expression analysis was performerd of Lin-Sca1+cKit+ (LSK) cells isolated from mice transplanted with dnMpl transduced BM cells. The gene expression profile supported the exhaustion of HSC due to increased cell cycle progression and identified new and known downstream effectors of Thpo/Mpl-signaling in HSC (namely TIE2, ESAM1 and EPCR detected on the HSC-enriched LSK cell population). In summary, we established a novel way of Thpo/Mpl inhibition in the adult mouse and performed in depth analysis of the phenotype including gene expression profiling.
Project description:Thrombopoietin (Thpo) signals via its receptor Mpl and regulates megakaryopoiesis, hematopoietic stem cell (HSC) maintenance and post-transplant expansion. Mpl expression is tightly controlled and deregulation of Thpo/Mpl-signaling is linked to hematological disorders. Here, we constructed an intracellular-truncated, signaling deficient Mpl protein which is presented on the cell surface (dnMpl). The transplantation of bone marrow cells retrovirally transduced to express dnMpl into wildtype mice induced thrombocytopenia, and a progressive loss of HSC. Functional analysis of the truncated Mpl in vitro and in vivo demonstrated no internalization after Thpo binding and the inhibition of Thpo/Mpl-signaling in wildtype cells due to dominant-negative (dn) effects by receptor competition with wildtype Mpl for Thpo binding. Gene expression analysis was performerd of Lin-Sca1+cKit+ (LSK) cells isolated from mice transplanted with dnMpl transduced BM cells. The gene expression profile supported the exhaustion of HSC due to increased cell cycle progression and identified new and known downstream effectors of Thpo/Mpl-signaling in HSC (namely TIE2, ESAM1 and EPCR detected on the HSC-enriched LSK cell population). In summary, we established a novel way of Thpo/Mpl inhibition in the adult mouse and performed in depth analysis of the phenotype including gene expression profiling. BM cells were flushed from the femurs and tibias of C57Bl/6 donor mice. Lineage-marker negative (lin-) cells were isolated by magnetic cell sorting using lineage-specific antibodies (GR1, CD11b, CD45R/B220, CD3e, TER-119). Prior to viral transduction, lin- BM cells were prestimulated for 24-48h in StemSpan, containing 10 ng/ml murine SCF, 20 ng/ml murine Thpo, 10 ng/ml recombinant human FGF-1, 20 ng/ml murine IGF2, 1% penicillin/streptomycin, 2 mM glutamine. Lin- cells were transduced twice on two following days with an MOI of 10 with retroviral vectors on Retronectin coated and preloaded wells (10 μg/cm2). On day four after isolation, 5x10^5 cells/mouse were intravenously injected into lethally irradiated C57Bl/6 mice (10 Gy). Eight weeks after transplantation Lin-Sca1+cKit+ (LSK) cells were isolated from dnMpl and control transplanted mice by fluorescent activated cell sorting. For each sample, BM of 2-5 mice were pooled. RNA was isolated using RNeasy Micro Kit (Qiagen GmbH, Hilden, Germany). RNA quality was assessed using the Agilent 2100 Bioanalyzer.
Project description:Introgressed variants from other species can be an important source of genetic variation because they may arise rapidly, can include multiple mutations on a single haplotype, and have often been pretested by selection in the species of origin. Although introgressed alleles are generally deleterious, several studies have reported introgression as the source of adaptive alleles-including the rodenticide-resistant variant of Vkorc1 that introgressed from Mus spretus into European populations of Mus musculus domesticus. Here, we conducted bidirectional genome scans to characterize introgressed regions into one wild population of M. spretus from Spain and three wild populations of M. m. domesticus from France, Germany, and Iran. Despite the fact that these species show considerable intrinsic postzygotic reproductive isolation, introgression was observed in all individuals, including in the M. musculus reference genome (GRCm38). Mus spretus individuals had a greater proportion of introgression compared with M. m. domesticus, and within M. m. domesticus, the proportion of introgression decreased with geographic distance from the area of sympatry. Introgression was observed on all autosomes for both species, but not on the X-chromosome in M. m. domesticus, consistent with known X-linked hybrid sterility and inviability genes that have been mapped to the M. spretus X-chromosome. Tract lengths were generally short with a few outliers of up to 2.7 Mb. Interestingly, the longest introgressed tracts were in olfactory receptor regions, and introgressed tracts were significantly enriched for olfactory receptor genes in both species, suggesting that introgression may be a source of functional novelty even between species with high barriers to gene flow.
Project description:PURPOSE: To provide a detailed gene expression profile of the normal postnatal mouse cornea. METHODS: Serial analysis of gene expression (SAGE) was performed on postnatal day (PN)9 and adult mouse (6 week) total corneas. The expression of selected genes was analyzed by in situ hybridization. RESULTS: A total of 64,272 PN9 and 62,206 adult tags were sequenced. Mouse corneal transcriptomes are composed of at least 19,544 and 18,509 unique mRNAs, respectively. One third of the unique tags were expressed at both stages, whereas a third was identified exclusively in PN9 or adult corneas. Three hundred thirty-four PN9 and 339 adult tags were enriched more than fivefold over other published nonocular libraries. Abundant transcripts were associated with metabolic functions, redox activities, and barrier integrity. Three members of the Ly-6/uPAR family whose functions are unknown in the cornea constitute more than 1% of the total mRNA. Aquaporin 5, epithelial membrane protein and glutathione-S-transferase (GST) omega-1, and GST alpha-4 mRNAs were preferentially expressed in distinct corneal epithelial layers, providing new markers for stratification. More than 200 tags were differentially expressed, of which 25 mediate transcription. CONCLUSIONS: In addition to providing a detailed profile of expressed genes in the PN9 and mature mouse cornea, the present SAGE data demonstrate dynamic changes in gene expression after eye opening and provide new probes for exploring corneal epithelial cell stratification, development, and function and for exploring the intricate relationship between programmed and environmentally induced gene expression in the cornea. Keywords: other
Project description:Recombinant insect baculoviral vectors (BV) efficiently transduce several types of cells in the brain and can possibly be used for gene therapy for brain disorders. To verify the suitability of using these viral vectors to develop gene therapy strategies in the brain, and to evaluate our method of virus purification, we evaluated immune reactions upon acute administration of BV that were purified by ion-exchange membrane chromatography with high-speed centrifugation or high-speed centrifugation alone into the mouse brain using microarray global gene expression profiling.
Project description:Translational research is commonly performed in the C57B6/J mouse strain, chosen for its genetic homogeneity and phenotypic uniformity. Here, we evaluate the suitability of the white-footed deer mouse (Peromyscus leucopus) as a model organism for aging research, offering a comparative analysis against C57B6/J and diversity outbred (DO) Mus musculus strains. Our study includes comparisons of body composition, skeletal muscle function, and cardiovascular parameters, shedding light on potential applications and limitations of P. leucopus in aging studies. Notably, P. leucopus exhibits distinct body composition characteristics, emphasizing reduced muscle force exertion and a unique metabolism, particularly in fat mass. Cardiovascular assessments showed changes in arterial stiffness, challenging conventional assumptions and highlighting the need for a nuanced interpretation of aging-related phenotypes. Our study also highlights inherent challenges associated with maintaining and phenotyping P. leucopus cohorts. Behavioral considerations, including anxiety-induced responses during handling and phenotyping assessment, pose obstacles in acquiring meaningful data. Moreover, the unique anatomy of P. leucopus necessitates careful adaptation of protocols designed for Mus musculus. While showcasing potential benefits, further extensive analyses across broader age ranges and larger cohorts are necessary to establish the reliability of P. leucopus as a robust and translatable model for aging studies.
Project description:A transcriptome study in mouse hematopoietic stem cells was performed using a sensitive SAGE method, in an attempt to detect medium and low abundant transcripts expressed in these cells. Among a total of 31,380 unique transcript, 17,326 (55%) known genes were detected, 14,054 (45%) low-copy transcripts that have no matches to currently known genes. 3,899 (23%) were alternatively spliced transcripts of the known genes and 3,754 (22%) represent anti-sense transcripts from known genes.