RPS19 mutations are the most common cause of the human disorder Diamond Blackfan Anemia. The R62W mutation was hypothesized to act in a dominant negative fashion and mice expressing RPS19R62W have many of the characteristics of Diamond Blackfan Anemia.
A transgenic mouse model demonstrates a dominant negative effect of a point mutation in the RPS19 gene associated with Diamond-Blackfan anemia.
Specimen part
View SamplesRRP1B is a breast cancer metastasis suppressor that interacts with various regulators of gene transcription
Metastasis-associated protein ribosomal RNA processing 1 homolog B (RRP1B) modulates metastasis through regulation of histone methylation.
Specimen part, Cell line
View SamplesEKLF is a Krppel-like transcription factor identified as a transcriptional activator and chromatin modifier in erythroid cells. EKLF-deficient (Eklf -/-) mice die at day 14.5 of gestation from severe anemia. In this study, we demonstrate that early progenitor cells fail to undergo terminal erythroid differention in Eklf -/- embryos. To discover potential EKLF target genes responsible for the failure of erythropoiesis, transcriptional profiling was performed with RNA from wild type and Eklf -/- early erythroid progenitor cells. These analyses identified significant perturbation of a network of genes involved in cell cycle regulation, with the critical regulator of the cell cycle, E2f2, at a hub. E2f2 mRNA and protein levels were markedly decreased in Eklf -/- early erythroid progenitor cells, which showed a delay in the G1-to-S-phase transition. Chromatin immunoprecipitation analysis demonstrated EKLF occupancy at the proximal E2f2 promoter in vivo. Consistent with the role of EKLF as a chromatin modifier, EKLF binding-sites in the E2f2 promoter were located in a region of EKLF-dependent DNase I sensitivity in early erythroid progenitor cells. We propose a model in which EKLF-dependent activation and modification of the E2f2 locus is required for cell cycle progression preceding terminal erythroid differentiation.
Failure of terminal erythroid differentiation in EKLF-deficient mice is associated with cell cycle perturbation and reduced expression of E2F2.
Age, Specimen part
View SamplesThe Affymetrix Human Gene 2.0 ST array was used to measure differential expression of RNA isolated from normal and Diamond Blackfan anemia (DBA) erythroid progenitors after ex vivo expansion of circulating, peripheral blood derived hematopoietic stem cells under erythroid growth conditions. The gene-level probe summaries reported in this series were computed using RMA as implemented in the Bioconductor package Oligo v1.36.1.
Molecular convergence in ex vivo models of Diamond-Blackfan anemia.
Specimen part
View SamplesNdn is a candidate metastasis suppressor gene that has been reported to regulate transcription.
Necdin is a breast cancer metastasis suppressor that regulates the transcription of c-Myc.
Cell line
View SamplesAim of this project was the evaluation of the effect of flushing (intraportal and intraoperative) hepatic allografts with tacrolimus before transplantation. Group A was administered tacrolimus, 20ng/ml in 1500ml albumin solution; and Group B was administered only albumin solution. Wedge biopsie of the allograft were harvested after 15 min flushing time and the gene expression profile were determined.
Effect of intraportal infusion of tacrolimus on ischaemic reperfusion injury in orthotopic liver transplantation: a randomized controlled trial.
Specimen part, Treatment
View SamplesDiamond Blackfan anemia is a congenital bone marrow failure syndrome characterized by hypoproliferative anemia, often with associated physical abnormalities. Perturbations of the ribosome appear critically important to the development of DBA, as alterations in 9 different ribosomal protein genes have been identified in multiple unrelated families, along with rarer abnormalities of additional ribosomal proteins. However, presently only 50-60% of patients have an identifiable genetic lesion by ribosomal protein gene sequencing. Using genome-wide SNP array to evaluate for regions of recurrent copy variation, we identified 2 patients with mosaic loss in the region of the the chromosome 5-deleted region involved in somatically-acquired 5q- myelodysplastic syndrome.
Diminutive somatic deletions in the 5q region lead to a phenotype atypical of classical 5q- syndrome.
Sex, Specimen part, Disease, Disease stage, Treatment
View SamplesBackground Correct achievement of early ovarian folliculogenesis is a crucial phase for further ovarian function. This process is closely regulated by cell-cell interactions and coordinated expression of genes from oocyte and granulosa cells. But, despite of the large number of studies, little is known about the precise gene expression patterns driving early folliculogenesis. The experimental limitations concerned the very small size of these follicles and the mixture of the different developmental stages within an ovary that make the study of isolated follicular components much more difficult. The recently developed laser capture microdissection (LCM) technique coupled with microarrays experiments is promising in addressing the molecular specificity of each follicular compartment. Nevertheless, the isolation of unique cells or group of cells is still challenging to maintain RNA quality during this process and to obtain sufficient amount of RNA. In this study, we described a method allowing the analysis of oocyte and granulosa cells gene expression during the first stages of sheep early folliculogenesis. Results First we developed a new fixation protocol using a frizzed 70% ethanol fixation solution that ensures correct single cell capture and RNA integrity during microdissection time. After LCM capture of the compartments and follicular stages, RNA extraction and amplification, the expression of 6 oocyte-specific genes (SOHLH2, MAEL, MATER, VASA, GDF9, BMP15) and 3 granulosa cell-specific genes (KITLG, GATA4, AMH) confirmed the purity of the samples and documented their ovine expression profiles. Then, using bovine Affymetrix chip, we identified for the first time, a global gene expression for each follicular compartment during early developmental stages. Particularly the granulosa cell data set is quite unique. 1050 granulosa cell specific transcripts compared to oocyte and 759 oocyte specific transcripts were detected. The analysis of the expression of 2 genes (SIRT7, FST) confirmed this specificity of expression. Finally, the integration of the data stated the 3 main physiological events involved in early folliculogenesis and provided descriptive elements that confirmed the relevance and the potential of the LCM-derived RNAs. Conclusions This method should contribute through an additional genome wide expression profiling to give insights on molecular mechanisms involved in stage transitions and cell type interplays.
Transcriptome profiling of sheep granulosa cells and oocytes during early follicular development obtained by laser capture microdissection.
Age, Specimen part
View SamplesCalcium signaling is a central regulator of cardiomyocyte growth and function. Calmodulin is a critical mediator of calcium signals. Because the amount of calmodulin within cardiomyocytes is limiting, precise regulation of calmodulin expression may be an important for regulation of calcium signaling. In this study, we show for the first time that calmodulin levels are regulated post-transcriptionally in heart failure. The cardiomyocyte-restricted microRNA miR-1 inhibited translation of calmodulin-encoding mRNAs via highly conserved target sites within their 3-untranslated regions. In keeping with its effect on calmodulin expression, miR-1 downregulated calcium-calmodulin signaling through the calcineurin to NFAT. miR-1 also negatively regulated expression of Mef2a and Gata4, key transcription factors that mediate calcium-dependent changes in gene expression. Consistent with downregulation of these hypertrophy-associated genes, miR-1 attenuated cardiomyocyte hypertrophy in cultured neonatal rat cardiomyocytes and in the intact adult heart. Our data indicate that miR-1 regulates cardiomyocyte growth responses by negatively regulating the calcium-signaling components calmodulin, Mef2a, and Gata4.
MicroRNA-1 negatively regulates expression of the hypertrophy-associated calmodulin and Mef2a genes.
Cell line, Treatment, Time
View SamplesThe embryo lethal adenosine methylase tDNA knockout line SALK_074069 was partially complemented with its cDNA driven by the embryo specific ABI3 promoter (A6 lines). The plants have reduced adenosine methylation and show pleiotropic phenotypes. Rosette leaves were harvested from 3 week old plants, both wild-type and mutant plants in triplicate and analysed using the Affymetrix ATH1 array.
Adenosine Methylation in Arabidopsis mRNA is Associated with the 3' End and Reduced Levels Cause Developmental Defects.
Age, Specimen part
View Samples