ABSTRACT: Dysregulation of the Transforming Growth Factor Beta Pathway in Induced Pluripotent Stem Cells Generated from Patients with Diamond Blackfan Anemia
Project description:Dysregulation of the Transforming Growth Factor Beta Pathway in Induced Pluripotent Stem Cells Generated from Patients with Diamond Blackfan Anemia [HTA-2_0]
Project description:Dysregulation of the Transforming Growth Factor Beta Pathway in Induced Pluripotent Stem Cells Generated from Patients with Diamond Blackfan Anemia [HuEx-1_0]
Project description:Diamond Blackfan Anemia (DBA) is an inherited bone marrow failure syndrome with clinical features of red cell aplasia and variable developmental abnormalities. Most affected patients have heterozygous loss of function mutations in ribosomal protein genes but the pathogenic mechanism is still unknown. We generated induced pluripotent stem cells from DBA patients carrying RPS19 or RPL5 mutations. Transcriptome analysis revealed the striking dysregulation of the transforming growth factor beta signaling pathway in DBA lines. Expression of TGF beta target genes, such as TGFBI, BAMBI, COL3A1 and SERPINE1 was significantly increased in the DBA iPSCs. We quantified intermediates in canonical and non-canonical TGF beta pathways and observed a significant increase in the levels of the non-canonical pathway mediator p-JNK in the DBA iPSCs. Moreover, when the mutant cells were corrected by ectopic expression of WT RPS19 or RPL5, levels of p-JNK returned to normal. Surprisingly, nuclear levels of SMAD4, a mediator of canonical TGF beta signaling, were decreased in DBA cells due to increased proteolytic turnover. We also observed the up-regulation of TGF beta 1R, TGF beta 2, CDKN1A and SERPINE1 mRNA, and the significant decrease of GATA1 mRNA in the primitive multilineage progenitors. In summary our observations identify for the first time a dysregulation of the TGF beta pathway in the pathobiology of DBA. 6 Total human iPS samples were analyzed, including 2 wild type samples, 2 DBA samples with a RPS19 mutation, and 2 DBA samples with a RPL5 mutation. We generated the following pairwise comparisons using Partek Softare : RPS19 <WT; RPL5<WT. Genes with an FDR≤5% and a fold-change ≥2 were selected.
Project description:Diamond Blackfan Anemia (DBA) is an inherited bone marrow failure syndrome with clinical features of red cell aplasia and variable developmental abnormalities. Most affected patients have heterozygous loss of function mutations in ribosomal protein genes but the pathogenic mechanism is still unknown. We generated induced pluripotent stem cells from DBA patients carrying RPS19 or RPL5 mutations. Transcriptome analysis revealed the striking dysregulation of the transforming growth factor beta signaling pathway in DBA lines. Expression of TGF beta target genes, such as TGFBI, BAMBI, COL3A1 and SERPINE1 was significantly increased in the DBA iPSCs. We quantified intermediates in canonical and non-canonical TGF beta pathways and observed a significant increase in the levels of the non-canonical pathway mediator p-JNK in the DBA iPSCs. Moreover, when the mutant cells were corrected by ectopic expression of WT RPS19 or RPL5, levels of p-JNK returned to normal. Surprisingly, nuclear levels of SMAD4, a mediator of canonical TGF beta signaling, were decreased in DBA cells due to increased proteolytic turnover. We also observed the up-regulation of TGF beta 1R, TGF beta 2, CDKN1A and SERPINE1 mRNA, and the significant decrease of GATA1 mRNA in the primitive multilineage progenitors. In summary our observations identify for the first time a dysregulation of the TGF beta pathway in the pathobiology of DBA. 8 Total samples were analyzed, including 4 wild type samples, 2 RPS19 mutant samples, 2 corrected RPS19 mutant samples. We generated the following pairwise comparisons using Partek Softare : RPS19 mutant<WT; RPS19 mutant<corrected RPS19 mutant. Genes with an FDR?5% and a fold-change ?2 were selected.
Project description:Diamond Blackfan Anemia (DBA) is an inherited bone marrow failure syndrome with clinical features of red cell aplasia and variable developmental abnormalities. Most affected patients have heterozygous loss of function mutations in ribosomal protein genes but the pathogenic mechanism is still unknown. We generated induced pluripotent stem cells from DBA patients carrying RPS19 or RPL5 mutations. Transcriptome analysis revealed the striking dysregulation of the transforming growth factor beta signaling pathway in DBA lines. Expression of TGF beta target genes, such as TGFBI, BAMBI, COL3A1 and SERPINE1 was significantly increased in the DBA iPSCs. We quantified intermediates in canonical and non-canonical TGF beta pathways and observed a significant increase in the levels of the non-canonical pathway mediator p-JNK in the DBA iPSCs. Moreover, when the mutant cells were corrected by ectopic expression of WT RPS19 or RPL5, levels of p-JNK returned to normal. Surprisingly, nuclear levels of SMAD4, a mediator of canonical TGF beta signaling, were decreased in DBA cells due to increased proteolytic turnover. We also observed the up-regulation of TGF beta 1R, TGF beta 2, CDKN1A and SERPINE1 mRNA, and the significant decrease of GATA1 mRNA in the primitive multilineage progenitors. In summary our observations identify for the first time a dysregulation of the TGF beta pathway in the pathobiology of DBA.
Project description:Diamond Blackfan Anemia (DBA) is an inherited bone marrow failure syndrome with clinical features of red cell aplasia and variable developmental abnormalities. Most affected patients have heterozygous loss of function mutations in ribosomal protein genes but the pathogenic mechanism is still unknown. We generated induced pluripotent stem cells from DBA patients carrying RPS19 or RPL5 mutations. Transcriptome analysis revealed the striking dysregulation of the transforming growth factor beta signaling pathway in DBA lines. Expression of TGF beta target genes, such as TGFBI, BAMBI, COL3A1 and SERPINE1 was significantly increased in the DBA iPSCs. We quantified intermediates in canonical and non-canonical TGF beta pathways and observed a significant increase in the levels of the non-canonical pathway mediator p-JNK in the DBA iPSCs. Moreover, when the mutant cells were corrected by ectopic expression of WT RPS19 or RPL5, levels of p-JNK returned to normal. Surprisingly, nuclear levels of SMAD4, a mediator of canonical TGF beta signaling, were decreased in DBA cells due to increased proteolytic turnover. We also observed the up-regulation of TGF beta 1R, TGF beta 2, CDKN1A and SERPINE1 mRNA, and the significant decrease of GATA1 mRNA in the primitive multilineage progenitors. In summary our observations identify for the first time a dysregulation of the TGF beta pathway in the pathobiology of DBA.
Project description:Transcriptome profile of highly purified multipotential (P), erythroid (E), and myeloid (M) bone marrow progenitors from three RPS19 mutated Diamond-Blackfan anemia and six control human subjects. Two group comparison of sex and age matched subjects. Bone marrow progenitors, gene expression profiling, Diamond-Blackfan anemia, RPS19
Project description: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. Diamond-Blackfan Anemia (DBA), is an inherited erythroblastopenia associated with mutations in at least 8 different ribosomal protein genes. Mutations in the gene encoding Ribosomal Protein S19 (RPS19) have been identified in ~25% of DBA families. Most of these mutations disrupt either the translation or stability of the RPS19 protein and are predicted to cause DBA by haploinsufficiency. However, approximately ~30% of RPS19 mutations are missense mutations that do not alter the stability of the RPS19 protein and are hypothesized to act by a dominant negative mechanism. To formally test this hypothesis, we generated a transgenic mouse model expressing an RPS19 mutation in which an Arginine residue is replaced with a Tryptophan residue at codon 62 (RPS19R62W). Constitutive expression of RPS19R62W in developing mice was lethal. Conditional expression of RPS19R62W resulted in growth retardation, a mild anemia with reduced numbers of erythroid progenitors and significant inhibition of terminal erythroid maturation, similar to DBA. RNA profiling demonstrated over 700 dysregulated genes belonging to the same pathways that are disrupted in RNA profiles of DBA patient cells.
Project description:This RNA sequencing experiment is part of the study "Preclinical animal model of Diamond-Blackfan anemia with single amino acid mutation of ribosomal protein Rps19". A mouse model with arginine 67 mutation of ribosomal protein Rps19 develops features characteristic of human Diamond-Blackfan anemia, a rare bone marrow failure syndrome. These include hematologic dysfunctions, early onset growth delay, intrinsic anemia, severe craniofacial, skeletal, urogenital, cardiovascular, and cerebral abnormalities leading to premature lethality during the adolescence of the mouse. This model exhibits cell intrinsic activation of the Trp53 signaling pathway in hematopoietic stem cells (HSCs) leading to reduced erythroid lineage development that may be rescued after inactivation of the tumor suppressor Trp53. Using preliminary RNA sequencing study we identify a set of non-canonical components of the p53 signaling pathway which with high likelihood mediate the wide range of pathologies associated with DBA, the experiment if followed up by single cell transcriptome analysis of bone marrow hematopoietic progenitors and RNA sequencing of E14.5 fetal liver from wild-type control and Rps19R67∆/R67∆, Rps19R67∆/R67∆ Trp53−/− and Trp53−/− mutant embryos.