AB001
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE43117 | GEO | 2014/01/30
SECONDARY ACCESSION(S): PRJNA184591
REPOSITORIES: GEO
Similar Datasets
Project description:Diamond-Blackfan anemia (DBA) is a congenital disorder that results predominantly from mutations in various ribosomal protein genes. In order to determine how these mutations affect the translation of specific mRNAs, we performed microarray analysis of polysomal transcripts isolated from lymphoblast cells derived from DBA patients carrying different haploinsufficient mutations in either RPS19 or RPL11. One of the few overlapping transcripts that we found significantly decreased on the polysomes codes for branched-chain aminotransferase-1 (BCAT-1). We go on to determine that translation of BCAT-1 is especially impaired in cells carrying mutations in the small ribosomal protein genes, and provide evidence that this effect is due to its unusually long 5M-bM-^@M-^YUTR. The BCAT-1 enzyme is critical for synthesis of the branched-chain amino acids, including leucine. It is known that DBA patients respond well to orally administered leucine, and large-scale clinical trials as such are currently underway. Our results suggest that the haploinsufficient loss of ribosomal protein genes results in a decrease of BCAT-1 translation and provide an explanation for why leucine administration is beneficial for DBA patients. In this expression study duplicate mRNA samples were generated from polysomes isolated from celllines with mutations in RPS19 or RPL11 or normal controls. In each group 3 cellines were tested. Duplicate samples were analyzed in dyeswap. As common reference the commercial universal human reference RNA (Stratagene) was used.
2014-01-30 | E-GEOD-43117 | biostudies-arrayexpress
Project description:Branched-chain aminotransferases (BCAT) are enzymes that initiate the catabolism of branched-chain amino acids (BCAA), such as leucine, thereby providing macromolecule precursors. In order to study the effect of BCAT1 inhibitor (ERG240) on LPS-polarized macrophage transcriptome, we stimulated monocyte derived macrophages (MDMs) with LPS for 8 hours, with or without the presence of ERG240. We then performed whole-genome transcriptome sequencing by RNA-sequencing (RNA-seq).
2020-11-23 | GSE148701 | GEO
Project description:Branched chain amino acids (BCAAs) play an important role in energy and protein regulation. Defects in BCAA metabolism are linked to numerous pathologies, including diabetes, neurodegeneration, and premature aging. Isovaleric acidemia is a metabolic disease caused by defective leucine breakdown and an abnormal accumulation of isovaleric acid in the body fluids; however, the cytotoxic effects caused by excess isovaleric acid remained unclear. Here, we provide a regulatory connection between BCAA metabolism and the ubiquitin/proteasome-system (UPS) in Caenorhabditis elegans. Multi-omic analysis identified that worms lacking the isovaleryl-CoA dehydrogenase IVD-1 exhibit reduced expression of regulatory proteasome subunits and defects in ubiquitin-dependent proteolysis. Conversely, proteasomal protein degradation was supported by the branched chain amino transferase BCAT-1. Adding extra isovaleric acid to the growth medium triggered UPS defects, implying a causative role of perturbed proteostasis in isovaleric academia.
2022-09-22 | PXD028286 | Pride
Project description:Diamond Blackfan Anemia (DBA) is associated with developmental defects and profound anemia. Mutations in genes encoding a ribosomal protein of the small (e.g. Rps19) or large (e.g. Rpl11) ribosomal subunit are found in over half of these patients. The mutations cause ribosomal haploinsufficiency, which reduces overall translation efficiency of cellular mRNAs. We reduced expression of *Rps19* or *Rpl11* in mouse erythroblasts and investigated mRNA polyribosome association, which revealed deregulated translation initiation of specific transcripts. Among these were *Bag1*, encoding a Hsp70 co-chaperone, and *Csde1*, encoding an RNA binding protein, both expressed at increased levels in erythroblasts. Their translation initiation is cap-independent and starts from an internal ribosomal entry site (IRES), which appeared sensitive to knock down of Rps19 or Rpl11. Mouse embryos lacking Bag1 die at embryonic day E13.5 with reduced erythroid colony forming cells in the fetal liver, and low Bag1 expression impairs erythroid differentiation in vitro. Reduced expression of Csde1 impairs proliferation and differentiation of erythroid blasts. Protein but not mRNA expression of *BAG1* and *CSDE1* was reduced in erythroblasts cultured from DBA patients. Our data suggest that impaired IRES-mediated translation of mRNAs expressed at increased levels in erythroblasts contributes to the erythroid phenotype of DBA. 3 biological replicates of erythroblasts treated with different shRNA were used for polyribosomal sucrose gradients; RNA was extracted from gradients in 2 samples - mRNA associated with polyribosomes (poly) and the rest (sub).
2011-11-14 | E-GEOD-22903 | biostudies-arrayexpress
Project description:Diamond Blackfan Anemia (DBA) is associated with developmental defects and profound anemia. Mutations in genes encoding a ribosomal protein of the small (e.g. Rps19) or large (e.g. Rpl11) ribosomal subunit are found in over half of these patients. The mutations cause ribosomal haploinsufficiency, which reduces overall translation efficiency of cellular mRNAs. We reduced expression of *Rps19* or *Rpl11* in mouse erythroblasts and investigated mRNA polyribosome association, which revealed deregulated translation initiation of specific transcripts. Among these were *Bag1*, encoding a Hsp70 co-chaperone, and *Csde1*, encoding an RNA binding protein, both expressed at increased levels in erythroblasts. Their translation initiation is cap-independent and starts from an internal ribosomal entry site (IRES), which appeared sensitive to knock down of Rps19 or Rpl11. Mouse embryos lacking Bag1 die at embryonic day E13.5 with reduced erythroid colony forming cells in the fetal liver, and low Bag1 expression impairs erythroid differentiation in vitro. Reduced expression of Csde1 impairs proliferation and differentiation of erythroid blasts. Protein but not mRNA expression of *BAG1* and *CSDE1* was reduced in erythroblasts cultured from DBA patients. Our data suggest that impaired IRES-mediated translation of mRNAs expressed at increased levels in erythroblasts contributes to the erythroid phenotype of DBA.
2011-11-14 | GSE22903 | GEO
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. The samples compared are RNA extracted from CD71 positive erythroblasts sorted from the bone marrow of wild type mice and mice expressing a mutant RPS19 (RPS19R62W) transgene
2011-06-29 | E-GEOD-22645 | biostudies-arrayexpress
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.
2011-06-29 | GSE22645 | GEO
Project description:Reproductive aging is one of the earliest human aging phenotypes, and mitochondrial dysfunction has been linked to a decline in oocyte quality. However, it is not known which mitochondrial metabolic processes are critical for oocyte quality maintenance with age. To understand how mitochondrial processes contribute to C. elegans oocyte quality, we characterized the mitochondrial proteomes of young and aged wild-type and long-reproductive daf-2 mutants. The mitochondrial proteomic profiles of young wild-type and daf-2 worms are similar and share upregulation of branched-chain amino acid (BCAA) metabolism pathway enzymes. Reduction of bcat-1 shortens reproduction, elevates mitochondrial ROS levels, and shifts mitochondrial localization. Moreover, bcat-1 knockdown decreases daf-2’s oocyte quality and reduces reproductive capability, indicating the importance of this pathway in the maintenance of oocyte quality with age. Importantly, we can delay oocyte quality deterioration and extend reproduction in wild-type animals both by bcat-1 overexpression and by supplementing with Vitamin B1, a cofactor needed for BCAA metabolism.
2024-01-15 | PXD048296 | Pride
Project description:Diamond Blackfan Anemia (DBA) is a rare, congenital erythrocyte aplasia that is usually caused by haploinsufficiency of ribosomal proteins due to diverse mutations in one of several ribosomal protein genes. A striking feature of this disease is that a range of different mutations in ribosomal proteins results in similar disease phenotypes primarily characterized by erythrocyte abnormalities and macrocytic anemia, while most other cell types are minimally affected. Previously, we analyzed the erythrocyte membrane proteomes of several DBA patients and identified several proteins that are not typically associated with this cell type that suggested inflammatory mechanisms contribute to the pathogenesis of DBA. In this study, we evaluated the erythrocyte cytosolic proteome of DBA patients through in-depth analysis of hemoglobin-depleted erythrocyte cytosol. The simple, reproducible, hemoglobin depletion using nickel columns enabled in-depth analysis of over 1000 cytosolic erythrocyte proteins with minimal subsequent fractionation of the proteome. Label-free quantitation and statistical analysis identified 29 proteins that were significantly changed in DBA patients compared to matched healthy control donors. Some of the proteins that were significantly increased in DBA erythrocyte cytoplasm included three proteasome subunit beta proteins that make up the immunoproteasome and proteins induced by interferon-γ such as n-myc interactor and interferon-induced 25 kDa protein [NMI and IFI35 respectively]. Pathway analysis confirmed the presence of an inflammatory signature with erythrocytes of DBA patients and predicted key upstream regulators including mitogen activated kinase 1, interferon-γ, tumor suppressor p53, and tumor necrosis factor. These results show that erythrocytes in DBA patients are intrinsically different from those in healthy controls which may be due to an inflammatory response resulting from the inherent molecular defect of ribosomal protein haploinsufficiency or changes in the bone marrow microenvironment that leads to red cell aplasia in DBA patients.
2018-10-24 | PXD002339 | Pride
Project description:Autism is present in 1% of the population, yet treatments are extremely limited. We identified homozygous inactivating mutations in the BCKDK gene in families presenting with autism and epilepsy. The encoded branched chain ketoacid dehydrogenase kinase protein is responsible for phosphorylation-mediated inactivation of the E1-alpha subunit of branched chain ketoacid dehydrogenase, itself mutated in Maple Syrup Urine Disease (MSUD). Patients with homozygous BCKDK mutations display reductions in BCKDK mRNA and protein, E1-alpha phosphorylation and serum branched chain amino acids (BCAAs). Bckdk knockout mice show abnormal brain amino acids profiles and neurobehavioral defects, which are largely corrected by dietary BCAA supplementation. Thus autism presenting with epilepsy due to BCKDK mutations represent a new and potentially treatable disease.
2012-07-18 | GSE39447 | GEO