Project description:Cellular models of propionic acidemia were generated using HepG2 cells that were edited by CRISPR gene editing to introduce the pathogenic PCCA c.1285-1416A>G variant associated with propionic acidemia, and a 7 bp deletion of a predicted hnRNP A1 binding motif (c.1285-1411delTAGAACA), which causes complete and partial activation of an 84 bp pseudoexon from intron 14 in the PCCA gene, respectively. Treatment by transfection of splice-switching antisense oligonucleotides (SSO) to block inclusion of the PCCA pseudoexon in mRNA, was used to investigate this as a potential therapeutic strategy.
Project description:The dataset comprises of seven samples described below
1. Muscle samples from three patients with late-onset PEO caused by compound heterozygous POLG variants
M0305 POLG W748S/R1096C
M1105 POLG A467T/T251I+P587L
M1804 POLG A467T/X1240G+35aa
2. Muscle sample from a patient with adPEO with heterozygous TWNK variants
M0230 TWNK p.Arg357Pro
3. Blood control samples from two patients with late-onset PEO caused by compound heterozygous POLG variants
DNA2012-1630_S1 POLG W748S/R1096C
DNA2018-0168_S2 POLG A467T/T251I+P587L
4. Muscle samples from healthy control individuals
DNA2018-0172_S4 Healthy control 2
DNA2018-0173_S5 Healthy control 1
Project description:Propionate is an abundant short-chain fatty acid in mammals, largely derived from gut microbiota production. Due to its abundance, propionate metabolism is essential to maintain systemic homeostasis. Inborn errors of essential metabolic enzymes in this pathway causes severe illness, such as the development of Propionic Acidemia in cases of Propionyl-CoA Carboxylase (PCC) deficiency. We and others have previously developed mouse models deficient in Pcca, encoding the alpha subunit of PCC, to study the systemic and liver-specific mechanisms of propionic acidemia. However, the role of PCC in the intestine, where propionate is primarily absorbed, is understudied. To investigate the gut-specific role of PCC, we developed a mouse knockout of Pcca using Villin-Cre (Pcca Vill) on a floxed Pcca (Pcca ff) background. Here, we demonstrate the phenotypes present in this model provided both a standard (chow) and high fat (HFD) diets.
Project description:We studied the combined effects of the H4K16 acylations in vivo using a mouse model of the metabolic disorder propionic acidemia (PA), which causes metabolic challenges and systemic shifts in acyl-CoA ratios. Our findings indicate that H4K16 acylations modulate transcriptional responses in a concerted manner, providing insights into an adaptive chromatin regulation in response to metabolic stress.
Project description:Inborn errors in Propionyl-CoA Carboxylase (Pcca/b) cause life threatening propionic acidemia. To understand the contribution of mitochondrial propionyl-CoA metabolism to cellular and systemic metabolic dysfunction, we generated inducible and tissue-specific knockout (KO) mouse models of Pcca. Adult inducible loss of Pcca results in acute metabolic decompensation resembling the inborn error. The liver-specific loss of Pcca largely recapitulates this in a sexually dimorphic manner. Propionate and pyruvate converge in the TCA cycle as major anaplerotic substrates. Paradoxically, the simultaneous KO of Pyruvate Carboxylase (Pcx) rescues the lethality of liver-specific Pcca KO male mice. Most metabolites suspected as deleterious in propionic acidemia are exacerbated in Pcca;Pcx double KO mice with the noted exception of methylcitrate suggesting the centrality of this metabolite to systemic toxicity. These data clarify relevant toxic biomarkers and suggest that rebalancing hepatic TCA cycle metabolism as critical to mitigate the adverse effects of alternative propionyl-CoA metabolism.
Project description:We studied the concerted effects of the H4K16 acylations in vivo using a mouse model of the metabolic disorder propionic acidemia (PA), which causes metabolic challenges and systemic shifts in acyl-CoA ratios. Our findings indicate that H4K16 acylations act in vivo in a coordinated manner, allowing fine-tuning of transcriptional responses to metabolic stresses. Our work provides insights into the adaptive mechanisms of chromatin regulation in response to metabolic challenges.
Project description:We studied the concerted effects of the H4K16 acylations in vivo using a mouse model of the metabolic disorder propionic acidemia (PA), which causes metabolic challenges and systemic shifts in acyl-CoA ratios. Our findings indicate that H4K16 acylations act in vivo in a coordinated manner, allowing fine-tuning of transcriptional responses to metabolic stresses. Our work provides insights into the adaptive mechanisms of chromatin regulation in response to metabolic challenges.
Project description:FOXE3 encodes a highly conserved transcription factor essential for lens development, which is critical for proper eye formation. Biallelic variants in FOXE3 are associated with ocular anomalies, particularly complex microphthalmia (CM), characterized by defects in both the anterior segment and lens. Using next-generation sequencing (NGS) and Sanger sequencing, we identified a heterozygous nonsense variant in compound heterozygosity with a novel single nucleotide variant (SNV) located in a conserved non-coding region 3 kb upstream of FOXE3 in a patient with CM. Genetically engineered mouse lines carrying either the non-coding variant (Foxe3rv) or a frameshift mutation (Foxe3-) in homozygosity (Foxe3rv/rv and Foxe3-/-), along with compound heterozygous (Foxe3rv/Foxe3-) animals, revealed significant differences in the prevalence of ocular anomalies between wild-type controls and mice with homozygous or compound heterozygous mutations, highlighting the detrimental impact of these genetic variants. Furthermore, the progressive decline in FOXE3 protein levels across genotypes underscores its essential role in normal lens development and overall eye structure. These findings illuminate the intricate relationship between genetic variants and their effects on protein functionality and phenotype. In addition, our analysis demonstrated that the non-coding variant impairs USF2 binding, while Usf2 knockdown underscored its essential role in downregulating Foxe3, positioning it as a promising candidate gene in ocular development. These insights emphasize the importance of identifying disease-causing non-coding variants to enhance diagnostic precision for ocular developmental defects and to enrich our understanding of the regulatory mechanisms that govern eye development genes. Finally, this work provides new elements to understand the general mechanisms of ocular growth which, when impaired, leads to microphthalmia.
Project description:Similar to human patients, mice with the compound heterozygous mutation podocin R231Q/A268V, develop a late onset FSGS. Here, we did a proteomics anaylsis of kidney glomeruli before the onset of disease (mice at 3 weeks of age). Analysis of the data reveals that there are no developmental changes in the proteome of compund heterozygous mice.