Academic Journal

Functional assessment of homozygous ALDH18A1 variants reveals alterations in amino acid and antioxidant metabolism

التفاصيل البيبلوغرافية
العنوان: Functional assessment of homozygous ALDH18A1 variants reveals alterations in amino acid and antioxidant metabolism
المؤلفون: Colonna, Maxwell B, Moss, Tonya, Mokashi, Sneha, Srikanth, Sujata, Jones, Julie R, Foley, Jackson R, Skinner, Cindy, Lichty, Angie, Kocur, Anthony, Wood, Tim, Stewart, Tracy Murray, Casero Jr., Robert A, Flanagan-Steet, Heather, Edison, Arthur S, Lyons, Michael J, Steet, Richard
المساهمون: National Cancer Institute, Chan Zuckerberg Initiative, University of Pennsylvania, National Science Foundation
المصدر: Human Molecular Genetics ; volume 32, issue 5, page 732-744 ; ISSN 0964-6906 1460-2083
بيانات النشر: Oxford University Press (OUP)
سنة النشر: 2022
الوصف: Mono- and bi-allelic variants in ALDH18A1 cause a spectrum of human disorders associated with cutaneous and neurological findings that overlap with both cutis laxa and spastic paraplegia. ALDH18A1 encodes the bifunctional enzyme pyrroline-5-carboxylate synthetase (P5CS) that plays a role in the de novo biosynthesis of proline and ornithine. Here we characterize a previously unreported homozygous ALDH18A1 variant (p.Thr331Pro) in four affected probands from two unrelated families, and demonstrate broad-based alterations in amino acid and antioxidant metabolism. These four patients exhibit variable developmental delay, neurological deficits and loose skin. Functional characterization of the p.Thr331Pro variant demonstrated a lack of any impact on the steady-state level of the P5CS monomer or mitochondrial localization of the enzyme, but reduced incorporation of the monomer into P5CS oligomers. Using an unlabeled NMR-based metabolomics approach in patient fibroblasts and ALDH18A1-null human embryonic kidney cells expressing the variant P5CS, we identified reduced abundance of glutamate and several metabolites derived from glutamate, including proline and glutathione. Biosynthesis of the polyamine putrescine, derived from ornithine, was also decreased in patient fibroblasts, highlighting the functional consequence on another metabolic pathway involved in antioxidant responses in the cell. RNA sequencing of patient fibroblasts revealed transcript abundance changes in several metabolic and extracellular matrix-related genes, adding further insight into pathogenic processes associated with impaired P5CS function. Together these findings shed new light on amino acid and antioxidant pathways associated with ALDH18A1-related disorders, and underscore the value of metabolomic and transcriptomic profiling to discover new pathways that impact disease pathogenesis.
نوع الوثيقة: article in journal/newspaper
اللغة: English
DOI: 10.1093/hmg/ddac226
DOI: 10.1093/hmg/ddac226/46582485/ddac226.pdf
الاتاحة: https://doi.org/10.1093/hmg/ddac226
https://academic.oup.com/hmg/advance-article-pdf/doi/10.1093/hmg/ddac226/46582485/ddac226.pdf
https://academic.oup.com/hmg/article-pdf/32/5/732/49283191/ddac226.pdf
Rights: https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model
رقم الانضمام: edsbas.491F991A
قاعدة البيانات: BASE