Japanese patients with mitochondrial 3‑hydroxy‑3‑methylglutaryl‑CoA synthase deficiency: <em>In&nbsp;vitro</em> functional analysis of five novel <em>HMGCS2</em> mutations

Ago,Yasuhiko; Otsuka,Hiroki; Sasai,Hideo; Abdelkreem,Elsayed; Nakama,Mina; Aoyama,Yuka; Matsumoto,Hideki; Fujiki,Ryoji; Ohara,Osamu; Akiyama,Kazumasa; Fukui,Kaori; Watanabe,Yoriko; Nakajima,Yoko; Ohnishi,Hidenori; Ito,Tetsuya; Fukao,Toshiyuki

doi:10.3892/etm.2020.9166

Japanese patients with mitochondrial 3‑hydroxy‑3‑methylglutaryl‑CoA synthase deficiency: In vitro functional analysis of five novel HMGCS2 mutations

Authors:
- Yasuhiko Ago
- Hiroki Otsuka
- Hideo Sasai
- Elsayed Abdelkreem
- Mina Nakama
- Yuka Aoyama
- Hideki Matsumoto
- Ryoji Fujiki
- Osamu Ohara
- Kazumasa Akiyama
- Kaori Fukui
- Yoriko Watanabe
- Yoko Nakajima
- Hidenori Ohnishi
- Tetsuya Ito
- Toshiyuki Fukao
View Affiliations

Affiliations: Department of Pediatrics, Graduate School of Medicine, Gifu University Hospital, Gifu, Gifu 501‑1194, Japan, Department of Pediatrics, Faculty of Medicine, Sohag University, Sohag 82524, Egypt, Department of Biomedical Sciences, College of Life and Health Sciences, Education and Training Center of Medical Technology, Chubu University, Kasugai, Aichi 487‑8501, Japan, Department of Applied Genomics, Kazusa DNA Research Institute, Kisarazu, Chiba 292‑0818, Japan, Akiyama Children's Clinic, Kitami, Hokkaido 090‑0051, Japan, Department of Pediatrics and Child Health, Kurume University School of Medicine, Kurume, Fukuoka 830‑0011, Japan, Department of Pediatrics, Fujita Health University School of Medicine, Toyoake, Aichi 470‑1192, Japan
Published online on: September 1, 2020 https://doi.org/10.3892/etm.2020.9166
Article Number: 39
Copyright: © Ago et al. This is an open access article distributed under the terms of Creative Commons Attribution License.

Metrics: Total Views: 0 (Spandidos Publications: | PMC Statistics: )

Metrics: Total PDF Downloads: 0 (Spandidos Publications: | PMC Statistics: )

Cited By (CrossRef): 0 citations Loading Articles...

Abstract

Mitochondrial 3‑hydroxy‑3‑methylglutaryl‑CoA synthase (HMGCS2) deficiency is a metabolic disorder caused by mutations in the HMGCS2 gene. The present study describes the identification of four cases of HMGCS2 deficiency in Japan. Hepatomegaly and severe metabolic acidosis were observed in all cases. Fatty liver was identified in three cases, which suggested the unavailability of fatty acids. All patients presented with a high C2/C0 ratio, suggesting that the fatty acid oxidation pathway was normal during metabolic crisis. Genetic analyses revealed five rare, novel variants (p.G219E, p.M235T, p.V253A, p.S392L and p.R500C) in HMGCS2. To confirm their pathogenicity, a eukaryotic expression system and a bacterial expression system was adopted that was successfully used to obtain affinity‑purified HMGCS2 protein with measurable activity. Purified M235T, S392L and R500C proteins did not retain any residual activity, whilst the V253A variant showed some residual enzymatic activity. Judging from the transient expression experiment in 293T cells, the G219E variant appeared to be unstable. In conclusion, the present study identified five novel variants of HMGCS2 that were indicated to be pathogenic in four patients affected by HMGCS2 deficiency.

View Figures

View References

1	Mitchell GA and Fukao T: Inborn errors of ketone body metabolism. In: The metabolic & molecular basis of inherited disease. Scriver CR, Beaudet AL, Sly WS and Valle D (eds.). McGraw-Hill, New York, pp2327-2356, 2001.
2	Sass JO: Inborn errors of ketogenesis and ketone body utilization. J Interit Metab Dis. 35:23–28. 2012.PubMed/NCBI View Article : Google Scholar
3	Hegardt FG: Mitochondrial 3-hydroxy-3-methylglutaryl-CoA synthase: A control enzyme in ketogenesis. Biochem J. 338:569–582. 1999.PubMed/NCBI
4	Williamson DH, Bates MW and Krebs HA: Activity and intracellular distribution of enzymes of ketone-body metabolism in rat liver. Biochem J. 108:353–361. 1968.PubMed/NCBI View Article : Google Scholar
5	Boukaftane Y and Mitchell GA: Cloning and characterization of the human mitochondrial 3-hydroxy-3-methylglutaryl CoA synthase gene. Gene. 195:121–126. 1997.PubMed/NCBI View Article : Google Scholar
6	Fukao T, Mitchell G, Sass JO, Hori T, Orii K and Aoyama Y: Ketone body metabolism and its defects. J Inherit Metab Dis. 37:541–551. 2014.PubMed/NCBI View Article : Google Scholar
7	Wolf NI, Rahman S, Clayton PT and Zschocke J: Mitochondrial HMG-CoA synthase deficiency: Identification of two further patients carrying two novel mutations. Eur J Pediatr. 162:279–280. 2003.PubMed/NCBI View Article : Google Scholar
8	Carpenter KH, Bhattacharya K, Ellaway C, Zschocke J and Pitt JJ: Improved sensitivity for HMG CoA synthase detection using key markers on organic acid screen. J Inherit Metab Dis. 33(S62)2010.
9	Sass JO, Kuhlwein E, Klauwer D, Rohrbach M and Baumgartner MR: Hemodiafiltration in mitochondrial 3-hydroxy-3-methylglutaryl coenzyme A synthase (HMG-CoA synthase) deficiency. J Inherit Metab Dis. 36 (Suppl 2)(S189)2013.
10	Pitt JJ, Peters H, Boneh A, Yaplito-Lee J, Wieser S, Hinderhofer K, Johnson D and Zschocke J: Mitochondrial 3-hydroxy-3-methylglutaryl-CoA synthase deficiency: Urinary organic acid profiles and expanded spectrum of mutations. J Inherit Metab Dis. 38:459–466. 2015.PubMed/NCBI View Article : Google Scholar
11	Conboy E, Vairo F, Schultz M, Agre K, Ridsdale R, Deyle D, Oglesbee D, Gavrilov D, Klee EW and Lanpher B: Mitochondrial 3-hydroxy-3-methylglutaryl-CoA synthase deficiency: Unique presenting laboratory values and a review of biochemical and clinical features. JIMD Rep. 40:63–69. 2018.PubMed/NCBI View Article : Google Scholar
12	Lee T, Takami Y, Yamada K, Kobayashi H, Hasegawa Y, Sasai H, Otsuka H, Takeshima Y and Fukao T: A Japanese case of mitochondrial 3-hydroxy-3-methylglutaryl-CoA synthase deficiency who presented with severe metabolic acidosis and fatty liver without hypoglycemia. JIMD Rep. 48:19–25. 2019.PubMed/NCBI View Article : Google Scholar
13	Morris AA, Lascelles CV, Olpin SE, Lake BD, Leonard JV and Quant PA: Hepatic mitochondrial 3-hydroxy-3-methylglutaryl-coenzyme a synthase deficiency. Pediatr Res. 44:392–396. 1998.PubMed/NCBI View Article : Google Scholar
14	Kimura M, Yamamoto T and Yamaguchi S: Automated metabolic profiling and interpretation of GC/MS data for organic acidemia screening: A personal computer-based system. Tohoku J Exp Med. 188:317–334. 1999.PubMed/NCBI View Article : Google Scholar
15	Fujiki R, Ikeda M, Yoshida A, Akiko M, Yao Y, Nishimura M, Matsushita K, Ichikawa T, Tanaka T, Morisaki H, et al: Assessing the accuracy of variant detection in cost-effective gene panel testing by next-generation sequencing. J Mol Diagn. 20:572–582. 2018.PubMed/NCBI View Article : Google Scholar
16	Li H and Durbin R: Fast and accurate short read alignment with burrows-wheeler transform. Bioinformatics. 25:1754–160. 2009.PubMed/NCBI View Article : Google Scholar
17	Koboldt DC, Zhang Q, Larson DE, Shen D, McLellan MD, Lin L, Miller CA, Mardis ER, Ding L and Wilson RK: VarScan 2: Somatic mutation and copy number alteration discovery in cancer by exome sequencing. Genome Res. 22:568–576. 2012.PubMed/NCBI View Article : Google Scholar
18	McKenna A, Hanna M, Banks E, Sivachenko A, Cibulskis K, Kernytsky A, Garimella K, Altshuler D, Gabriel S, Daly M and DePristo MA: The genome analysis toolkit: A MapReduce framework for analyzing next-generation DNA sequencing data. Genome Res. 20:1297–1303. 2010.PubMed/NCBI View Article : Google Scholar
19	Van der Auwera GA, Carneiro MO, Hartl C, Poplin R, Del Angel G, Levy-Moonshine A, Jordan T, Shakir K, Roazen D, Thibault J, et al: From FastQ data to high confidence variant calls: The genome analysis toolkit best practices pipeline. Curr Protoc Bioinformatics. 43:11.10.1–11.10.33. 2013.PubMed/NCBI View Article : Google Scholar
20	Schwarz JM, Cooper DN, Schuelke M and Seelow D: MutationTaster2: Mutation prediction for the deep-sequencing age. Nat Methods. 11:361–362. 2014.PubMed/NCBI View Article : Google Scholar
21	Song XQ, Fukao T, Yamaguchi S, Miyazawa S, Hashimoto T and Orii T: Molecular cloning and nucleotide sequence of complementary DNA for human hepatic cytosolic acetoacetyl-coenzyme A thiolase. Biochem Biophys Res Commun. 201:478–485. 1994.PubMed/NCBI View Article : Google Scholar
22	Bradford MM: A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem. 72:248–254. 1976.PubMed/NCBI View Article : Google Scholar
23	Clinkenbeard KD, Reed WD, Mooney RA and Lane MD: Intracellular localization of the 3-hydroxy-3-methylglutaryl coenzme A cycle enzymes in liver. Separate cytoplasmic and mitochondrial 3-hydroxy-3-methylglutaryl coenzyme A generating systems for cholesterogenesis and ketogenesis. J Biol Chem. 250:3108–3116. 1975.PubMed/NCBI
24	Lowe DM and Tubbs PK: 3-Hydroxy-3-methylglutaryl-coenzyme A synthase from ox liver Properties of its acetyl derivative. Biochem J. 227:601–607. 1985.PubMed/NCBI View Article : Google Scholar
25	Rardin MJ, He W, Nishida Y, Newman JC, Carrico C, Danielson SR, Guo A, Gut P, Sahu AK, Li B, et al: SIRT5 regulates the mitochondrial lysine succinylome and metabolic networks. Cell Metab. 18:920–933. 2013.PubMed/NCBI View Article : Google Scholar
26	Decker K: Acetoacetyl Coenzyme A. In: Methods of enzymatic analysis. 3rd edition, Vol. 7, Metabolites 2: Tri- and dicarboxylic acids, purines, pyrimidines and derivatives, coenzymes, inorganic compounds. Bergmeyer HU, Bergmeyer J and Graßl M (eds.). Wiley-Blackwell, Hoboken, pp201-206, 1985.
27	Aledo R, Zschocke J, Pié J, Mir C, Fiesel S, Mayatepek E, Hoffmann GF, Casals N and Hegardt FG: Genetic basis of mitochondrial HMG-CoA synthase deficiency. Hum Genet. 109:19–23. 2001.PubMed/NCBI View Article : Google Scholar
28	Ramos M, Menao S, Arnedo M, Puisac B, Gil-Rodríguez MC, Teresa-Rodrigo ME, Hernández-Marcos M, Pierre G, Ramaswami U, Baquero-Montoya C, et al: New case of mitochondrial HMG-CoA synthase deficiency Functional analysis of eight mutations. Eur J Med Genet. 56:411–415. 2013.PubMed/NCBI View Article : Google Scholar
29	Neupert W: Protein import into mitochondria. Annu Rev Biochem. 66:863–917. 1997.PubMed/NCBI View Article : Google Scholar
30	Fukao T, Yamaguchi S, Scriver CR, Dunbar G, Wakazono A, Kano M, Orii T and Hashimoto T: Molecular studies of mitochondrial acetoacetyl-coenzyme A thiolase deficiency in the two original families. Hum Mutat. 2:214–220. 1993.PubMed/NCBI View Article : Google Scholar
31	Puisac B, Marcos-Alcalde I, Hernandez-Marcos M, Tobajas Morlana P, Levtova A, Schwahn BC, DeLaet C, Lace B, Gómez-Puertas P and Pié J: Human mitochondrial HMG-CoA synthase deficiency: Role of enzyme dimerization surface and characterization of three new patients. Int J Mol Sci. 19(1010)2018.PubMed/NCBI View Article : Google Scholar
32	Kompare M and Rizzo WB: Mitochondrial fatty-acid oxidation disorders. Semin Pediatr Neurol. 15:140–149. 2008.PubMed/NCBI View Article : Google Scholar
33	Aledo R, Mir C, Dalton RN, Turner C, Pié J, Hegardt FG, Casals N and Champion MP: Refining the diagnosis of mitochondrial HMG-CoA synthase deficiency. J Inherit Metab Dis. 29:207–211. 2006.PubMed/NCBI View Article : Google Scholar
34	Lascelles CV and Quant PA: Investigation of human hepatic mitochondrial 3-hydroxy-3-methylglutaryl-coenzyme A synthase in postmortem or biopsy tissue. Clin Chim Acta. 260:85–96. 1997.PubMed/NCBI View Article : Google Scholar
35	Reed WD, Clinkenbeard D and Lane MD: Molecular and catalytic properties of mitochondrial (ketogenic) 3-hydroxy-3-methylglutaryl coenzyme A synthase of liver. J Biol Chem. 250:3117–3123. 1975.PubMed/NCBI
36	Romani AM: Cellular magnesium homeostasis. Arch Biochem Biophys. 512:1–23. 2011.PubMed/NCBI
37	Shafqat N, Turnbull A, Zschocke J, Oppermann U and Yue WW: Crystal structures of human HMG-CoA synthase isoforms provide insights into inherited ketogenesis disorders and inhibitor design. J Mol Biol. 398:497–506. 2010.PubMed/NCBI View Article : Google Scholar