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Deng IB, Follett J, Fox JD, Farrer MJ. Characterization of Dnajc12 knockout mice, a model of hypodopaminergia. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.06.602343. [PMID: 39026821 PMCID: PMC11257452 DOI: 10.1101/2024.07.06.602343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/20/2024]
Abstract
Homozygous DNAJC12 c.79-2A>G (p. V27Wfs*14) loss-of-function mutations were first reported as a cause of young-onset Parkinson's disease. However, bi-allelic autosomal recessive pathogenic variants in DNAJC12 may lead to an alternative constellation of neurological features including infantile dystonia, developmental delay, intellectual disability and neuropsychiatric disorders. DNAJC12 is understood to co-chaperone aromatic amino acid hydroxylases to enhance the synthesis of biogenic amines. In vitro , we confirm overexpressed DNAJC12 forms a complex with tyrosine hydroxylase, the rate-limiting enzyme in dopamine (DA) synthesis. Now we describe a conditional knockout mouse (cDKO) in which loxP sites flanking Dnajc12 exon 2 enable its excision by cre-recombinase to create a constitutive Dnajc12 knock out (DKO). At three months of age, DKO animals exhibit reduced locomotion and exploratory behavior in automated open-field testing. DKO mice also manifest increased plasma phenylalanine levels, a cardinal feature of patients with DNAJC12 pathogenic variants. In striatal tissue, total DA and serotonin, and their metabolites, are reduced. Biochemical alterations in synaptic proteins and tyrosine hydroxylase are also apparent, with enhanced phosphorylation of pSer31 and pSer40 sites that may reflect biological compensation. Electrically-evoked striatal DA is reduced. Most immediately, cDKO and DKO mice present models to develop and refined therapeutic approaches for the treatment of DNAJC12 dystonia and parkinsonism. These models may also enable the pleiotropic functions of biogenic amines (including DA) to be individually investigated in the brain and periphery.
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Martínez-Pizarro A, Picó S, López-Márquez A, Rodriguez-López C, Montalvo E, Alvarez M, Castro M, Ramón-Maiques S, Pérez B, Lucas JJ, Richard E, Desviat LR. PAH deficient pathology in humanized c.1066-11G>A phenylketonuria mice. Hum Mol Genet 2024; 33:1074-1089. [PMID: 38520741 PMCID: PMC11153335 DOI: 10.1093/hmg/ddae051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 02/12/2024] [Accepted: 03/12/2024] [Indexed: 03/25/2024] Open
Abstract
We have generated using CRISPR/Cas9 technology a partially humanized mouse model of the neurometabolic disease phenylketonuria (PKU), carrying the highly prevalent PAH variant c.1066-11G>A. This variant creates an alternative 3' splice site, leading to the inclusion of 9 nucleotides coding for 3 extra amino acids between Q355 and Y356 of the protein. Homozygous Pah c.1066-11A mice, with a partially humanized intron 10 sequence with the variant, accurately recapitulate the splicing defect and present almost undetectable hepatic PAH activity. They exhibit fur hypopigmentation, lower brain and body weight and reduced survival. Blood and brain phenylalanine levels are elevated, along with decreased tyrosine, tryptophan and monoamine neurotransmitter levels. They present behavioral deficits, mainly hypoactivity and diminished social interaction, locomotor deficiencies and an abnormal hind-limb clasping reflex. Changes in the morphology of glial cells, increased GFAP and Iba1 staining signals and decreased myelinization are observed. Hepatic tissue exhibits nearly absent PAH protein, reduced levels of chaperones DNAJC12 and HSP70 and increased autophagy markers LAMP1 and LC3BII, suggesting possible coaggregation of mutant PAH with chaperones and subsequent autophagy processing. This PKU mouse model with a prevalent human variant represents a useful tool for pathophysiology research and for novel therapies development.
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Affiliation(s)
- Ainhoa Martínez-Pizarro
- Centro de Biología Molecular Severo Ochoa UAM-CSIC, Universidad Autónoma de Madrid, Nicolás Cabrera 1, 28049 Madrid, Spain
- Instituto Universitario de Biología Molecular, UAM, Nicolás Cabrera 1, 28049 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), ISCIII, Av. Monforte de Lemos, 3-5. 28029 Madrid, Spain
- Instituto de Investigación Sanitaria Hospital La Paz (IdiPaz), Pedro Rico, 6, 28029 Madrid, Spain
| | - Sara Picó
- Centro de Biología Molecular Severo Ochoa UAM-CSIC, Universidad Autónoma de Madrid, Nicolás Cabrera 1, 28049 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), ISCIII, Av. Monforte de Lemos 3-5, 28029 Madrid, Spain
| | - Arístides López-Márquez
- Centro de Biología Molecular Severo Ochoa UAM-CSIC, Universidad Autónoma de Madrid, Nicolás Cabrera 1, 28049 Madrid, Spain
- Instituto Universitario de Biología Molecular, UAM, Nicolás Cabrera 1, 28049 Madrid, Spain
| | - Claudia Rodriguez-López
- Centro de Biología Molecular Severo Ochoa UAM-CSIC, Universidad Autónoma de Madrid, Nicolás Cabrera 1, 28049 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), ISCIII, Av. Monforte de Lemos 3-5, 28029 Madrid, Spain
| | - Elena Montalvo
- Centro de Biología Molecular Severo Ochoa UAM-CSIC, Universidad Autónoma de Madrid, Nicolás Cabrera 1, 28049 Madrid, Spain
- Instituto Universitario de Biología Molecular, UAM, Nicolás Cabrera 1, 28049 Madrid, Spain
| | - Mar Alvarez
- Centro de Biología Molecular Severo Ochoa UAM-CSIC, Universidad Autónoma de Madrid, Nicolás Cabrera 1, 28049 Madrid, Spain
| | - Margarita Castro
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), ISCIII, Av. Monforte de Lemos, 3-5. 28029 Madrid, Spain
- Instituto de Investigación Sanitaria Hospital La Paz (IdiPaz), Pedro Rico, 6, 28029 Madrid, Spain
- Centro de Diagnóstico de Enfermedades Moleculares (CEDEM), Francisco Tomás y Valiente 7, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Santiago Ramón-Maiques
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), ISCIII, Av. Monforte de Lemos, 3-5. 28029 Madrid, Spain
- Instituto de Biomedicina de Valencia (IBV-CSIC), Jaume Roig, 11, 46010 València, Valencia, Spain
| | - Belén Pérez
- Centro de Biología Molecular Severo Ochoa UAM-CSIC, Universidad Autónoma de Madrid, Nicolás Cabrera 1, 28049 Madrid, Spain
- Instituto Universitario de Biología Molecular, UAM, Nicolás Cabrera 1, 28049 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), ISCIII, Av. Monforte de Lemos, 3-5. 28029 Madrid, Spain
- Instituto de Investigación Sanitaria Hospital La Paz (IdiPaz), Pedro Rico, 6, 28029 Madrid, Spain
- Centro de Diagnóstico de Enfermedades Moleculares (CEDEM), Francisco Tomás y Valiente 7, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - José J Lucas
- Centro de Biología Molecular Severo Ochoa UAM-CSIC, Universidad Autónoma de Madrid, Nicolás Cabrera 1, 28049 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), ISCIII, Av. Monforte de Lemos 3-5, 28029 Madrid, Spain
| | - Eva Richard
- Centro de Biología Molecular Severo Ochoa UAM-CSIC, Universidad Autónoma de Madrid, Nicolás Cabrera 1, 28049 Madrid, Spain
- Instituto Universitario de Biología Molecular, UAM, Nicolás Cabrera 1, 28049 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), ISCIII, Av. Monforte de Lemos, 3-5. 28029 Madrid, Spain
- Instituto de Investigación Sanitaria Hospital La Paz (IdiPaz), Pedro Rico, 6, 28029 Madrid, Spain
| | - Lourdes R Desviat
- Centro de Biología Molecular Severo Ochoa UAM-CSIC, Universidad Autónoma de Madrid, Nicolás Cabrera 1, 28049 Madrid, Spain
- Instituto Universitario de Biología Molecular, UAM, Nicolás Cabrera 1, 28049 Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), ISCIII, Av. Monforte de Lemos, 3-5. 28029 Madrid, Spain
- Instituto de Investigación Sanitaria Hospital La Paz (IdiPaz), Pedro Rico, 6, 28029 Madrid, Spain
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Deng IB, Follett J, Bu M, Farrer MJ. DNAJC12 in Monoamine Metabolism, Neurodevelopment, and Neurodegeneration. Mov Disord 2024; 39:249-258. [PMID: 38014588 DOI: 10.1002/mds.29677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 10/04/2023] [Accepted: 11/09/2023] [Indexed: 11/29/2023] Open
Abstract
Recent studies show that pathogenic variants in DNAJC12, a co-chaperone for monoamine synthesis, may cause mild hyperphenylalaninemia with infantile dystonia, young-onset parkinsonism, developmental delay and cognitive deficits. DNAJC12 has been included in newborn screening, most revealingly in Spain, and those results highlight the importance of genetic diagnosis and early intervention in combating human disease. However, practitioners may be unaware of these advances and it is probable that many patients, especially adults, have yet to receive molecular testing for DNAJC12. Hence, this review summarizes genotype-phenotype relationships and treatment paradigms for patients with pathogenic variants in DNAJC12. It provides an overview of the structure of DNAJC12 protein, known genetic variants, domains, and binding partners, and elaborates on its role in monoamine synthesis, disease etiology, and pathogenesis. © 2023 International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Isaac Bul Deng
- Department of Neurology, University of Florida, Gainesville, Florida, USA
| | - Jordan Follett
- Department of Neurology, University of Florida, Gainesville, Florida, USA
| | - Mengfei Bu
- Department of Neurology, University of Florida, Gainesville, Florida, USA
| | - Matthew J Farrer
- Department of Neurology, University of Florida, Gainesville, Florida, USA
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Fino E, Barbato A, Scaturro GM, Procopio E, Balestrini S. DNAJC12 deficiency: Mild hyperphenylalaninemia and neurological impairment in two siblings. Mol Genet Metab Rep 2023; 37:101008. [PMID: 38053929 PMCID: PMC10694740 DOI: 10.1016/j.ymgmr.2023.101008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 09/09/2023] [Accepted: 09/10/2023] [Indexed: 12/07/2023] Open
Abstract
Background DNAJC12 co-chaperone protein deficiency has been recently described as a stand-alone metabolic disorder explaining many cases of mild hyperphenylalaninemia (HPA) that are not caused by variants in the PAH gene, which encodes for the hepatic enzyme phenylalanine hydroxylase (PAH), or inGCH1, PTS, QDPR, PCBD1 and DHPR, involved in tetrahydrobiopterin (BH4) biosynthesis and activity. Results We describe two sisters born to consanguineous parents. The youngest sister (Patient 1), initially asymptomatic, tested positive at NewBorn Screening (NBS) for mild HPA. After variants in the PAH and BH4 related-genes were excluded, we performed DNAJC12 genetic analysis and found a previously described homozygous deletion [NM_021800.3: c.58_59del p.(Gly20Metfs*2)]. The older sister (Patient 2), homozygous for the same variant and exhibiting mild HPA, was diagnosed subsequently and presented with ataxia and repeated falls, upper limb dyskinesia, intentional tremor, and mild intellectual disability. Patient 1 was started on treatment with low Phenylalanine (Phe) diet, BH4, l-3,4-dihydroxyphenylalanine/carbidopa (L-DOPA) and 5-OH-Tryptophan, soon after diagnosis, and despite poor adherence to the dietary regimen, only manifested language impairment at last follow-up (age 5 years and 4 months). Patient 2, who started the same treatment at school age, experienced a minimal progression of neurological symptoms, with some improvement in her motor skills. Conclusions These two new patients with DNAJC12-associated HPA, in addition to previous reports, point to DNAJC12 deficiency as a new metabolic syndrome that must be considered in patients with unexplained HPA.
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Affiliation(s)
- Edoardo Fino
- Meyer Children's Hospital IRCCS, Neuroscience Department, Florence, Italy
| | | | - Giusi M. Scaturro
- Meyer Children's Hospital IRCCS, Metabolic and Neuromuscular Unit, Florence, Italy
| | - Elena Procopio
- Meyer Children's Hospital IRCCS, Metabolic and Neuromuscular Unit, Florence, Italy
| | - Simona Balestrini
- Meyer Children's Hospital IRCCS, Neuroscience Department, Florence, Italy
- University of Florence, Florence, Italy
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Wong RSH, Mohammad S, Parayil Sankaran B, Junek R, Kim WT, Wotton T, Devanapalli B, Bandodkar S, Balasubramaniam S. Developmental delay and non-phenylketonuria (PKU) hyperphenylalaninemia in DNAJC12 deficiency: Case and approach. Brain Dev 2023; 45:523-531. [PMID: 37156708 DOI: 10.1016/j.braindev.2023.04.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 04/04/2023] [Accepted: 04/23/2023] [Indexed: 05/10/2023]
Abstract
BACKGROUND Hyperphenylalaninemia is a biomarker for several monogenic neurotransmitter disorders where the body cannot metabolise phenylalanine to tyrosine. Biallelic pathogenic variants in DNAJC12, co-chaperone of phenylalanine, tyrosine, and tryptophan hydroxylases, leads to hyperphenylalaninemia and biogenic amines deficiency. METHODS AND RESULTS A male firstborn to non-consanguineous Sudanese parents had hyperphenylalaninemia 247 µmol/L [reference interval (RI) < 200 µmol/L] at newborn screening. Dried blood spot dihydropteridine reductase (DHPR) assay and urine pterins were normal. He had severe developmental delay and autism spectrum disorder without a notable movement disorder. A low phenylalanine diet was introduced at two years without any clinical improvements. Cerebrospinal fluid (CSF) neurotransmitters at five years demonstrated low homovanillic acid (HVA) 0.259 µmol/L (reference interval (RI) 0.345-0.716) and 5-hydroxyindoleaetic acid (5HIAA) levels 0.024 µmol/L (reference interval (RI) 0.100-0.245). Targeted neurotransmitter gene panel analysis identified a homozygous c.78 + 1del variant in DNAJC12. At six years, he was commenced on 5-hydroxytryptophan 20 mg daily, and his protein-restricted diet was liberalised, with continued good control of phenylalanine levels. Sapropterin dihydrochloride 7.2 mg/kg/day was added the following year with no observable clinical benefits. He remains globally delayed with severe autistic traits. CONCLUSIONS Urine, CSF neurotransmitter studies, and genetic testing will differentiate between phenylketonuria, tetrahydrobiopterin or DNAJC12 deficiency, with the latter characterised by a clinical spectrum ranging from mild autistic features or hyperactivity to severe intellectual disability, dystonia, and movement disorder, normal DHPR, reduced CSF HIAA and HVA. DNAJC12 deficiency should be considered early in the differential workup of hyperphenylalaninemia identified from newborn screening, with its genotyping performed once deficiencies of phenylalanine hydroxylase (PAH) and tetrahydrobiopterin (BH4) have been biochemically or genetically excluded.
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Affiliation(s)
- Rachel Sze Hui Wong
- Metabolic Genetics Service, The Sydney Children's Hospitals Network, Westmead, NSW, Australia; TY Nelson Department of Neurology and Neurosurgery, The Children's Hospital at Westmead, Sydney, NSW, Australia
| | - Shekeeb Mohammad
- TY Nelson Department of Neurology and Neurosurgery, The Children's Hospital at Westmead, Sydney, NSW, Australia; Discipline of Child and Adolescent Health, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia
| | - Bindu Parayil Sankaran
- Discipline of Child and Adolescent Health, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia
| | - Rosie Junek
- NSW Newborn Screening (NBS) Programme, Sydney, NSW, Australia
| | - Won-Tae Kim
- NSW Newborn Screening (NBS) Programme, Sydney, NSW, Australia
| | - Tiffany Wotton
- NSW Newborn Screening (NBS) Programme, Sydney, NSW, Australia
| | - Beena Devanapalli
- NSW Biochemical Genetics Service, The Children's Hospital at Westmead, Westmead, NSW, Australia
| | - Sushil Bandodkar
- Department of Biochemistry, The Sydney Children's Hospital Network, Westmead, NSW, Australia; University of Sydney Children's Hospital at Westmead Clinical School, Faculty of Medicine and Health, Sydney, NSW, Australia
| | - Shanti Balasubramaniam
- Metabolic Genetics Service, The Sydney Children's Hospitals Network, Westmead, NSW, Australia; Discipline of Genomic Medicine, Sydney Medical School, University of Sydney, Sydney, NSW, Australia.
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Gunes D, Senturk L. A rare cause of hyperphenylalaninemia: four cases from a single family with DNAJC12 deficiency. J Pediatr Endocrinol Metab 2023; 36:791-797. [PMID: 37283250 DOI: 10.1515/jpem-2023-0049] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 05/28/2023] [Indexed: 06/08/2023]
Abstract
OBJECTIVES DNAJC12 deficiency (OMIM# 617384) is a new cause of hyperphenylalaninemia (HPA). The deficiency of the co-chaperone protein DNAJC12 was identified in 2017. To date, only 43 patients have been reported. Here, we report four patients from a single family with DNAJC12 deficiency while being followed up with a diagnosis of HPA. CASE PRESENTATION Two of the patients, who were cousins, were diagnosed with HPA by newborn screening. And the other two patients were siblings of these patients. Neurological examinations were normal except for one patient with mild learning disability. A c.158-2A>T p.(?) biallelic pathogenic variant was detected in intron 2 of the DNAJC12 gene. In the 24 h tetrahydrobiopterin (BH4) challenge test, there was a significant decrease in phenylalanine levels, especially at the 16th hour. Three patients had decreased homovalinic acid (HVA) and 5-hydroxyindoleacetic acid (5HIAA) in cerebrospinal fluid (CSF), while only one had decreased 5HIAA. In treatment, sapropterin, levodopa/carbidopa and 5-OH tryptophan were started. CONCLUSIONS We propose that it will be beneficial to evaluate the patients who have unexplained hyperphenylalaninemia for DNAJC12 deficiency. Patients with early diagnosis of neurotransmitter deficiency may be given a chance to be treated before clinical symptoms begin.
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Affiliation(s)
- Dilek Gunes
- Division of Inborn Metabolic Disease, Department of Pediatrics, Bezmialem Vakif University Hospital, İstanbul, Türkiye
| | - Leyli Senturk
- Department of Clinical Genetics, Istanbul Bagcilar Training and Research Hospital, İstanbul, Türkiye
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Restless legs syndrome in DNAJC12 deficiency. Neurol Sci 2023; 44:2167-2172. [PMID: 36897462 DOI: 10.1007/s10072-023-06733-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 03/04/2023] [Indexed: 03/11/2023]
Abstract
BACKGROUND Restless legs syndrome (RLS) is characterized by an unpleasant or painful sensation generally localized to lower limbs and relieved by movement. Its pathogenesis is hypothesized to involve the dopaminergic system, also in the light of the response of RLS to ex adiuvantibus treatment with dopamine agonists. DNAJC12 deficiency is a recently identified inherited metabolic disease coupling hyperphenylalaninemia to deficient dopaminergic and serotoninergic neurotransmission, due to the combined impairment of the three aromatic amino acids' (i.e., phenylalanine, tyrosine, and tryptophan) hydroxylases. DNAJC12 deficiency was reported in 43 patients so far, presenting with wide spectrum of clinical symptoms. CASE PRESENTATION RESULTS Here, we report RLS as a novel clinical manifestation of DNAJC12 deficiency, occurring in two adults while on treatment with L-dopa at longitudinal follow-up. The adjunct of low-dose pramipexole was effective in both patients to treat RLS. Besides, this treatment also allowed an improvement of dopaminergic homeostasis, as evidenced by clinical amelioration and stabilization of a peripheral short prolactin profile (a tool to indirectly evaluate dopaminergic homeostasis). DISCUSSION Besides including RLS as a new treatable clinical manifestation of DNAJC12, these observations may suggest the opportunity of a selective screening for DNAJC12 deficiency in patients with idiopathic RLS.
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Wang L, Ma D, Sun Y, Wang Y, Zeng H, Liu G, Zhang J, Xu Z. Identification of two novel DNAJC12 gene variants in a patient with mild hyperphenylalaninemia. Gene 2023; 869:147397. [PMID: 36990253 DOI: 10.1016/j.gene.2023.147397] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 03/16/2023] [Accepted: 03/22/2023] [Indexed: 03/30/2023]
Abstract
BACKGROUND Recently, variants in DNAJC12 were reported to be a novel genetic cause of hyperphenylalaninemia (HPA); however, thus far, fewer than fifty cases have been reported worldwide. Some patients with DNAJC12 deficiency present with mild HPA, developmental delay, dystonia, Parkinson's disease and psychiatric abnormalities. METHODS Herein, we report the case of a two-month-old Chinese infant with mild HPA, detected by newborn screening. Genetic etiology of the HPA patient was analyzed by Next-generation sequencing (NGS) and Sanger sequencing. Functional consequences of this variant were investigated using an in vitro minigene splicing assay. RESULTS Two novel compound heterozygous variants in DNAJC12, c.158-1G>A and c.336delG, were detected in our patient with asymptomatic HPA. The c.158-1G>A canonical splice-site variant demonstrated mis-splicing on an in vitro minigene assay and was predicted to lead to introduction of a premature termination codon p.(Val53AspfsTer15). In silico prediction tools designated c.336delG as a truncating variant leading to a frameshift p.(Met112IlefsTer44). Both variants segregated with unaffected parents and were annotated as "likely pathogenic". CONCLUSIONS In this study, we report an infant with mild HPA and compound heterozygous variants in DNAJC12. For patients with HPA, DNAJC12 deficiency should be considered when phenylalanine hydroxylase and tetrahydrobiopterin metabolic defects are excluded.
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Luo X, Wang R, Sun Y, Qiu W, Lu D, Wang Y, Gong Z, Zhang H, Han L, Liang L, Gu X, Yu Y, Xiao B. Deep Intronic PAH Variants Explain Missing Heritability in Hyperphenylalaninemia. J Mol Diagn 2023; 25:284-294. [PMID: 36849017 DOI: 10.1016/j.jmoldx.2023.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 01/18/2023] [Accepted: 02/02/2023] [Indexed: 02/27/2023] Open
Abstract
Phenylalanine hydroxylase (PAH) deficiency or phenylketonuria (PKU) is the most common cause of hyperphenylalaninemia (HPA), and approximately 5% of patients remain genetically unsolved. Identifying deep intronic PAH variants may help improve their molecular diagnostic rate. Next-generation sequencing was utilized to detect the whole PAH gene in 96 patients with genetically unsolved HPA from 2013 to 2022. The effects of deep intronic variants on pre-mRNA splicing were investigated by minigene-based assay. The allelic phenotype values of recurrent deep intronic variants were calculated. Twelve deep intronic PAH variants, located in intron 5 (c.509+434C>T), intron 6 (c.706+288T>G, c.706+519T>C, c.706+531T>C, c.706+535G>T, c.706+600A>C, c.706+603T>G, and c.706+608A>C), intron 10 (c.1065+241C>A and c.1065+258C>A), and intron 11 (c.1199+502A>T and c.1199+745T>A) were identified in 80.2% (77/96) patients. Ten of the 12 variants were novel, and they all generated pseudoexons in mRNA, leading to frameshift or lengthened proteins. The most prevalent deep intronic variant was c.1199+502A>T, followed by c.1065+241C>A, c.1065+258C>A, and c.706+531T>C. The metabolic phenotypes of the four variants were assigned as classic PKU, mild HPA, mild HPA, and mild PKU, respectively. The results suggest that deep intronic PAH variants improved the diagnostic rate from 95.3% to 99.3% in the overall patients with HPA. Our data demonstrate the importance of assessing noncoding variants in genetic diseases. Pseudoexon inclusion caused by deep intronic variants could represent a recurrent mechanism.
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Affiliation(s)
- Xiaomei Luo
- Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China; Shanghai Institute for Pediatric Research, Shanghai, China
| | - Ruifang Wang
- Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China; Shanghai Institute for Pediatric Research, Shanghai, China
| | - Yu Sun
- Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China; Shanghai Institute for Pediatric Research, Shanghai, China
| | - Wenjuan Qiu
- Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China; Shanghai Institute for Pediatric Research, Shanghai, China
| | - Deyun Lu
- Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China; Shanghai Institute for Pediatric Research, Shanghai, China
| | - Yu Wang
- Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China; Shanghai Institute for Pediatric Research, Shanghai, China
| | - Zhuwen Gong
- Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China; Shanghai Institute for Pediatric Research, Shanghai, China
| | - Huiwen Zhang
- Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China; Shanghai Institute for Pediatric Research, Shanghai, China
| | - Lianshu Han
- Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China; Shanghai Institute for Pediatric Research, Shanghai, China
| | - Lili Liang
- Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China; Shanghai Institute for Pediatric Research, Shanghai, China
| | - Xuefan Gu
- Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China; Shanghai Institute for Pediatric Research, Shanghai, China
| | - Yongguo Yu
- Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China; Shanghai Institute for Pediatric Research, Shanghai, China.
| | - Bing Xiao
- Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China; Shanghai Institute for Pediatric Research, Shanghai, China.
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Mastrangelo M, Tolve M, Artiola C, Bove R, Carducci C, Carducci C, Angeloni A, Pisani F, Leuzzi V. Phenotypes and Genotypes of Inherited Disorders of Biogenic Amine Neurotransmitter Metabolism. Genes (Basel) 2023; 14:genes14020263. [PMID: 36833190 PMCID: PMC9957200 DOI: 10.3390/genes14020263] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Revised: 01/11/2023] [Accepted: 01/17/2023] [Indexed: 01/21/2023] Open
Abstract
Inherited disorders of biogenic amine metabolism are genetically determined conditions resulting in dysfunctions or lack of enzymes involved in the synthesis, degradation, or transport of dopamine, serotonin, adrenaline/noradrenaline, and their metabolites or defects of their cofactor or chaperone biosynthesis. They represent a group of treatable diseases presenting with complex patterns of movement disorders (dystonia, oculogyric crises, severe/hypokinetic syndrome, myoclonic jerks, and tremors) associated with a delay in the emergence of postural reactions, global development delay, and autonomic dysregulation. The earlier the disease manifests, the more severe and widespread the impaired motor functions. Diagnosis mainly depends on measuring neurotransmitter metabolites in cerebrospinal fluid that may address the genetic confirmation. Correlations between the severity of phenotypes and genotypes may vary remarkably among the different diseases. Traditional pharmacological strategies are not disease-modifying in most cases. Gene therapy has provided promising results in patients with DYT-DDC and in vitro models of DYT/PARK-SLC6A3. The rarity of these diseases, combined with limited knowledge of their clinical, biochemical, and molecular genetic features, frequently leads to misdiagnosis or significant diagnostic delays. This review provides updates on these aspects with a final outlook on future perspectives.
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Affiliation(s)
- Mario Mastrangelo
- Child Neurology and Psychiatry Unit, Department of Human Neurosciences, Sapienza University of Rome, 00185 Rome, Italy
- Azienda Ospedaliero Universitaria Policlinico Umberto I, 00161 Rome, Italy
| | - Manuela Tolve
- Azienda Ospedaliero Universitaria Policlinico Umberto I, 00161 Rome, Italy
- Department of Experimental Medicine, Sapienza University of Rome, 00161 Rome, Italy
| | - Cristiana Artiola
- Azienda Ospedaliero Universitaria Policlinico Umberto I, 00161 Rome, Italy
- Department of Experimental Medicine, Sapienza University of Rome, 00161 Rome, Italy
| | - Rossella Bove
- Child Neurology and Psychiatry Unit, Department of Human Neurosciences, Sapienza University of Rome, 00185 Rome, Italy
| | - Claudia Carducci
- Azienda Ospedaliero Universitaria Policlinico Umberto I, 00161 Rome, Italy
- Department of Experimental Medicine, Sapienza University of Rome, 00161 Rome, Italy
| | - Carla Carducci
- Azienda Ospedaliero Universitaria Policlinico Umberto I, 00161 Rome, Italy
- Department of Experimental Medicine, Sapienza University of Rome, 00161 Rome, Italy
| | - Antonio Angeloni
- Azienda Ospedaliero Universitaria Policlinico Umberto I, 00161 Rome, Italy
- Department of Experimental Medicine, Sapienza University of Rome, 00161 Rome, Italy
| | - Francesco Pisani
- Child Neurology and Psychiatry Unit, Department of Human Neurosciences, Sapienza University of Rome, 00185 Rome, Italy
- Azienda Ospedaliero Universitaria Policlinico Umberto I, 00161 Rome, Italy
- Correspondence: ; Tel.: +39-649972930; Fax: +39-64440232
| | - Vincenzo Leuzzi
- Child Neurology and Psychiatry Unit, Department of Human Neurosciences, Sapienza University of Rome, 00185 Rome, Italy
- Azienda Ospedaliero Universitaria Policlinico Umberto I, 00161 Rome, Italy
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11
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Lin Y, Lin W, Su R, Zheng Z, Fu Q, Wang G. Newborn screening and genetic features of patients with hyperphenylalaninemia in a southern Chinese population. Clin Chim Acta 2022; 535:13-18. [PMID: 35952926 DOI: 10.1016/j.cca.2022.08.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 07/28/2022] [Accepted: 08/05/2022] [Indexed: 11/28/2022]
Abstract
BACKGROUND AND AIMS Hyperphenylalaninemia (HPA) is the most common congenital amino acid metabolism-related defect, but its incidence differs substantially between northern and southern China. We aimed to elucidate the incidence, proportion, and genetic features of HPA in a southern Chinese population. MATERIALS AND METHODS We analyzed the HPA screening results for 580,460 newborns from 2014 to 2021. RESULTS Of the 296 newborns who tested HPA positive, 56 were diagnosed with HPA, including 47 with phenylalanine hydroxylase deficiency and nine with tetrahydrobiopterin deficiency (BH4D). HPA incidence was estimated to be 1:10,365 newborns. All patients had elevated Phe and Phe/Tyr levels. Thirty-three PAH variants and five PTS variants were detected in HPA patients; 80.6 % PAH variants and 100 % PTS variants were classified as pathogenic or likely pathogenic. In silico tools predicted the remaining variants to be damaging. PAH variants clustered in exons 3, 5, 7, 11, and 12 and PTS variants clustered in exons 2 and 5. The most common PAH variants were c.158G > A (p.R53H, 22.3 %) and c.721C > T (p.R241C, 14.9 %). The most common PTS variants were c.155A > G (p.N52S, 50.0 %) and c.259C > T (p.P87S, 33.3 %). CONCLUSION Newborn screening is an effective method for early detection of HPA, but differential diagnosis of BH4D is necessary.
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Affiliation(s)
- Yiming Lin
- Center of Neonatal Disease Screening, Quanzhou Maternity and Children's Hospital, 700 Fengze Street, Quanzhou, Fujian Province 362000, China
| | - Weihua Lin
- Center of Neonatal Disease Screening, Quanzhou Maternity and Children's Hospital, 700 Fengze Street, Quanzhou, Fujian Province 362000, China
| | - Run Su
- Center of Neonatal Disease Screening, Quanzhou Maternity and Children's Hospital, 700 Fengze Street, Quanzhou, Fujian Province 362000, China
| | - Zhenzhu Zheng
- Center of Neonatal Disease Screening, Quanzhou Maternity and Children's Hospital, 700 Fengze Street, Quanzhou, Fujian Province 362000, China
| | - Qingliu Fu
- Center of Neonatal Disease Screening, Quanzhou Maternity and Children's Hospital, 700 Fengze Street, Quanzhou, Fujian Province 362000, China.
| | - Gaoxiong Wang
- Department of Surgery, Quanzhou Maternity and Children's Hospital, 700 Fengze Street, Quanzhou, Fujian Province 362000, China.
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12
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Khaghani F, Eshraghi P, Hamzehloei T. Tetrahydrobiopterin responsiveness in Phenylalanine hydroxylase deficient patients from North-east of Iran: Genotype-phenotype correlation, identification of a novel mutation and 7 new responsive genotypes. Eur J Med Genet 2022; 65:104536. [PMID: 35690318 DOI: 10.1016/j.ejmg.2022.104536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 04/03/2022] [Accepted: 06/05/2022] [Indexed: 11/03/2022]
Abstract
Phenylalanine hydroxylase enzyme defects result in a hereditary metabolic disorder called phenylketonuria. Sapropterin (tetrahydrobiopterin) is one of the treatment strategies for this disorder. Even though a correlation between genotype and BH4 responsiveness was established by earlier studies, a subset of mutations often presented inconsistent responses and/or phenotypes. Different genetic background is one of the potential reasons for this fact. In this study, the genotype of a total of 34 PAH deficient patients from Khorasan-Razavi providence in the north-east of Iran was obtained. Among this patients, 21 individuals took the 24 h and 48 h BH4 loading test and if the result was positive, their Phenylalanine tolerance was assessed. It is the first study of its type in patients from Iran to evaluate genotype role in predicting the most probable responsive individuals. The known pathogenic variant p.R169P and the novel variant p. Leu72_Asp75delinsTyr were first classified as responsive.Seven genotypes were reported as responsive for the first time. All patients carrying at least one pathogenic variant, which was previously reported as BH4 responsive, respond to BH4. Three patients with p.L48S, p.R261Q and p.A309V pathogenic variants were exceptions. There was no certain statistical correlation between genotype and response. Genotype and phenotype were significantly correlated and majority of patients with mild phenotype carried at least one non-null pathogenic variant. In Khorasan-Razavi province of Iran, patients with at least one non-null mutation are most probable to demonstrate mild phenotype and respond to BH4 phenotype.
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Affiliation(s)
- Faeze Khaghani
- Department of Medical Genetics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran; Medical Genetics Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Peyman Eshraghi
- Department of Pediatric and Endocrinology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Tayebeh Hamzehloei
- Medical Genetics Research Center, Mashhad University of Medical Sciences, Mashhad, Iran; Metabolic Syndrome Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
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13
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Deubiquitinase USP19 extends the residual enzymatic activity of phenylalanine hydroxylase variants. Sci Rep 2022; 12:14243. [PMID: 35987969 PMCID: PMC9392723 DOI: 10.1038/s41598-022-18656-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 08/17/2022] [Indexed: 11/09/2022] Open
Abstract
Phenylalanine hydroxylase (PAH) is a key enzyme in mammals that maintains the phenylalanine (Phe) concentration at an appropriate physiological level. Some genetic mutations in the PAH gene lead to destabilization of the PAH enzyme, leading to phenylketonuria (PKU). Destabilized PAH variants can have a certain amount of residual enzymatic activity that is sufficient for metabolism of Phe. However, accelerated degradation of those variants can lead to insufficient amounts of cellular PAH protein. The optimal protein level of PAH in cells is regulated by a balancing act between E3 ligases and deubiquitinating enzymes (DUBs). In this work, we analyzed the protein expression and stability of two PKU-linked PAH protein variants, R241C and R243Q, prevalent in the Asian population. We found that the tested PAH variants were highly ubiquitinated and thus targeted for rapid protein degradation. We demonstrated that USP19, a DUB that interacts with both PAH variants, plays a regulatory role by extending their half-lives. The deubiquitinating activity of USP19 prevents protein degradation and increases the abundance of both PAH protein variants. Thus, our study reveals a novel mechanism by which deubiquitinating activity of USP19 extends the residual enzymatic activity of PAH variants.
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14
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Minighin EC, de Sousa RCS, Ramos ALCC, Dias LTS, Labanca RA, de Araújo RLB. Evaluation of the Consumption of Fruits and Vegetables by Phenylketonurics in the Metabolic Control of Phenylalanine: An Integrative Review. J Med Food 2022; 25:487-494. [PMID: 35325557 DOI: 10.1089/jmf.2021.0111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Phenylketonuria (PKU) is an autosomal recessive disease caused by variants in the gene that encodes phenylalanine hydroxylase (PAH), limiting the metabolism of phenylalanine (Phe). When PAH activity is absent or hindered, Phe is not converted to tyrosine, leading to an accumulation of Phe in the blood, which can cause serious neurological complications. Once PKU is diagnosed, treatment should be started immediately, and the basis for this is dietary restriction of foods with high levels of Phe, associated with the use of protein substitutes and intake of foods with low protein content. This restriction accompanies patients throughout their lives, making their diets unpalatable and monotonous, which represents a major challenge for health professionals and patients, considering that these factors favor food transgression. In this context, the objective of this work was to carry out an integrative review based on evidence regarding the intake of fruits and vegetables, by phenylketonurics, taking into account the greater or lesser tolerance to Phe. Since, some researchers have dedicated themselves to evaluating the biochemical effect of unrestricted consumption of fruits and vegetables at PKU, unifying the information in this regard. It was observed that the intake of vegetable protein by patients with PKU has shown to be promising since the studies indicate that the intake of these proteins does not present adverse effects to the metabolic control of the Phe.
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Affiliation(s)
- Elaine Carvalho Minighin
- Department of Food Science, Faculty of Pharmacy, Universidade Federal de Minas Gerais, Pampulha Campus, Belo Horizonte, Minas Gerais, Brazil
| | - Roberto César Santos de Sousa
- Department of Food Science, Faculty of Pharmacy, Universidade Federal de Minas Gerais, Pampulha Campus, Belo Horizonte, Minas Gerais, Brazil
| | - Ana Luiza Coeli Cruz Ramos
- Department of Food Science, Faculty of Pharmacy, Universidade Federal de Minas Gerais, Pampulha Campus, Belo Horizonte, Minas Gerais, Brazil
| | - Lorena Thais Souza Dias
- Department of Food Science, Faculty of Pharmacy, Universidade Federal de Minas Gerais, Pampulha Campus, Belo Horizonte, Minas Gerais, Brazil
| | - Renata Adriana Labanca
- Department of Food Science, Faculty of Pharmacy, Universidade Federal de Minas Gerais, Pampulha Campus, Belo Horizonte, Minas Gerais, Brazil
| | - Raquel Linhares Bello de Araújo
- Department of Food Science, Faculty of Pharmacy, Universidade Federal de Minas Gerais, Pampulha Campus, Belo Horizonte, Minas Gerais, Brazil
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15
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Lin C, Li Y, Zhang E, Feillet F, Zhang S, Blau N. Importance of the long non-coding RNA (lncRNA) transcript HULC for the regulation of phenylalanine hydroxylase and treatment of phenylketonuria. Mol Genet Metab 2022; 135:171-178. [PMID: 35101330 DOI: 10.1016/j.ymgme.2022.01.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 01/18/2022] [Accepted: 01/18/2022] [Indexed: 12/12/2022]
Abstract
More than 1280 variants in the phenylalanine hydroxylase (PAH) gene are responsible for a broad spectrum of phenylketonuria (PKU) phenotypes. While the genotype-phenotype correlation is reaching 88%, for some inconsistent phenotypes with the same genotype additional factors like tetrahydrobiopterin (BH4), the PAH co-chaperone DNAJC12, phosphorylation of the PAH residues or epigenetic factors may play an important role. Very recently an additional player, the long non-coding RNA (lncRNA) transcript HULC, was described to regulate PAH activity and enhance residual enzyme activity of some PAH variants (e.g., the most common p.R408W) by using HULC mimics. In this review we present an overview of the lncRNA function and in particular the interplay of the HUCL transcript with the PAH and discuss potential applications for the future treatment of some PKU patients.
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Affiliation(s)
- Chunru Lin
- Department of Molecular and Cellular Oncology, Division of Basic Science Research, The University of Texas, MD Anderson Cancer Center, Houston, TX, United States of America
| | - Yajuan Li
- Department of Molecular and Cellular Oncology, Division of Basic Science Research, The University of Texas, MD Anderson Cancer Center, Houston, TX, United States of America
| | - Eric Zhang
- Department of Experimental Therapeutics, The University of Texas, MD Anderson Cancer Center, Houston, TX, United States of America
| | - François Feillet
- INSERM, U1256, NGERE - Nutrition, Genetics, and Environmental Risk Exposure, University of Lorraine, Nancy, France; Pediatric Department Reference Center for Inborn Errors of Metabolism Children University Hospital Nancy, Nancy, France
| | - Shuxing Zhang
- Department of Experimental Therapeutics, The University of Texas, MD Anderson Cancer Center, Houston, TX, United States of America
| | - Nenad Blau
- Division of Metabolism, University Children's Hospital Zürich, Zurich, Switzerland.
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16
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Martín‐Rivada Á, Palomino Pérez L, Ruiz‐Sala P, Navarrete R, Cambra Conejero A, Quijada Fraile P, Moráis López A, Belanger‐Quintana A, Martín‐Hernández E, Bellusci M, Cañedo Villaroya E, Chumillas Calzada S, García Silva MT, Bergua Martínez A, Stanescu S, Martínez‐Pardo Casanova M, Ruano MLF, Ugarte M, Pérez B, Pedrón‐Giner C. Diagnosis of inborn errors of metabolism within the expanded newborn screening in the Madrid region. JIMD Rep 2022; 63:146-161. [PMID: 35281663 PMCID: PMC8898721 DOI: 10.1002/jmd2.12265] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 11/22/2021] [Accepted: 11/23/2021] [Indexed: 12/21/2022] Open
Abstract
We present the results of our experience in the diagnosis of inborn errors of metabolism (IEM) since the Expanded Newborn Screening was implemented in our Region. Dried blood samples were collected 48 h after birth. Amino acids and acylcarnitines were quantitated by mass spectrometry (MS)/MS. Newborns with alterations were referred to the clinical centers for follow‐up. Biochemical and molecular genetic studies for confirmation of a disease were performed. In the period 2011 to 2019, 592 822 children were screened: 902 of them were referred for abnormal results. An IEM was confirmed in 222 (1/2670): aminoacidopathies: 89 hyperphenylalaninemia (HPA) (51 benign HPA, 32 phenylketonuria, 4 DNAJC12 defect, and 2 primapterinuria), 6 hypermethioninemia, 3 tyrosinemia type 1 (TYR‐1), 1 TYR‐3, 4 maple syrup urine disease (MSUD), 2 branched‐chain amino acid transferase 2 deficiency, 2 homocystinuria, 1 cystinuria, 2 ornithine transcarbamylase (OTC) deficiency, 2 citrullinemia type I (CTLN1); FAO defects: 43 medium‐chain acyl‐CoA dehydrogenase deficiency (MCADD), 13 very long‐chain acyl‐CoA dehydrogenase deficiency, 2 long‐chain 3‐hydroxyacyl‐CoA dehydrogenase deficiency (LCHADD), 1 multiple acyl‐coA dehydrogenation deficiency, 11 systemic primary carnitine deficiency, 2 carnitine palmitoyltransferase type 2 (CPT‐II) deficiency, 1 CPT‐I deficiency; organic acidurias: 12 glutaric aciduria type 1 (GA‐1), 4 methylmalonic acidemia (MMA), 7 MMA including combined cases with homocystinuria (MMAHC), 6 propionic acidemia (PA), 7 3‐methylcrotonyl‐CoA carboxylase, 1 3‐hydroxy‐3‐methylglutaryl‐CoA lyase deficiency lyase deficiency. Only 19 infants (8.5%) were symptomatic at newborn screening result (1 LCHADD, 5 PA, 1 CPT‐II deficiency, 1 MMA, 3 MMAHC, 2 MSUD, 2 OTC deficiency, 1 CTLN1, 1 MCADD, 2 TYR‐1). No false negative cases were identified. Genetic diagnosis was conclusive in all biochemically confirmed cases, except for two infants with HPA, identifying pathogenic variants in 32 different genes. The conditions with the highest incidence were HPA (1/6661) and MCAD deficiencies (1/13 787).
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Affiliation(s)
- Álvaro Martín‐Rivada
- Sección de Gastroenterología y Nutrición Hospital Infantil Universitario Niño Jesús Madrid Spain
| | - Laura Palomino Pérez
- Sección de Gastroenterología y Nutrición Hospital Infantil Universitario Niño Jesús Madrid Spain
| | - Pedro Ruiz‐Sala
- Centro de Diagnóstico de Enfermedades Moleculares Universidad Autónoma de Madrid, IdiPAZ, CIBERER Madrid Spain
| | - Rosa Navarrete
- Centro de Diagnóstico de Enfermedades Moleculares Universidad Autónoma de Madrid, IdiPAZ, CIBERER Madrid Spain
| | - Ana Cambra Conejero
- Laboratorio de Cribado Neonatal de la Comunidad de Madrid Servicio de Bioquímica Clínica, Hospital General Universitario Gregorio Marañón Madrid Spain
| | - Pilar Quijada Fraile
- Unidad de Enfermedades Mitocondriales‐Metabólicas Hereditarias Centro de Referencia Nacional (CSUR) y Europeo (MetabERN) en Enfermedades Metabólicas, Hospital Universitario 12 de Octubre Madrid Spain
| | - Ana Moráis López
- Unidad de Nutrición Infantil y Enfermedades Metabólicas Hospital Universitario La Paz Madrid Spain
| | - Amaya Belanger‐Quintana
- Centro de Referencia Nacional (CSUR) en Enfermedades Metabólicas Hospital Universitario Ramón y Cajal Madrid Spain
| | - Elena Martín‐Hernández
- Unidad de Enfermedades Mitocondriales‐Metabólicas Hereditarias Centro de Referencia Nacional (CSUR) y Europeo (MetabERN) en Enfermedades Metabólicas, Hospital Universitario 12 de Octubre Madrid Spain
| | - Marcello Bellusci
- Unidad de Enfermedades Mitocondriales‐Metabólicas Hereditarias Centro de Referencia Nacional (CSUR) y Europeo (MetabERN) en Enfermedades Metabólicas, Hospital Universitario 12 de Octubre Madrid Spain
| | - Elvira Cañedo Villaroya
- Sección de Gastroenterología y Nutrición Hospital Infantil Universitario Niño Jesús Madrid Spain
| | - Silvia Chumillas Calzada
- Unidad de Enfermedades Mitocondriales‐Metabólicas Hereditarias Centro de Referencia Nacional (CSUR) y Europeo (MetabERN) en Enfermedades Metabólicas, Hospital Universitario 12 de Octubre Madrid Spain
| | - María Teresa García Silva
- Unidad de Enfermedades Mitocondriales‐Metabólicas Hereditarias Centro de Referencia Nacional (CSUR) y Europeo (MetabERN) en Enfermedades Metabólicas, Hospital Universitario 12 de Octubre Madrid Spain
| | - Ana Bergua Martínez
- Unidad de Nutrición Infantil y Enfermedades Metabólicas Hospital Universitario La Paz Madrid Spain
| | - Sinziana Stanescu
- Centro de Referencia Nacional (CSUR) en Enfermedades Metabólicas Hospital Universitario Ramón y Cajal Madrid Spain
| | | | - Miguel L. F. Ruano
- Laboratorio de Cribado Neonatal de la Comunidad de Madrid Servicio de Bioquímica Clínica, Hospital General Universitario Gregorio Marañón Madrid Spain
| | - Magdalena Ugarte
- Centro de Diagnóstico de Enfermedades Moleculares Universidad Autónoma de Madrid, IdiPAZ, CIBERER Madrid Spain
| | - Belén Pérez
- Centro de Diagnóstico de Enfermedades Moleculares Universidad Autónoma de Madrid, IdiPAZ, CIBERER Madrid Spain
| | - Consuelo Pedrón‐Giner
- Sección de Gastroenterología y Nutrición Hospital Infantil Universitario Niño Jesús Madrid Spain
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17
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Kaida A, Iwakuma T. Regulation of p53 and Cancer Signaling by Heat Shock Protein 40/J-Domain Protein Family Members. Int J Mol Sci 2021; 22:13527. [PMID: 34948322 PMCID: PMC8706882 DOI: 10.3390/ijms222413527] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 12/13/2021] [Accepted: 12/14/2021] [Indexed: 12/27/2022] Open
Abstract
Heat shock proteins (HSPs) are molecular chaperones that assist diverse cellular activities including protein folding, intracellular transportation, assembly or disassembly of protein complexes, and stabilization or degradation of misfolded or aggregated proteins. HSP40, also known as J-domain proteins (JDPs), is the largest family with over fifty members and contains highly conserved J domains responsible for binding to HSP70 and stimulation of the ATPase activity as a co-chaperone. Tumor suppressor p53 (p53), the most frequently mutated gene in human cancers, is one of the proteins that functionally interact with HSP40/JDPs. The majority of p53 mutations are missense mutations, resulting in acquirement of unexpected oncogenic activities, referred to as gain of function (GOF), in addition to loss of the tumor suppressive function. Moreover, stability and levels of wild-type p53 (wtp53) and mutant p53 (mutp53) are crucial for their tumor suppressive and oncogenic activities, respectively. However, the regulatory mechanisms of wtp53 and mutp53 are not fully understood. Accumulating reports demonstrate regulation of wtp53 and mutp53 levels and/or activities by HSP40/JDPs. Here, we summarize updated knowledge related to the link of HSP40/JDPs with p53 and cancer signaling to improve our understanding of the regulation of tumor suppressive wtp53 and oncogenic mutp53 GOF activities.
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Affiliation(s)
- Atsushi Kaida
- Department of Oral Radiation Oncology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo 113-8510, Japan;
- Department of Cancer Biology, University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Tomoo Iwakuma
- Department of Cancer Biology, University of Kansas Medical Center, Kansas City, KS 66160, USA
- Department of Pediatrics, Children’s Mercy Research Institute, Kansas City, MO 64108, USA
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18
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Çıkı K, Yıldız Y, Yücel Yılmaz D, Pektaş E, Tokatlı A, Özgül RK, Sivri HS, Dursun A. DNACJ12 deficiency in patients with unexplained hyperphenylalaninemia: two new patients and a novel variant. Metab Brain Dis 2021; 36:1405-1410. [PMID: 34014443 DOI: 10.1007/s11011-021-00753-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 05/10/2021] [Indexed: 10/21/2022]
Abstract
In addition to tetrahydrobiopterin deficiencies and phenylalanine hydroxylase deficiency (phenylketonuria) due to PAH variants, the deficiency of the co-chaperone protein DNAJC12 was identified in 2017 as a novel cause of inherited hyperphenylalaninemia, revealing the genetic etiology in previously unresolved cases. In this study, we aimed to investigate DNAJC12 deficiency in non-tetrahydrobiopterin-deficient persistent hyperphenylalaninemia cases without biallelic PAH variants in a single pediatric metabolic center. It was determined retrospectively that 471 patients with non-tetrahydrobiopterin deficiency-hyperphenylalaninemia had undergone PAH gene sequencing and 451 patients had biallelic variants in PAH. DNAJC12 sequencing was performed in the remaining 20 patients, identifying a previously reported homozygous splice-site variant (c.158-2A > T) in one patient with axial hypotonia and developmental delay, and a novel, homozygous c.404del (p.Arg135Lysfs*21) frameshift variant in an asymptomatic patient. In segregation analysis, the asymptomatic patient's both parents were also found to be homozygous for this variant and hyperphenylalaninemic. The parents may have had academic difficulties but intellectual disability could not be confirmed due to lack of cooperation. The symptomatic patient significantly benefited from treatment with sapropterin dihydrochloride and neurotransmitter precursors. DNAJC12 deficiency might be responsible for approximately 10% or more of cases with unexplained hyperphenylalaninemia. The phenotypic spectrum is broad, ranging from early infantile hypotonia to incidental diagnosis in adulthood. Similar to tetrahydrobiopterin deficiencies, early diagnosis and treatment with sapropterin dihydrochloride and neurotransmitter precursors can be beneficial, supporting the analysis of DNACJ12 gene in patients with unexplained hyperphenylalaninemia.
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Affiliation(s)
- Kısmet Çıkı
- Division of Pediatric Metabolism, Department of Pediatrics, Faculty of Medicine, Hacettepe University, Ankara, Turkey.
| | - Yılmaz Yıldız
- Division of Pediatric Metabolism, Department of Pediatrics, Faculty of Medicine, Hacettepe University, Ankara, Turkey
| | - Didem Yücel Yılmaz
- Department of Pediatric Metabolism, Institute of Child Health, Hacettepe University, Ankara, Turkey
| | - Emine Pektaş
- Pediatric Metabolic Diseases Unit, Gaziantep Cengiz Gökçek Maternity and Pediatrics Hospital, Gaziantep, Turkey
| | - Ayşegül Tokatlı
- Division of Pediatric Metabolism, Department of Pediatrics, Faculty of Medicine, Hacettepe University, Ankara, Turkey
| | - R Köksal Özgül
- Department of Pediatric Metabolism, Institute of Child Health, Hacettepe University, Ankara, Turkey
| | - H Serap Sivri
- Division of Pediatric Metabolism, Department of Pediatrics, Faculty of Medicine, Hacettepe University, Ankara, Turkey
| | - Ali Dursun
- Division of Pediatric Metabolism, Department of Pediatrics, Faculty of Medicine, Hacettepe University, Ankara, Turkey
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Li Y, Li M, Jin F, Liu J, Chen M, Yin J. DNAJC12 promotes lung cancer growth by regulating the activation of β‑catenin. Int J Mol Med 2021; 47:105. [PMID: 33907820 PMCID: PMC8057298 DOI: 10.3892/ijmm.2021.4938] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 03/24/2021] [Indexed: 01/03/2023] Open
Abstract
Lung cancer has become the leading cause of cancer‑associated mortality worldwide. However, the underlying mechanisms of lung cancer remain poorly understood. DnaJ heat shock protein family (HSP40) member C12 (DNAJC12) is a type III member belonging to the HSP40/DNAJ family. The role of DNAJC12 in numerous types of cancer has been previously reported; however, the effect of DNAJC12 in lung cancer remains unknown. The results of the present study indicated that DNAJC12 may be involved in lung cancer proliferation and migration by regulating the β‑catenin signaling pathway. Data generated in the present study and from The Cancer Genome Atlas revealed that the DNAJC12 expression levels were significantly upregulated in lung cancer tissues compared with non‑cancer lung tissues. The expression of DNAJC12 was subsequently knocked down in A549 and NCI‑H1975 lung cancer cells using lentiviral transfections and further experiments demonstrated that the knockdown of DNAJC12 inhibited the proliferation, colony formation, migration and invasion of lung cancer cells. The results of flow cytometric assays also revealed that the knockdown of DNAJC12 induced the apoptosis of lung cancer cells. In addition, the effects of DNAJC12 knockdown on the in vivo growth of lung cancer cells were observed. Signaling pathway analysis revealed that the knockdown of DNAJC12 expression suppressed the phosphorylation of p65 NF‑κB, downregulated the expression levels and inhibited the subsequent activation of β‑catenin, and downregulated the expression levels of vimentin. Rescue experiments demonstrated that the overexpression of β‑catenin, but not that of NF‑κB or vimentin, reversed the effects of DNAJC12 knockdown on the proliferation and invasion of lung cancer cells. On the whole, the findings of the present study suggest that DNAJC12 may play a crucial role in lung cancer tumorigenesis by regulating the expression and activation of β‑catenin. Therefore, DNAJC12 may represent a novel target for the treatment of lung cancer.
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Affiliation(s)
- Yun Li
- School of Medicine, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250012, P.R. China
- Department of Thoracic Surgery, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250021, P.R. China
| | - Meng Li
- Department of Thoracic Surgery, The First People's Hospital of Taian Affiliated to Shandong First Medical University, Taian, Shandong 271000, P.R. China
| | - Fengqi Jin
- Department of Thoracic Surgery, Jinan Zhangqiu District Hospital of Traditional Chinese Medicine, Jinan, Shandong 250200, P.R. China
| | - Jianbo Liu
- Department of Thoracic Surgery, The Fourth People's Hospital, Heze, Shangdong 274100, P.R. China
| | - Minghui Chen
- Department of Anesthesia Surgery, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong 271000, P.R. China
| | - Jingjing Yin
- Department of Thoracic Surgery, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong 250021, P.R. China
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20
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Gundorova P, Kuznetcova IA, Baydakova GV, Stepanova AA, Itkis YS, Kakaulina VS, Alferova IP, Lyazina LV, Andreeva LP, Kanivets I, Zakharova EY, Kutsev SI, Polyakov AV. BH4-deficient hyperphenylalaninemia in Russia. PLoS One 2021; 16:e0249608. [PMID: 33822819 PMCID: PMC8023510 DOI: 10.1371/journal.pone.0249608] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 03/22/2021] [Indexed: 02/07/2023] Open
Abstract
A timely detection of patients with tetrahydrobiopterin (BH4) -deficient types of hyperphenylalaninemia (HPABH4) is important for assignment of correct therapy, allowing to avoid complications. Often HPABH4 patients receive the same therapy as phenylalanine hydroxylase (PAH) -deficiency (phenylketonuria) patients—dietary treatment—and do not receive substitutive BH4 therapy until the diagnosis is confirmed by molecular genetic means. In this study, we present a cohort of 30 Russian patients with HPABH4 with detected variants in genes causing different types of HPA. Family diagnostics and biochemical urinary pterin spectrum analyses were carried out. HPABH4A is shown to be the prevalent type, 83.3% of all HPABH4 cases. The mutation spectrum for the PTS gene was defined, the most common variants in Russia were p.Thr106Met—32%, p.Asn72Lys—20%, p.Arg9His—8%, p.Ser32Gly—6%. We also detected 7 novel PTS variants and 3 novel QDPR variants. HPABH4 prevalence was estimated to be 0.5–0.9% of all HPA cases in Russia, which is significantly lower than in European countries on average, China, and Saudi Arabia. The results of this research show the necessity of introducing differential diagnostics for HPABH4 into neonatal screening practice.
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Affiliation(s)
| | | | | | | | | | - Victoria S. Kakaulina
- Federal State Budgetary Institution of Medical Department of Moscow “Morozov Children’s City Clinical Hospital of Medical Department of Moscow”, Moscow, Russia
| | - Irina P. Alferova
- Municipal Autonomous Health Care Institution of the Order of the Red Banner of Labor “Clinical Hospital № 1”, Chelyabinsk, Russia
| | - Lidya V. Lyazina
- Saint Petersburg State Public Health Institution "Medical Genetic Diagnostic Center”, Saint Petersburg, Russia
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21
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Tyagi A, Sarodaya N, Kaushal K, Chandrasekaran AP, Antao AM, Suresh B, Rhie BH, Kim KS, Ramakrishna S. E3 Ubiquitin Ligase APC/C Cdh1 Regulation of Phenylalanine Hydroxylase Stability and Function. Int J Mol Sci 2020; 21:E9076. [PMID: 33260674 PMCID: PMC7729981 DOI: 10.3390/ijms21239076] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 11/18/2020] [Accepted: 11/25/2020] [Indexed: 12/20/2022] Open
Abstract
Phenylketonuria (PKU) is an autosomal recessive metabolic disorder caused by the dysfunction of the enzyme phenylalanine hydroxylase (PAH). Alterations in the level of PAH leads to the toxic accumulation of phenylalanine in the blood and brain. Protein degradation mediated by ubiquitination is a principal cellular process for maintaining protein homeostasis. Therefore, it is important to identify the E3 ligases responsible for PAH turnover and proteostasis. Here, we report that anaphase-promoting complex/cyclosome-Cdh1 (APC/C)Cdh1 is an E3 ubiquitin ligase complex that interacts and promotes the polyubiquitination of PAH through the 26S proteasomal pathway. Cdh1 destabilizes and declines the half-life of PAH. In contrast, the CRISPR/Cas9-mediated knockout of Cdh1 stabilizes PAH expression and enhances phenylalanine metabolism. Additionally, our current study demonstrates the clinical relevance of PAH and Cdh1 correlation in hepatocellular carcinoma (HCC). Overall, we show that PAH is a prognostic marker for HCC and Cdh1 could be a potential therapeutic target to regulate PAH-mediated physiological and metabolic disorders.
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Affiliation(s)
- Apoorvi Tyagi
- Department of Biomedical Science, Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Korea; (A.T.); (N.S.); (K.K.); (A.P.C.); (A.M.A.); ( (B.S.); (B.H.R.)
| | - Neha Sarodaya
- Department of Biomedical Science, Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Korea; (A.T.); (N.S.); (K.K.); (A.P.C.); (A.M.A.); ( (B.S.); (B.H.R.)
| | - Kamini Kaushal
- Department of Biomedical Science, Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Korea; (A.T.); (N.S.); (K.K.); (A.P.C.); (A.M.A.); ( (B.S.); (B.H.R.)
| | - Arun Pandian Chandrasekaran
- Department of Biomedical Science, Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Korea; (A.T.); (N.S.); (K.K.); (A.P.C.); (A.M.A.); ( (B.S.); (B.H.R.)
| | - Ainsley Mike Antao
- Department of Biomedical Science, Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Korea; (A.T.); (N.S.); (K.K.); (A.P.C.); (A.M.A.); ( (B.S.); (B.H.R.)
| | - Bharathi Suresh
- Department of Biomedical Science, Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Korea; (A.T.); (N.S.); (K.K.); (A.P.C.); (A.M.A.); ( (B.S.); (B.H.R.)
| | - Byung Ho Rhie
- Department of Biomedical Science, Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Korea; (A.T.); (N.S.); (K.K.); (A.P.C.); (A.M.A.); ( (B.S.); (B.H.R.)
| | - Kye Seong Kim
- Department of Biomedical Science, Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Korea; (A.T.); (N.S.); (K.K.); (A.P.C.); (A.M.A.); ( (B.S.); (B.H.R.)
- College of Medicine, Hanyang University, Seoul 04763, Korea
| | - Suresh Ramakrishna
- Department of Biomedical Science, Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Korea; (A.T.); (N.S.); (K.K.); (A.P.C.); (A.M.A.); ( (B.S.); (B.H.R.)
- College of Medicine, Hanyang University, Seoul 04763, Korea
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22
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Sarodaya N, Suresh B, Kim KS, Ramakrishna S. Protein Degradation and the Pathologic Basis of Phenylketonuria and Hereditary Tyrosinemia. Int J Mol Sci 2020; 21:ijms21144996. [PMID: 32679806 PMCID: PMC7404301 DOI: 10.3390/ijms21144996] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 07/10/2020] [Accepted: 07/13/2020] [Indexed: 12/15/2022] Open
Abstract
A delicate intracellular balance among protein synthesis, folding, and degradation is essential to maintaining protein homeostasis or proteostasis, and it is challenged by genetic and environmental factors. Molecular chaperones and the ubiquitin proteasome system (UPS) play a vital role in proteostasis for normal cellular function. As part of protein quality control, molecular chaperones recognize misfolded proteins and assist in their refolding. Proteins that are beyond repair or refolding undergo degradation, which is largely mediated by the UPS. The importance of protein quality control is becoming ever clearer, but it can also be a disease-causing mechanism. Diseases such as phenylketonuria (PKU) and hereditary tyrosinemia-I (HT1) are caused due to mutations in PAH and FAH gene, resulting in reduced protein stability, misfolding, accelerated degradation, and deficiency in functional proteins. Misfolded or partially unfolded proteins do not necessarily lose their functional activity completely. Thus, partially functional proteins can be rescued from degradation by molecular chaperones and deubiquitinating enzymes (DUBs). Deubiquitination is an important mechanism of the UPS that can reverse the degradation of a substrate protein by covalently removing its attached ubiquitin molecule. In this review, we discuss the importance of molecular chaperones and DUBs in reducing the severity of PKU and HT1 by stabilizing and rescuing mutant proteins.
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Affiliation(s)
- Neha Sarodaya
- Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Korea; (N.S.); (B.S.)
| | - Bharathi Suresh
- Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Korea; (N.S.); (B.S.)
| | - Kye-Seong Kim
- Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Korea; (N.S.); (B.S.)
- College of Medicine, Hanyang University, Seoul 04763, Korea
- Correspondence: (K.-S.K.); or (S.R.)
| | - Suresh Ramakrishna
- Graduate School of Biomedical Science and Engineering, Hanyang University, Seoul 04763, Korea; (N.S.); (B.S.)
- College of Medicine, Hanyang University, Seoul 04763, Korea
- Correspondence: (K.-S.K.); or (S.R.)
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