PUBLICATION

Functional validation of novel MKS3/TMEM67 mutations in COACH syndrome

Authors
Lee, S.H., Nam, T.S., Li, W., Kim, J.H., Yoon, W., Choi, Y.D., Kim, K.H., Cai, H., Kim, M.J., Kim, C., Choy, H.E., Kim, N., Chay, K.O., Kim, M.K., Choi, S.Y.
ID
ZDB-PUB-170902-2
Date
2017
Source
Scientific Reports   7: 10222 (Journal)
Registered Authors
Choi, Seok-Yong, Kim, Min Jung, Lee, So-Hyun, Li, Wenting
Keywords
Developmental disorders, Genetics research, Neurodevelopmental disorders
MeSH Terms
  • Abnormalities, Multiple/drug therapy
  • Abnormalities, Multiple/genetics*
  • Abnormalities, Multiple/metabolism
  • Animals
  • Ataxia/drug therapy
  • Ataxia/genetics*
  • Ataxia/metabolism
  • Brain/abnormalities*
  • Brain/metabolism
  • Cholestasis/drug therapy
  • Cholestasis/genetics*
  • Cholestasis/metabolism
  • Coloboma/drug therapy
  • Coloboma/genetics*
  • Coloboma/metabolism
  • Disease Models, Animal
  • HEK293 Cells
  • Humans
  • Liver Diseases/drug therapy
  • Liver Diseases/genetics*
  • Liver Diseases/metabolism
  • Male
  • Membrane Proteins/genetics*
  • Membrane Proteins/metabolism*
  • Morpholinos/administration & dosage
  • Morpholinos/pharmacology
  • Mutation*
  • Mutation, Missense
  • Sequence Deletion
  • Wnt Signaling Pathway
  • Young Adult
  • Zebrafish
PubMed
28860541 Full text @ Sci. Rep.
Abstract
COACH syndrome is an autosomal recessive developmental disorder, a subtype of Joubert syndrome and related disorders, characterized by cerebellar vermis hypoplasia, oligophrenia, ataxia, coloboma, and hepatic fibrosis. Although mutations in TMEM67 (transmembrane protein 67)/MKS3 (Meckel-Gruber syndrome, type 3) were reported to cause COACH syndrome, this causality has not verified by functional studies. In a 20-year-old Korean man, we found cerebellar ataxia, isolated elevation in serum γ-glutamyl transpeptidase (γ-GTP) activity, oligophrenia, the molar tooth sign (MTS) in the brain MR images and congenital hepatic fibrosis (CHF). Two novel compound heterozygous mutations were found in TMEM67 in the patient: i) missense mutation (c.395 G > C and p.Gly132Ala) in exon 3, and ii) deletion in exon 26 (c.2758delT and p.Tyr920ThrfsX40). Western blotting showed that the p.Tyr920ThrfsX40 mutation accelerates turnover of the TMEM67 protein. Although wild-type human TMEM67 RNA rescued phenotypes of zebrafish embryos injected with anti-sense oligonucleotide morpholinos against tmem67, the two human TMEM67 RNAs individually harboring the two mutations did not. Finally, Wnt signaling, but not Hedgehog signaling, was suppressed in tmem67 morphants. To the best of our knowledge, this is the first report verifying the causality between COACH syndrome and TMEM67, which will further our understanding of molecular pathogenesis of the syndrome.
Genes / Markers
Figures
Show all Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping