title: Homozygous Gly555Glu mutation in the nuclear-encoded 70 kDa flavoprotein gene causes instability of the respiratory chain complex II.
abstract: A homozygous mutation in the flavoprotein (Fp) gene associated with complex II deficiency was demonstrated in a patient with consanguineous parents. She succumbed at 5(1/2) months of age following a respiratory infection. The c1664G-->A transition detected, predicted the substitution of the small uncharged glycine at position 555 by glutamic acid. Her clinical course was at variance with the Leigh syndrome in three previously reported patients due to Fp gene mutations. In this proband, CRM for flavoprotein as well as iron-containing protein (Ip) was decreased, CRM for the entire complex II (130 kDa) being reduced even more. This observation prompts speculation of a labile interaction between Ip and Fp polypeptides and of a key role of the amino acid at position 555 in the interacting domain.
authors.affiliation: Department of Pediatrics, Division of Pediatric Neurology and Metabolism, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium. rudy.vancoster@rug.ac.be
authors.forename: Rudy
authors.initials: R
authors.lastname: Van Coster
authors.forename: S
authors.initials: S
authors.lastname: Seneca
authors.forename: J
authors.initials: J
authors.lastname: Smet
authors.forename: R
authors.initials: R
authors.lastname: Van Hecke
authors.forename: E
authors.initials: E
authors.lastname: Gerlo
authors.forename: B
authors.initials: B
authors.lastname: Devreese
authors.forename: J
authors.initials: J
authors.lastname: Van Beeumen
authors.forename: J G
authors.initials: JG
authors.lastname: Leroy
authors.forename: L
authors.initials: L
authors.lastname: De Meirleir
authors.forename: W
authors.initials: W
authors.lastname: Lissens
mesh_terms: D000596:Amino Acids / Q000737:chemistry; D006332:Cardiomegaly / Q000235:genetics; D002467:Cell Nucleus / Q000378:metabolism*; D004579:Electron Transport / Q000235:genetics*; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D005347:Fibroblasts / Q000378:metabolism; D005420:Flavoproteins / Q000235:genetics*; D018698:Glutamic Acid / Q000235:genetics; D005973:Glutamine / Q000737:chemistry*; D005998:Glycine / Q000737:chemistry* / Q000235:genetics; D006720:Homozygote; D006801:Humans; D007223:Infant; D007501:Iron / Q000737:chemistry; D008958:Models, Molecular; D018482:Muscle, Skeletal / Q000378:metabolism; D009154:Mutation; D010100:Oxygen / Q000378:metabolism; D010455:Peptides / Q000737:chemistry; D010766:Phosphorylation; D017434:Protein Structure, Tertiary
chemical_list: D000596:Amino Acids; D005420:Flavoproteins; D010455:Peptides; D005973:Glutamine; D018698:Glutamic Acid; D007501:Iron; D010100:Oxygen; D005998:Glycine