title: Structural and functional consequences of succinate dehydrogenase subunit B mutations.
abstract: Mitochondrial dysfunction, due to mutations of the gene encoding succinate dehydrogenase (SDH), has been implicated in the development of adrenal phaeochromocytomas, sympathetic and parasympathetic paragangliomas, renal cell carcinomas, gastrointestinal stromal tumours and more recently pituitary tumours. Underlying mechanisms behind germline SDH subunit B (SDHB) mutations and their associated risk of disease are not clear. To investigate genotype-phenotype correlation of SDH subunit B (SDHB) variants, a homology model for human SDH was developed from a crystallographic structure. SDHB mutations were mapped, and biochemical effects of these mutations were predicted in silico. Results of structural modelling indicated that many mutations within SDHB are predicted to cause either failure of functional SDHB expression (p.Arg27*, p.Arg90*, c.88delC and c.311delAinsGG), or disruption of the electron path (p.Cys101Tyr, p.Pro197Arg and p.Arg242His). GFP-tagged WT SDHB and mutant SDHB constructs were transfected (HEK293) to determine biological outcomes of these mutants in vitro. According to in silico predictions, specific SDHB mutations resulted in impaired mitochondrial localisation and/or SDH enzymatic activity. These results indicated strong genotype-functional correlation for SDHB variants. This study reveals new insights into the effects of SDHB mutations and the power of structural modelling in predicting biological consequences. We predict that our functional assessment of SDHB mutations will serve to better define specific consequences for SDH activity as well as to provide a much needed assay to distinguish pathogenic mutations from benign variants.
authors.affiliation: Cancer GeneticsKolling Institute of Medical Research, Royal North Shore Hospital, and University of Sydney, Sydney, New South Wales, AustraliaDepartment of EndocrinologyRoyal North Shore Hospital, Sydney, New South Wales, AustraliaFaculty of PharmacyUniversity of Sydney, Sydney, New South Wales, AustraliaAustralian Nuclear Science and Technology OrganisationLucas Heights, New South Wales, Australia edward.kim@sydney.edu.au.
authors.forename: E
authors.initials: E
authors.lastname: Kim
authors.affiliation: Cancer GeneticsKolling Institute of Medical Research, Royal North Shore Hospital, and University of Sydney, Sydney, New South Wales, AustraliaDepartment of EndocrinologyRoyal North Shore Hospital, Sydney, New South Wales, AustraliaFaculty of PharmacyUniversity of Sydney, Sydney, New South Wales, AustraliaAustralian Nuclear Science and Technology OrganisationLucas Heights, New South Wales, Australia.
authors.forename: E M
authors.initials: EM
authors.lastname: Rath
authors.affiliation: Cancer GeneticsKolling Institute of Medical Research, Royal North Shore Hospital, and University of Sydney, Sydney, New South Wales, AustraliaDepartment of EndocrinologyRoyal North Shore Hospital, Sydney, New South Wales, AustraliaFaculty of PharmacyUniversity of Sydney, Sydney, New South Wales, AustraliaAustralian Nuclear Science and Technology OrganisationLucas Heights, New South Wales, Australia Cancer GeneticsKolling Institute of Medical Research, Royal North Shore Hospital, and University of Sydney, Sydney, New South Wales, AustraliaDepartment of EndocrinologyRoyal North Shore Hospital, Sydney, New South Wales, AustraliaFaculty of PharmacyUniversity of Sydney, Sydney, New South Wales, AustraliaAustralian Nuclear Science and Technology OrganisationLucas Heights, New South Wales, Australia.
authors.forename: V H M
authors.initials: VH
authors.lastname: Tsang
authors.affiliation: Cancer GeneticsKolling Institute of Medical Research, Royal North Shore Hospital, and University of Sydney, Sydney, New South Wales, AustraliaDepartment of EndocrinologyRoyal North Shore Hospital, Sydney, New South Wales, AustraliaFaculty of PharmacyUniversity of Sydney, Sydney, New South Wales, AustraliaAustralian Nuclear Science and Technology OrganisationLucas Heights, New South Wales, Australia.
authors.forename: A P
authors.initials: AP
authors.lastname: Duff
authors.affiliation: Cancer GeneticsKolling Institute of Medical Research, Royal North Shore Hospital, and University of Sydney, Sydney, New South Wales, AustraliaDepartment of EndocrinologyRoyal North Shore Hospital, Sydney, New South Wales, AustraliaFaculty of PharmacyUniversity of Sydney, Sydney, New South Wales, AustraliaAustralian Nuclear Science and Technology OrganisationLucas Heights, New South Wales, Australia Cancer GeneticsKolling Institute of Medical Research, Royal North Shore Hospital, and University of Sydney, Sydney, New South Wales, AustraliaDepartment of EndocrinologyRoyal North Shore Hospital, Sydney, New South Wales, AustraliaFaculty of PharmacyUniversity of Sydney, Sydney, New South Wales, AustraliaAustralian Nuclear Science and Technology OrganisationLucas Heights, New South Wales, Australia.
authors.forename: B G
authors.initials: BG
authors.lastname: Robinson
authors.affiliation: Cancer GeneticsKolling Institute of Medical Research, Royal North Shore Hospital, and University of Sydney, Sydney, New South Wales, AustraliaDepartment of EndocrinologyRoyal North Shore Hospital, Sydney, New South Wales, AustraliaFaculty of PharmacyUniversity of Sydney, Sydney, New South Wales, AustraliaAustralian Nuclear Science and Technology OrganisationLucas Heights, New South Wales, Australia.
authors.forename: W B
authors.initials: WB
authors.lastname: Church
authors.affiliation: Cancer GeneticsKolling Institute of Medical Research, Royal North Shore Hospital, and University of Sydney, Sydney, New South Wales, AustraliaDepartment of EndocrinologyRoyal North Shore Hospital, Sydney, New South Wales, AustraliaFaculty of PharmacyUniversity of Sydney, Sydney, New South Wales, AustraliaAustralian Nuclear Science and Technology OrganisationLucas Heights, New South Wales, Australia.
authors.forename: D E
authors.initials: DE
authors.lastname: Benn
authors.affiliation: Cancer GeneticsKolling Institute of Medical Research, Royal North Shore Hospital, and University of Sydney, Sydney, New South Wales, AustraliaDepartment of EndocrinologyRoyal North Shore Hospital, Sydney, New South Wales, AustraliaFaculty of PharmacyUniversity of Sydney, Sydney, New South Wales, AustraliaAustralian Nuclear Science and Technology OrganisationLucas Heights, New South Wales, Australia.
authors.forename: T
authors.initials: T
authors.lastname: Dwight
authors.affiliation: Cancer GeneticsKolling Institute of Medical Research, Royal North Shore Hospital, and University of Sydney, Sydney, New South Wales, AustraliaDepartment of EndocrinologyRoyal North Shore Hospital, Sydney, New South Wales, AustraliaFaculty of PharmacyUniversity of Sydney, Sydney, New South Wales, AustraliaAustralian Nuclear Science and Technology OrganisationLucas Heights, New South Wales, Australia Cancer GeneticsKolling Institute of Medical Research, Royal North Shore Hospital, and University of Sydney, Sydney, New South Wales, AustraliaDepartment of EndocrinologyRoyal North Shore Hospital, Sydney, New South Wales, AustraliaFaculty of PharmacyUniversity of Sydney, Sydney, New South Wales, AustraliaAustralian Nuclear Science and Technology OrganisationLucas Heights, New South Wales, Australia.
authors.forename: R J
authors.initials: RJ
authors.lastname: Clifton-Bligh
mesh_terms: D000310:Adrenal Gland Neoplasms / Q000201:enzymology* / Q000235:genetics; D018929:Cell Culture Techniques; D020022:Genetic Predisposition to Disease; D057809:HEK293 Cells; D006801:Humans; D008928:Mitochondria / Q000201:enzymology / Q000473:pathology; D008958:Models, Molecular; D009154:Mutation; D010235:Paraganglioma / Q000201:enzymology* / Q000235:genetics; D010673:Pheochromocytoma / Q000201:enzymology* / Q000235:genetics; D017433:Protein Structure, Secondary; D013385:Succinate Dehydrogenase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D014162:Transfection
chemical_list: C108095:SDHB protein, human; D013385:Succinate Dehydrogenase
keywords: SDHB; functional consequences; paraganglioma; phaeochromocytoma; succinate dehydrogenase