title: A novel isoform of the human mitochondrial complex I subunit NDUFV3.
abstract: Human mitochondrial complex I is the first enzyme of the mitochondrial respiratory chain. Complex I is composed of 45 subunits, seven encoded by mitochondrial DNA, while the remainder are encoded by nuclear DNA. All nuclear-encoded subunits are thought to be expressed as a single isoform. Here we reveal subunit NDUFV3 to be present in both the canonical 10 kDa and a novel 50 kDa isoform, generated through alternative splicing. Both isoforms assemble into complex I and their levels vary in different tissues. While the 50 kDa isoform appears to be dominant in HEK293T cells, we find either isoform alone is sufficient for assembly of mature complex I. NDUFV3 represents the first known complex I subunit present in two functional isoforms.
authors.affiliation: Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Melbourne, Australia.
authors.forename: Marris G
authors.initials: MG
authors.lastname: Dibley
authors.affiliation: Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Melbourne, Australia.
authors.forename: Michael T
authors.initials: MT
authors.lastname: Ryan
authors.affiliation: Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, Melbourne, Australia.
authors.forename: David A
authors.identifier: http://orcid.org/0000-0002-2048-3383
authors.initials: DA
authors.lastname: Stroud
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D042967:Electron Transport Complex I / Q000737:chemistry / Q000378:metabolism*; D059472:Exome / Q000235:genetics; D057809:HEK293 Cells; D006720:Homozygote; D006801:Humans; D008810:Mice, Inbred C57BL; D008928:Mitochondria / Q000378:metabolism; D009154:Mutation / Q000235:genetics; D009245:NADH Dehydrogenase / Q000737:chemistry / Q000378:metabolism*; D020033:Protein Isoforms / Q000737:chemistry / Q000378:metabolism; D021122:Protein Subunits / Q000737:chemistry / Q000378:metabolism*
chemical_list: C000619120:NDUFV3 protein, human; D020033:Protein Isoforms; D021122:Protein Subunits; D009245:NADH Dehydrogenase; D042967:Electron Transport Complex I
keywords: 
  OXPHOS
  ; NADH dehydrogenase; complex I; metabolism; mitochondria