title: The dual targeting ability of type II NAD(P)H dehydrogenases arose early in land plant evolution.
abstract: BACKGROUND
  Type II NAD(PH) dehydrogenases are located on the inner mitochondrial membrane of plants, fungi, protists and some primitive animals. However, recent observations have been made which identify several Arabidopsis type II dehydrogenases as dual targeted proteins. Targeting either mitochondria and peroxisomes or mitochondria and chloroplasts.
  
  
  RESULTS
  Members of the ND protein family were identified in various plant species. Phylogenetic analyses and subcellular targeting predictions were carried out for all proteins. All ND proteins from three model plant species Arabidopsis, rice and Physcomitrella were cloned as N- and C-terminal GFP fusions and subcellular localisations were determined. Dual targeting of plant type II dehydrogenases was observed to have evolved early in plant evolution and to be widespread throughout different plant species. In all three species tested dual targeting to both mitochondria and peroxisomes was found for at least one NDA and NDB type protein. In addition two NDB type proteins from Physcomitrella were also found to target chloroplasts. The dual targeting of NDC type proteins was found to have evolved later in plant evolution.
  
  
  CONCLUSIONS
  The functions of type II dehydrogenases within plant cells will have to be re-evaluated in light of this newly identified subcellular targeting information.
authors.affiliation: ARC Centre of Excellence in Plant Energy Biology, Bayliss Building M316, University of Western Australia, 35 Stirling Highway, Crawley 6009, Western Australia.
authors.forename: Lin
authors.initials: L
authors.lastname: Xu
authors.forename: Simon R
authors.initials: SR
authors.lastname: Law
authors.forename: Monika W
authors.initials: MW
authors.lastname: Murcha
authors.forename: James
authors.initials: J
authors.lastname: Whelan
authors.forename: Chris
authors.initials: C
authors.lastname: Carrie
mesh_terms: D000595:Amino Acid Sequence; D019669:Embryophyta / Q000145:classification / Q000201:enzymology* / Q000235:genetics; D019143:Evolution, Molecular; D008969:Molecular Sequence Data; D009243:NAD / Q000378:metabolism; D009249:NADP / Q000378:metabolism; D010088:Oxidoreductases / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D021381:Protein Transport
chemical_list: D010940:Plant Proteins; D009243:NAD; D009249:NADP; D010088:Oxidoreductases