Poster: Seed biology

Abs # 714: Functional analyses of FePer1, the 1-Cys peroxiredoxin in buckwheat (Fagopyrum esculentum Moench).

Presenter:	Ueda, Takashi , tueda@fgcu.edu
Authors	Ueda, Takashi  (A)   Harrell, Thomas J. (A)   Wells, Tamara  (A)   Infantado, Nina  (A)   Ellis, Tina  (A)   Compere, Rosenick  (A)   Takenaka, Kazumi  (A)
Affiliations:	(A): Florida Gulf Coast University

A cDNA corresponding to 1-Cys peroxiredoxin, a thiol-specific antioxidant enzyme evolutionarily conserved from bacteria to plants and humans, was isolated from buckwheat (Fagopyrum esculentum Moench). The cDNA, we have designated as FePer1, contains a major open reading frame capable of encoding a polypeptide of 219 residues with a predicted molecular mass of 24.3 kDa. As for all 1-Cys peroxiredoxins identified from various organisms, the amino acid sequence proposed to constitute the active site of the enzyme is highly conserved in FePer1 polypeptide. The gene corresponding to FePer1 cDNA is a single-copy gene in the buckwheat genome. Its expression is regulated in a seed-specific and temporal manner during seed development, it is also induced transiently for a short period immediately after seed imbibition. Expression of FePer1 gene in Escherichia coli confers the bacteria a significant level of tolerance to growth inhibition by the alkyl cumene hydroperoxide. The bacterially expressed recombinant FePer1 protein protects plasmid DNA against cleavage by free radical attack in vitro in a mixed function oxidation system. The genomic clones corresponding to the FePer1 cDNA were isolated. Preliminary results from the transgenic studies focusing on the promoter function and the ectopic expression of FePer1 enzyme in a heterologous plant species are presented.