The C-type Arabidopsis thioredoxin reductase ANTR-C acts as an electron donor to 2-Cys peroxiredoxins in chloroplasts.
2-Cys peroxiredoxins (Prxs) play important roles in the antioxidative defense systems of plant chloroplasts. In order to determine the interaction partner for these proteins in Arabidopsis, we used a yeast two-hybrid screening procedure with a C175S-mutant of Arabidopsis 2-Cys Prx-A as bait. A cDNA encoding an NADPH-dependent thioredoxin reductase (NTR) isotype C was identified and designated ANTR-C. We demonstrated that this protein effected efficient transfer of electrons from NADPH to the 2-Cys Prxs of chloroplasts. Interaction between 2-Cys Prx-A and ANTR-C was confirmed by a pull-down experiment. ANTR-C contained N-terminal TR and C-terminal Trx domains. It exhibited both TR and Trx activities and co-localized with 2-Cys Prx-A in chloroplasts. These results suggest that ANTR-C functions as an electron donor for plastidial 2-Cys Prxs and represents the NADPH-dependent TR/Trx system in chloroplasts.
Moon
Jeong Chan
JC
Environmental Biotechnology National Core Research Center, Gyeongsang National University, Jinju 660-701, Republic of Korea.
Jang
Ho Hee
HH
Chae
Ho Byoung
HB
Lee
Jung Ro
JR
Lee
Sun Yong
SY
Jung
Young Jun
YJ
Shin
Mi Rim
MR
Lim
Hye Song
HS
Chung
Woo Sik
WS
Yun
Dae-Jin
DJ
Lee
Kyun Oh
KO
Lee
Sang Yeol
SY
D017360:Arabidopsis / Q000201:enzymology; D029681:Arabidopsis Proteins / Q000378:metabolism*; D002736:Chloroplasts / Q000201:enzymology; D004583:Electrons; D009249:NADP / Q000378:metabolism; D010544:Peroxidases / Q000378:metabolism*; D054464:Peroxiredoxins; D013880:Thioredoxin-Disulfide Reductase / Q000378:metabolism*
D029681:Arabidopsis Proteins; D009249:NADP; D010544:Peroxidases; C493631:2-Cys peroxiredoxin A, Arabidopsis; D054464:Peroxiredoxins; C514013:ANTR-C protein, Arabidopsis; D013880:Thioredoxin-Disulfide Reductase