Imazethapyr enantioselectively affects chlorophyll synthesis and photosynthesis in Arabidopsis thaliana.
Imazethapyr (IM) is a chiral herbicide with reported enantioselective biological activities between its enantiomers. This report investigated the effect of enantioselectivity between R- and S-IM in  Arabidopsis thaliana  on chlorophyll synthesis and photosynthesis. The results suggest that R-IM inhibited the transcription of chlM to a greater extent than S-IM, which reduced chlorophyll synthesis. R-IM also showed a stronger inhibitory effect than S-IM on the transcription of photosynthesis-related genes, affecting linear electron transport and CO(2) fixation. IM stress enantioselectively induced transcriptional upregulation of the ndhH gene, a representative of the NDH complex. In contrast, the expression of pgr5 was downregulated, which demonstrated that IM stress enhanced adenosine 5'-triphosphate (ATP) synthesis by stimulating an NDH-dependent and not ferredoxin (FD)-independent route. This study suggested that R-IM has a greater toxic effect on photosynthesis than S-IM, affecting plant growth through chlorophyll synthesis.
College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, PR China.
Haifeng
H
Qian
Xiao
X
Han
Qiannan
Q
Zhang
Zhengqi
Z
Sun
Liwei
L
Sun
Zhengwei
Z
Fu
D017360:Arabidopsis / Q000187:drug effects / Q000378:metabolism*; D002734:Chlorophyll / Q000096:biosynthesis*; D006540:Herbicides / Q000737:chemistry / Q000494:pharmacology*; D009539:Nicotinic Acids / Q000737:chemistry / Q000494:pharmacology*; D010788:Photosynthesis / Q000187:drug effects*; D010940:Plant Proteins / Q000378:metabolism; D013237:Stereoisomerism
D006540:Herbicides; D009539:Nicotinic Acids; D010940:Plant Proteins; D002734:Chlorophyll; C093630:imazethapyr