Abstract
We examined the effects of Cd and Zn exposure on the photosynthetic function and the tolerant mechanisms of ROS metabolism in tobacco leaves. The results showed that the photosynthesis inhibition caused by Cd exposure was due to the limitation of both stomatal and non-stomatal factors, while Zn exposure only showed a significant effect on the Gs of tobacco leaves. Cd increased the generation rate of O2•– and the content of H2O2, but Zn did not lead to the ROS burst. Cd enhanced the POD activity, but inhibited SOD and CAT activities. The activities of SOD and POD significantly increased under Zn exposure. Cd inhibited the activity and expression of APX. The up regulation of GPX, GR and GST expression and the increase of their activities also play a positive role in the adaptation to Cd. Although Zn inhibited the activities of APX and GPX, it had little effect on other enzyme activities and protein expression in AsA-GSH cycle. TPX and TrxR activities, Trx-Prx pathway-related proteins are very sensitive to Cd. However, only PrxQ and 2-Cys Prx BAS1, which are located in chloroplast, and Trx-HFC164 were significantly down-regulated in Trx-Prx pathway under Zn exposure.
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Claims 13
Claim · model-written summary
Photosynthesis inhibition caused by Cd exposure in tobacco leaves was due to limitation of both stomatal and non-stomatal factors.
- Taxon
- tobacco
Nicotiana tabacumt0 - Treatment
- Cd exposuree0
- Outcome
- photosynthesise0
- Direction
- inhibitione0
- Qualifier
- limitation of both stomatal and non-stomatal factorse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the photosynthesis inhibition caused by Cd exposure was due to the limitation of both stomatal and non-stomatal factors”
t0“tobacco leaves”
Claim · model-written summary
Zn exposure only had a significant effect on Gs in tobacco leaves.
- Taxon
- tobaccoNicotiana tabacume0
- Treatment
- Zn exposuree0
- Outcome
- Gse0
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Zn exposure only showed a significant effect on the Gs of tobacco leaves”
Claim · model-written summary
Cd increased the generation rate of O2 radical and the H2O2 content in tobacco leaves.
- Taxon
- tobaccoNicotiana tabacumt0
- Treatment
- Cde0
- Outcome
- generation rate of O2•– and the content of H2O2e0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Cd increased the generation rate of O2•– and the content of H2O2”
t0“tobacco leaves”
Claim · model-written summary
Zn did not lead to a ROS burst in tobacco leaves.
- Taxon
- tobaccoNicotiana tabacumt0
- Treatment
- Zne0
- Outcome
- ROS burste0
- Direction
- no_changeinferrede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Zn did not lead to the ROS burst”
t0“tobacco leaves”
Claim · model-written summary
Cd enhanced POD activity in tobacco leaves.
- Taxon
- tobaccoNicotiana tabacumt0
- Treatment
- Cde0
- Outcome
- POD activitye0
- Direction
- enhancede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Cd enhanced the POD activity, but inhibited SOD and CAT activities”
t0“tobacco leaves”
Claim · model-written summary
Cd inhibited SOD and CAT activities in tobacco leaves.
- Taxon
- tobaccoNicotiana tabacumt0
- Treatment
- Cde0
- Outcome
- SOD and CAT activitiese0
- Direction
- inhibitede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Cd enhanced the POD activity, but inhibited SOD and CAT activities”
t0“tobacco leaves”
Claim · model-written summary
SOD and POD activities increased significantly under Zn exposure in tobacco leaves.
- Taxon
- tobaccoNicotiana tabacumt0
- Treatment
- Zn exposuree0
- Outcome
- activities of SOD and PODe0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The activities of SOD and POD significantly increased under Zn exposure”
t0“tobacco leaves”
Claim · model-written summary
Cd inhibited both the activity and the expression of APX in tobacco leaves.
- Taxon
- tobaccoNicotiana tabacumt0
- Treatment
- Cde0
- Outcome
- activity and expression of APXe0
- Direction
- inhibitede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Cd inhibited the activity and expression of APX”
t0“tobacco leaves”
Claim · model-written summary
Up-regulated expression and increased activities of GPX, GR and GST are presented as playing a positive role in adaptation to Cd in tobacco leaves.
- Taxon
- tobaccoNicotiana tabacumt0
- Gene
- GPX, GR and GSTe0
- Outcome
- adaptation to Cde0
- Qualifier
- up regulation of GPX, GR and GST expression and the increase of their activitiese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The up regulation of GPX, GR and GST expression and the increase of their activities also play a positive role in the adaptation to Cd”
t0“tobacco leaves”
Claim · model-written summary
Zn inhibited the activities of APX and GPX in tobacco leaves.
- Taxon
- tobaccoNicotiana tabacumt0
- Treatment
- Zne0
- Outcome
- activities of APX and GPXe0
- Direction
- inhibitede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Zn inhibited the activities of APX and GPX”
t0“tobacco leaves”
Claim · model-written summary
Zn had little effect on other enzyme activities and protein expression in the AsA-GSH cycle in tobacco leaves.
- Taxon
- tobaccoNicotiana tabacumt0
- Outcome
- other enzyme activities and protein expression in AsA-GSH cyclee0
- Direction
- no_changeinferrede0
Not reportedTreatmentComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“it had little effect on other enzyme activities and protein expression in AsA-GSH cycle”
t0“tobacco leaves”
Claim · model-written summary
TPX and TrxR activities and Trx-Prx pathway-related proteins are very sensitive to Cd in tobacco leaves.
- Taxon
- tobaccoNicotiana tabacumt0
- Treatment
- Cde0
- Outcome
- TPX and TrxR activities, Trx-Prx pathway-related proteinse0
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“TPX and TrxR activities, Trx-Prx pathway-related proteins are very sensitive to Cd”
t0“tobacco leaves”
Claim · model-written summary
Under Zn exposure only PrxQ and 2-Cys Prx BAS1 and Trx-HFC164 were significantly down-regulated in the Trx-Prx pathway in tobacco leaves.
- Taxon
- tobaccoNicotiana tabacumt0
- Treatment
- Zn exposuree0
- Gene
- PrxQ and 2-Cys Prx BAS1e0
- Outcome
- down-regulated in Trx-Prx pathwaye0
- Direction
- down-regulatede0
- Qualifier
- Trx-HFC164e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“only PrxQ and 2-Cys Prx BAS1, which are located in chloroplast, and Trx-HFC164 were significantly down-regulated in Trx-Prx pathway under Zn exposure”
t0“tobacco leaves”
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See all 7 papers →8 of 9 groups shown: named compounds and organisms first, then groups whose results differ (checked claim by claim), then those with positive and negative results, then the smaller groups.
Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.