Abstract
Catalase (CAT) dismutates the reactive oxygen species H2O2 into water and dioxygen and in plants; it is located in peroxisomes and glyoxysomes. In the present study, we investigated the effect of cadmium (a well-known oxidative stress inducer) on catalase in roots and cotyledons of developing sunflower seedlings, at 10 microM and 100 microM. Although germination was unaltered after 48 h of exposure to 100 microM Cd2+, root length was significantly reduced. CAT activity was also significantly reduced, but this activity was completely restored (10 microM treatment) or even enhanced (100 microM treatment) 24 h later. Although CAT protein abundance remained similar to control in roots and cotyledons of Cd-treated seedlings, cadmium produced CAT protein oxidation, indicating that the mechanism of CAT inactivation by Cd2+ involves oxidation of the protein structure. The transcripts of the four genes described for sunflower (CATA1 to CATA4) increased after cadmium treatment; CATA1 and CATA2 were the most overexpressed in cotyledon and root, respectively. The differential expression of catalase genes in sunflower seedlings under Cd stress might be related to the synthesis of CAT isoforms less sensitive to oxidation, which would prevent enzyme inactivation and H2O2 accumulation.
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Claims 11
Claim · model-written summary
Germination of sunflower seedlings was unaltered after 48 h of exposure to 100 microM Cd2+.
- Taxon
- sunflower
Helianthus annuust0 - Treatment
- 100 microM Cd2+e1
- Outcome
- germinatione1
- Direction
- unalterede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“developing sunflower seedlings under cadmium stress”
e1“Although germination was unaltered after 48 h of exposure to 100 microM Cd2+, root length was significantly reduced”
Claim · model-written summary
Root length of sunflower seedlings was significantly reduced by 100 microM Cd2+ after 48 h.
- Taxon
- sunflowerHelianthus annuust0
- Treatment
- 100 microM Cd2+e1
- Outcome
- root lengthe1
- Direction
- significantly reducede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“developing sunflower seedlings under cadmium stress”
e1“Although germination was unaltered after 48 h of exposure to 100 microM Cd2+, root length was significantly reduced”
Claim · model-written summary
Cadmium stress significantly reduced CAT activity in sunflower seedlings.
- Taxon
- sunflowerHelianthus annuust0
- Treatment
- cadmium stresst0
- Outcome
- CAT activitye2
- Direction
- significantly reducede2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“developing sunflower seedlings under cadmium stress”
e2“CAT activity was also significantly reduced”
Claim · model-written summary
At 10 microM treatment, CAT activity was completely restored 24 h later.
- Taxon
- sunflowerHelianthus annuust0
- Treatment
- 10 microM treatmente3
- Outcome
- CAT activitye2
- Direction
- completely restorede3
- Qualifier
- 24 h latere3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“developing sunflower seedlings under cadmium stress”
e2“CAT activity was also significantly reduced”
e3“this activity was completely restored (10 microM treatment) or even enhanced (100 microM treatment) 24 h later”
Claim · model-written summary
At 100 microM treatment, CAT activity was even enhanced 24 h later.
- Taxon
- sunflowerHelianthus annuust0
- Treatment
- 100 microM treatmente3
- Outcome
- CAT activitye2
- Direction
- even enhancede3
- Qualifier
- 24 h latere3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“developing sunflower seedlings under cadmium stress”
e2“CAT activity was also significantly reduced”
e3“this activity was completely restored (10 microM treatment) or even enhanced (100 microM treatment) 24 h later”
Claim · model-written summary
CAT protein abundance remained similar to control in roots and cotyledons of Cd-treated sunflower seedlings.
- Taxon
- sunflowerHelianthus annuust0
- Organ / stage
- roots and cotyledonse4
- Treatment
- Cd-treatede4
- Outcome
- CAT protein abundancee4
- Direction
- remained similare4
- Comparator
- controle4
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“developing sunflower seedlings under cadmium stress”
e4“Although CAT protein abundance remained similar to control in roots and cotyledons of Cd-treated seedlings”
Claim · model-written summary
Cadmium produced oxidation of CAT protein in sunflower seedlings.
- Taxon
- sunflowerHelianthus annuust0
- Treatment
- cadmiume5
- Outcome
- CAT protein oxidatione5
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“developing sunflower seedlings under cadmium stress”
e5“cadmium produced CAT protein oxidation”
Claim · model-written summary
CAT inactivation by Cd2+ is attributed to oxidation of the protein structure.
- Taxon
- sunflowerHelianthus annuust0
- Outcome
- CAT inactivatione6
- Qualifier
- oxidation of the protein structuree6
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“developing sunflower seedlings under cadmium stress”
e6“indicating that the mechanism of CAT inactivation by Cd2+ involves oxidation of the protein structure”
Claim · model-written summary
Transcripts of the four CATA genes increased after cadmium treatment in sunflower.
- Taxon
- sunflowerHelianthus annuuse7
- Treatment
- cadmium treatmente7
- Gene
- CATA1 to CATA4e7
- Outcome
- transcriptse7
- Direction
- increasede7
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e7“The transcripts of the four genes described for sunflower (CATA1 to CATA4) increased after cadmium treatment”
Claim · model-written summary
CATA1 was the most overexpressed catalase gene in cotyledon of cadmium-stressed sunflower seedlings.
- Taxon
- sunflowerHelianthus annuust0
- Organ / stage
- cotyledone7
- Treatment
- cadmium stresst0
- Gene
- CATA1e7
- Outcome
- overexpressede7
- Direction
- most overexpressede7
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“developing sunflower seedlings under cadmium stress”
e7“CATA1 and CATA2 were the most overexpressed in cotyledon and root, respectively”
Claim · model-written summary
CATA2 was the most overexpressed catalase gene in root of cadmium-stressed sunflower seedlings.
- Taxon
- sunflowerHelianthus annuust0
- Organ / stage
- roote7
- Treatment
- cadmium stresst0
- Gene
- CATA2e7
- Outcome
- overexpressede7
- Direction
- most overexpressede7
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“developing sunflower seedlings under cadmium stress”
e7“CATA1 and CATA2 were the most overexpressed in cotyledon and root, respectively”
The same questions in other papers
cadmium atom · physiology: antioxidant enzymes · Helianthus annuus (common sunflower)Results differ
3 papers in the same direction as this paper · 4 in the opposite direction
- positive
- positive
- positive
4 papers more in this group
See all 8 papers →cadmium(2+) · growth · Helianthus annuus (common sunflower)Results agree
1 paper in the same direction as this paper
- negative
heavy metal · physiology: antioxidant enzymes · Helianthus annuus (common sunflower)Positive and negative results
2 papers in the same direction as this paper · 1 in the opposite direction
- positive
- negative
- no effect
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.