Our results show that the best promoters for our objective are Citrate synthase 4 (CSY4), Glyceraldehyde-3-phosphate dehydrogenase (G3PDH) and Adenosine Triosephosphate Synthase (ATPS). But let us explain the data in more detail.
G3PDH
Visual exam
| Ambient CO2 | Higher CO2 |
|---|---|
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Quantitative exam
| Ambient CO2 | Higher CO2 |
|---|---|
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Both on the visual examination and in the quantification graph we can see that the intensity is much higher in the plants exposed to higher CO2 than in the ones on ambient CO2. The first reaches an intensity of 80 units while the exposed to higher CO2 has a peak of 150 units of intensity.
CSY4
Visual exam
| Ambient CO2 | Higher CO2 |
|---|---|
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Quantitative exam
| Ambient CO2 | Higher CO2 |
|---|---|
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Both on the visual examination and in the quantification graph we can see that the intensity is much higher in the plants exposed to higher CO2 than in the ones on ambient CO2. The first reaches an intensity of 25 units while the exposed to higher CO2 has a peak of 250 units of intensity.
ATPS
Visual exam
| Ambient CO2 | Higher CO2 |
|---|---|
 |
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Quantitative exam
| Ambient CO2 | Higher CO2 |
|---|---|
 |
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Both on the visual examination and in the quantification graph we can see that the intensity is much higher in the plants exposed to higher CO2 than in the ones on ambient CO2. The first reaches an intensity of 150 units while the exposed to higher CO2 has a peak of 250 units of intensity.
Hypothesis
We have found a relationship between the function of the promoters and the results of our three most successful samples.
- Stimulated leaf nocturnal respiration is a response that happens when plants are exposed to high CO2 concentration. GA3PDH and CSY4 are enzymes involved in this process. This is a way to obtain energy from the metabolites formed by a higher rate of photosynthesis.
- Respiratory chain activation is needed to maintain both the carbon and energy balance in leaves during growth at high CO2. In this process ATPase plays an important role.
So we hope the next Navarra Biogalaxy team would continue our work by doing further studies with these three promoters.
Discarded promoters
We have classified a sample as discarded when the difference between exposed and non-exposed was similar. This is because the absence of changes indicates that the promoter is not activated when exposed to high CO2 concentrations and, therefore, cannot be used to generate plant biomarkers.
In the next table we show the results of the promoters that had similar expression in ambient and high CO2 concentration.
| Promoter | Ambient CO2 | Higher CO2 |
|---|---|---|
| ADH1 |  |
 |
| CI76 |  |
 |
| PEPCI |  |
 |
| ALDH2 |  |
 |
| CIII14 |  |
 |
| HB1 |  |
 |
| HB2 |  |
 |
| ACO3 |  |
 |