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response to high light intensity

Definition

Target type: biologicalprocess

Any process that results in a change in state or activity of a cell or an organism (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of a high light intensity stimulus. [GOC:go_curators]

Response to high light intensity is a complex process involving multiple cellular mechanisms to protect against photodamage and maintain photosynthetic efficiency. Upon exposure to high light, plants initiate a cascade of events, including:

1. **Non-photochemical quenching (NPQ):** This process dissipates excess light energy as heat, preventing harmful reactive oxygen species (ROS) formation. NPQ is mediated by the xanthophyll cycle, where violaxanthin is converted to zeaxanthin, which enhances energy dissipation.

2. **Photoprotective pigments:** Carotenoids, particularly beta-carotene, act as antioxidants, scavenging ROS and protecting chlorophyll from photooxidation.

3. **Repair mechanisms:** Damaged proteins and chlorophylls are repaired or replaced through complex enzymatic pathways.

4. **Leaf movement:** Some plants exhibit phototropism, adjusting leaf angles to minimize direct sunlight exposure during high light periods.

5. **Leaf senescence:** In extreme cases, prolonged exposure to high light can induce leaf senescence, leading to shedding of old, damaged leaves.

6. **Transcriptional regulation:** High light triggers changes in gene expression, upregulating genes involved in photoprotection and downregulating genes related to photosynthesis.

7. **Signal transduction pathways:** Various signaling molecules, including reactive oxygen species (ROS), calcium ions, and hormones like abscisic acid (ABA), play critical roles in relaying high light signals within the plant.

8. **Hormonal response:** High light can trigger hormonal responses, such as increased production of abscisic acid (ABA), which can influence stomatal closure and reduce water loss.

These interconnected mechanisms ensure that plants can effectively cope with high light stress, maintaining their photosynthetic capacity and survival in challenging environments.'
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Proteins (2)

ProteinDefinitionTaxonomy
Sodium channel protein type 11 subunit alphaA sodium channel protein type 11 subunit alpha that is encoded in the genome of human. [PRO:WCB, UniProtKB:Q9UI33]Homo sapiens (human)
Sodium/potassium/calcium exchanger 4A sodium/potassium/calcium exchanger 4 that is encoded in the genome of human. [PRO:DNx, UniProtKB:Q8NFF2]Homo sapiens (human)

Compounds (19)

CompoundDefinitionClassesRoles
amiodaroneamiodarone : A member of the class of 1-benzofurans that is 1-benzofuran substituted by a butyl group at position 2 and a 4-[2-(diethylamino)ethoxy]-3,5-diiodobenzoyl group at position 3. It is a cardiovascular drug used for the treatment of cardiac dysrhythmias.

Amiodarone: An antianginal and class III antiarrhythmic drug. It increases the duration of ventricular and atrial muscle action by inhibiting POTASSIUM CHANNELS and VOLTAGE-GATED SODIUM CHANNELS. There is a resulting decrease in heart rate and in vascular resistance.
1-benzofurans;
aromatic ketone;
organoiodine compound;
tertiary amino compound
cardiovascular drug
amitriptylineamitriptyline : An organic tricyclic compound that is 10,11-dihydro-5H-dibenzo[a,d][7]annulene substituted by a 3-(dimethylamino)propylidene group at position 5.

Amitriptyline: Tricyclic antidepressant with anticholinergic and sedative properties. It appears to prevent the re-uptake of norepinephrine and serotonin at nerve terminals, thus potentiating the action of these neurotransmitters. Amitriptyline also appears to antagonize cholinergic and alpha-1 adrenergic responses to bioactive amines.
carbotricyclic compound;
tertiary amine
adrenergic uptake inhibitor;
antidepressant;
environmental contaminant;
tropomyosin-related kinase B receptor agonist;
xenobiotic
chlorpromazinechlorpromazine : A substituted phenothiazine in which the ring nitrogen at position 10 is attached to C-3 of an N,N-dimethylpropanamine moiety.

Chlorpromazine: The prototypical phenothiazine antipsychotic drug. Like the other drugs in this class chlorpromazine's antipsychotic actions are thought to be due to long-term adaptation by the brain to blocking DOPAMINE RECEPTORS. Chlorpromazine has several other actions and therapeutic uses, including as an antiemetic and in the treatment of intractable hiccup.
organochlorine compound;
phenothiazines;
tertiary amine
anticoronaviral agent;
antiemetic;
dopaminergic antagonist;
EC 3.4.21.26 (prolyl oligopeptidase) inhibitor;
phenothiazine antipsychotic drug
cifenlinediarylmethane
haloperidolhaloperidol : A compound composed of a central piperidine structure with hydroxy and p-chlorophenyl substituents at position 4 and an N-linked p-fluorobutyrophenone moiety.

Haloperidol: A phenyl-piperidinyl-butyrophenone that is used primarily to treat SCHIZOPHRENIA and other PSYCHOSES. It is also used in schizoaffective disorder, DELUSIONAL DISORDERS, ballism, and TOURETTE SYNDROME (a drug of choice) and occasionally as adjunctive therapy in INTELLECTUAL DISABILITY and the chorea of HUNTINGTON DISEASE. It is a potent antiemetic and is used in the treatment of intractable HICCUPS. (From AMA Drug Evaluations Annual, 1994, p279)
aromatic ketone;
hydroxypiperidine;
monochlorobenzenes;
organofluorine compound;
tertiary alcohol
antidyskinesia agent;
antiemetic;
dopaminergic antagonist;
first generation antipsychotic;
serotonergic antagonist
imipramineimipramine : A dibenzoazepine that is 5H-dibenzo[b,f]azepine substituted by a 3-(dimethylamino)propyl group at the nitrogen atom.

Imipramine: The prototypical tricyclic antidepressant. It has been used in major depression, dysthymia, bipolar depression, attention-deficit disorders, agoraphobia, and panic disorders. It has less sedative effect than some other members of this therapeutic group.
dibenzoazepineadrenergic uptake inhibitor;
antidepressant;
EC 3.4.21.26 (prolyl oligopeptidase) inhibitor
mexiletinemexiletine : An aromatic ether which is 2,6-dimethylphenyl ether of 2-aminopropan-1-ol.

Mexiletine: Antiarrhythmic agent pharmacologically similar to LIDOCAINE. It may have some anticonvulsant properties.
aromatic ether;
primary amino compound
anti-arrhythmia drug
nifedipineNifedipine: A potent vasodilator agent with calcium antagonistic action. It is a useful anti-anginal agent that also lowers blood pressure.C-nitro compound;
dihydropyridine;
methyl ester
calcium channel blocker;
human metabolite;
tocolytic agent;
vasodilator agent
nitrendipinenitrendipine : A dihydropyridine that is 1,4-dihydropyridine substituted by methyl groups at positions 2 and 6, a 3-nitrophenyl group at position 4, a ethoxycarbonyl group at position 3 and a methoxycarbonyl group at position 5. It is a calcium-channel blocker used in the treatment of hypertension.

Nitrendipine: A calcium channel blocker with marked vasodilator action. It is an effective antihypertensive agent and differs from other calcium channel blockers in that it does not reduce glomerular filtration rate and is mildly natriuretic, rather than sodium retentive.
C-nitro compound;
dicarboxylic acids and O-substituted derivatives;
diester;
dihydropyridine;
ethyl ester;
methyl ester
antihypertensive agent;
calcium channel blocker;
geroprotector;
vasodilator agent
potassium chloridepotassium chloride : A metal chloride salt with a K(+) counterion.

Potassium Chloride: A white crystal or crystalline powder used in BUFFERS; FERTILIZERS; and EXPLOSIVES. It can be used to replenish ELECTROLYTES and restore WATER-ELECTROLYTE BALANCE in treating HYPOKALEMIA.
inorganic chloride;
inorganic potassium salt;
potassium salt
fertilizer
pimozidepimozide : A member of the class of benzimidazoles that is 1,3-dihydro-2H-benzimidazol-2-one in which one of the nitrogens is substituted by a piperidin-4-yl group, which in turn is substituted on the nitrogen by a 4,4-bis(p-fluorophenyl)butyl group.

Pimozide: A diphenylbutylpiperidine that is effective as an antipsychotic agent and as an alternative to HALOPERIDOL for the suppression of vocal and motor tics in patients with Tourette syndrome. Although the precise mechanism of action is unknown, blockade of postsynaptic dopamine receptors has been postulated. (From AMA Drug Evaluations Annual, 1994, p403)
benzimidazoles;
heteroarylpiperidine;
organofluorine compound
antidyskinesia agent;
dopaminergic antagonist;
first generation antipsychotic;
H1-receptor antagonist;
serotonergic antagonist
diltiazemdiltiazem : A 5-[2-(dimethylamino)ethyl]-2-(4-methoxyphenyl)-4-oxo-2,3,4,5-tetrahydro-1,5-benzothiazepin-3-yl acetate in which both stereocentres have S configuration. A calcium-channel blocker and vasodilator, it is used as the hydrochloride in the management of angina pectoris and hypertension.

Diltiazem: A benzothiazepine derivative with vasodilating action due to its antagonism of the actions of CALCIUM ion on membrane functions.
5-[2-(dimethylamino)ethyl]-2-(4-methoxyphenyl)-4-oxo-2,3,4,5-tetrahydro-1,5-benzothiazepin-3-yl acetateantihypertensive agent;
calcium channel blocker;
vasodilator agent
sertindolesertindole : A phenylindole that is 1H-indole which is substituted on the nitrogen by a p-chlorophenyl group, at position 5 by chlorine, and at position 3 by a piperidin-4-yl group, which is itself substituted on the nitrogen by a 2-(2-oxoimidazolidin-1-yl)ethyl group.heteroarylpiperidine;
imidazolidinone;
organochlorine compound;
organofluorine compound;
phenylindole
alpha-adrenergic antagonist;
H1-receptor antagonist;
second generation antipsychotic;
serotonergic antagonist
mibefradilMibefradil: A benzimidazoyl-substituted tetraline that selectively binds and inhibits CALCIUM CHANNELS, T-TYPE.tetralinsT-type calcium channel blocker
tedisamiltedisamil : A member of the class of diazabicyclononanes that is (1s,5s)-3,7-diazaspiro[bicyclo[3.3.1]nonane-9,1'-cyclopentane] in which the hydrogens at positions 3 and 7 are replaced by cyclopropylmethyl groups. It is a potassium channel blocker and an antiarrhythmic agent currently currently in development for the treatment of atrial fibrillation.
uk 68798aromatic ether;
sulfonamide;
tertiary amino compound
anti-arrhythmia drug;
potassium channel blocker
tetrodotoxin
saxitoxinsaxitoxin : An alkaloid isolated from the marine dinoflagellates and cyanobacteria that causes paralytic shellfish poisoning.

Saxitoxin: A compound that contains a reduced purine ring system but is not biosynthetically related to the purine alkaloids. It is a poison found in certain edible mollusks at certain times; elaborated by GONYAULAX and consumed by mollusks, fishes, etc. without ill effects. It is neurotoxic and causes RESPIRATORY PARALYSIS and other effects in MAMMALS, known as paralytic SHELLFISH poisoning.
alkaloid;
carbamate ester;
guanidines;
ketone hydrate;
paralytic shellfish toxin;
pyrrolopurine
cyanotoxin;
marine metabolite;
neurotoxin;
sodium channel blocker;
toxin
ajmaline