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Relationship: 2203
Title
Decrease, Coupling of OXPHOS leads to Decrease, ATP pool
Upstream event
Downstream event
AOPs Referencing Relationship
| AOP Name | Adjacency | Weight of Evidence | Quantitative Understanding | Point of Contact | Author Status | OECD Status |
|---|---|---|---|---|---|---|
| Uncoupling of oxidative phosphorylation leading to growth inhibition via decreased cell proliferation | adjacent | High | High | Allie Always (send email) | Open for citation & comment | WPHA/WNT Endorsed |
| Uncoupling of oxidative phosphorylation leading to growth inhibition via ATP depletion associated cell death | adjacent | Moderate | Not Specified | Evgeniia Kazymova (send email) | Open for citation & comment | Under Development |
| Uncoupling of oxidative phosphorylation leading to growth inhibition via decreased Na-K ATPase activity | adjacent | Brendan Ferreri-Hanberry (send email) | Under development: Not open for comment. Do not cite | Under Development |
Taxonomic Applicability
Sex Applicability
| Sex | Evidence |
|---|---|
| Unspecific | High |
Life Stage Applicability
| Term | Evidence |
|---|---|
| Embryo | High |
| Juvenile | High |
This key event relationship describes the dissipation of protonmotive force across the inner mitochondrial membrane by uncouplers (uncoupling of oxidative phosphorylation), leading to reduced total adenosine triphosphate (ATP) pool in cells or organisms.
| ID | Experimental Design | Species | Upstream Observation | Downstream Observation | Citation (first author, year) | Notes |
|---|
| Title | First Author | Biological Plausibility |
Dose Concordance |
Temporal Concordance |
Incidence Concordance |
|---|
Biological Plausibility
Dose Concordance Evidence
Temporal Concordance Evidence
Incidence Concordance Evidence
Uncertainties and Inconsistencies
- A significant decrease followed by a significant increase in total ATP was observed in human RD cells during a 48h exposure to the uncoupler FCCP (Kuruvilla 2003), possibly due to the enhancement of other ATP synthetic pathways (e.g., glycolysis) as a compensatory action to impaired OXPHOS (Jose 2011
The quantitative understanding of Relationship 2203 is high.
Rationale: Multiple mathematical models have been developed for describing the quantitative relationships between uncoupling of OXPHOS and ATP synthesis in vertebrates (Beard 2005; Schmitz 2011; Heiske 2017; Kubo 2020). These models, however, are highly complex metabolic or systems biological models and warrant further simplification to be used for this AOP.
Response-response Relationship
A regression based quantitative response-response relationship between uncoupling of OXPHOS and ATP depletion was proposed for the crustacean Daphnia magna under UVB stress (Song 2020).
Time-scale
Known Feedforward/Feedback loops influencing this KER
- It is known that mild uncoupling of oxidative phosphorylation can enhance the activity of the mitochondrial electron transport chain to produce more ATP, and/or activate other ATP synthetic pathways (e.g., glycolysis) as a compensatory action to impaired OXPHOS (Jose 2011).
Taxonomic applicability
Relationship 2203 is considered applicable to eukaryotes, as mitochondrial oxidative phosphorylation and ATP synthesis are highly conserved in these organisms. Uncoupling of oxidative phosphorylation leading to ATP depletion is a well-documented relationship in many taxa, such as human, rodents and fish.
Sex applicability
Relationship 2203 is considered applicable to all genders, as mitochondrial oxidative phosphorylation and ATP synthesis are fundamental biological processes and are not sex-pecific.
Life-stage applicability
Relationship 2203 is considered applicable to all life-stages, as mitochondrial oxidative phosphorylation and ATP synthesis are essential energy production processes for maintaining basic biological activities.