Component
The human OCT1 transmembrane helix 2 and 3 pair in the 2020 chimera study
The human OCT1 transmembrane helix 2 and 3 pair in the 2020 chimera study. Species, exposure and limitations are retained in each linked claim.
1 recorded relationships. Experimental role, claim status and evidence remain attached to each record.
How nutrients influence it
Every nutrient with a recorded effect on this component, credited to the nutrient that acted rather than the chapter that recorded it. Open a nutrient to see the findings and the conditions they were measured under.
Other things that act on it
Enzymes, hormones, genes, and other components with a recorded effect. These are not nutrients, so they do not count toward the arrows above. Each finding names the chapter that recorded it.
How nutrients reach it in more than one step
Chains of two or more recorded steps that end here, grouped by the nutrient they start from. Each step is a separate finding, so a chain is a route a mechanism could take, not proof that it does.
Tracing routes…
What it does
Every recorded relationship this component is part of, grouped by its role. Plain wording comes first; the technical statement follows.
What it acts on
Simultaneous substitution of transmembrane helices TMH2 and TMH3 reversed the affinity for metformin in human-mouse chimeric OCT1.
Experimental context and source evidence
- evidence_span
- {"source_cache": "artifacts/metformin-research/33037045.abstract.txt", "locator": "Indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "861e39b20a78d5d85a01c5de0febda8bf1c400de4fa8ef1e6944707521604c67", "start_char": 0, "end_char": 2296, "text_sha256": "861e39b20a78d5d85a01c5de0febda8bf1c400de4fa8ef1e6944707521604c67"}
- experimental_model
- Stably transfected HEK293 cells comparing human and mouse OCT1, with human-mouse chimeras and homology modelling
- exposure
- Metformin and thiamine uptake kinetics; transmembrane-helix substitutions
- limitations
- A species comparison of transport affinity. It limits how far mouse OCT1 results can be read as human ones; it is not itself a human tissue measurement.
- nutrient_topic
- Metformin research collection; topical membership is not evidence of a direct clinical effect, and pharmacological exposure is not dietary intake. · Metformin
- organism
- Human and mouse orthologues side by side
- plain_language
- Two helices carry the species difference in how tightly the drug binds.
- primary_references
- [metformin-p33037045] Differences in Metformin and Thiamine Uptake between Human and Mouse Organic Cation Transporter 1: Structural Determinants and Potential Consequences for Intrahepatic Concentrations. (2020). https://pubmed.ncbi.nlm.nih.gov/33037045/ DOI: 10.1124/dmd.120.000170
- tissue_or_cell_type
- Hepatic uptake
Metformin: transport, molecular targets, gut mechanisms and nutrient interactions (2026-09-19) · lines 346–357
AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Stably transfected HEK293 cells comparing human and mouse OCT1, with human-mouse chimeras and homology modelling · source_derived_draft · unverified_draft
### metformin-oct1-tmh-determinant Simultaneous substitution of transmembrane helices TMH2 and TMH3 reversed the affinity for metformin in human-mouse chimeric OCT1. Condition category: normal nutrient_topic: Metformin research collection; topical membership is not evidence of a direct clinical effect, and pharmacological exposure is not dietary intake. plain_language: Two helices carry the species difference in how tightly the drug binds. organism: Human and mouse orthologues side by side tissue_or_cell_type: Hepatic uptake experimental_model: Stably transfected HEK293 cells comparing human and mouse OCT1, with human-mouse chimeras and homology modelling limitations: A species comparison of transport affinity. It limits how far mouse OCT1 results can be read as human ones; it is not itself a human tissue measurement. exposure: Metformin and thiamine uptake kinetics; transmembrane-helix substitutions evidence_span: {"source_cache": "artifacts/metformin-research/33037045.abstract.txt", "locator": "Indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "861e39b20a78d5d85a01c5de0febda8bf1c400de4fa8ef1e6944707521604c67", "start_char": 0, "end_char": 2296, "text_sha256": "861e39b20a78d5d85a01c5de0febda8bf1c400de4fa8ef1e6944707521604c67"} [metformin-p33037045] Differences in Metformin and Thiamine Uptake between Human and Mouse Organic Cation Transporter 1: Structural Determinants and Potential Consequences for Intrahepatic Concentrations. (2020). https://pubmed.ncbi.nlm.nih.gov/33037045/ DOI: 10.1124/dmd.120.000170
Complete structured claim and evidence
The events it takes part in
A mechanism often involves more than two components. These are the full events, with every participant and its role.
Situations it appears in
Low-supply and faulty-machinery situations recorded in the chapters where this component plays a part.
In the sources
Preserved passages that mention this component, quoted exactly. Open one to read it in context.
Open hypotheses
Proposed ideas that involve this component. They are labeled as hypotheses and do not change any recorded statement.
This is a research prototype built from draft material. It is not medical advice, and its statements still await verification against the original studies.