Component

Human mitochondrial tRNA modification protein / MTO1

Context-specific entity; species, compartment and exposure are stated on each claim.

4 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.

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.

Recorded relationships

What it acts on

  1. Reconstituting the human MTO1-GTPBP3 complex with hypomodified mitochondrial tRNA, taurine and 5,10-methylene-THF produced the taurine-containing U34 modification.

    Experimental context and source evidence
    evidence_access
    Primary full text, in-vitro reconstitution methods and results
    experimental_model
    Human enzyme-complex reconstitution and mass spectrometry.
    limitations
    The reaction mixture also contained GTP, ATP, FAD, NADH, NADPH and magnesium; their presence alone does not demonstrate each is individually limiting.
    nutrient_topic
    Taurine collection; molecular form, preparation, species, exposure and manipulation remain explicit. · Taurine
    plain_language
    Two proteins join taurine and a folate-derived carbon unit onto mitochondrial tRNA.
    primary_references
    Metabolic and chemical regulation of tRNA modification associated with taurine deficiency and human disease. · 2018 · https://pubmed.ncbi.nlm.nih.gov/29390138/ · DOI 10.1093/nar/gky068

    Taurine: synthesis, transport, mitochondrial decoding and nutrient interactions (2026-09-19) · lines 201–207

    AI-assisted research curation; primary-abstract references and experimental limitations individually identified. Not publisher full text. · supports · Human enzyme-complex reconstitution and mass spectrometry. · source_derived_draft · unverified_draft

    ## taurine-mto1-gtpbp3 Two proteins join taurine and a folate-derived carbon unit onto mitochondrial tRNA. Reconstituting the human MTO1-GTPBP3 complex with hypomodified mitochondrial tRNA, taurine and 5,10-methylene-THF produced the taurine-containing U34 modification. Model: Human enzyme-complex reconstitution and mass spectrometry. Limitations: The reaction mixture also contained GTP, ATP, FAD, NADH, NADPH and magnesium; their presence alone does not demonstrate each is individually limiting. Evidence access: Primary full text, in-vitro reconstitution methods and results Metabolic and chemical regulation of tRNA modification associated with taurine deficiency and human disease. · 2018 · https://pubmed.ncbi.nlm.nih.gov/29390138/ · DOI 10.1093/nar/gky068
    Complete structured claim and evidence

Where it participates (unsigned role)

  1. Isotope tracing supported the beta-carbon of serine entering the methylene group of mitochondrial taurine-modified uridine through 5,10-methylene-THF.

    Experimental context and source evidence
    evidence_access
    Primary full text, Figure 1 and metabolic-labeling experiments
    experimental_model
    Human HeLa metabolic labeling plus biochemical reconstitution.
    limitations
    A folate connection is not evidence for a benefit from folic acid supplementation in replete people.
    nutrient_topic
    Taurine collection; molecular form, preparation, species, exposure and manipulation remain explicit. · Taurine
    plain_language
    Folate chemistry contributes part of the RNA mark; taurine supplies a different part.
    primary_references
    Metabolic and chemical regulation of tRNA modification associated with taurine deficiency and human disease. · 2018 · https://pubmed.ncbi.nlm.nih.gov/29390138/ · DOI 10.1093/nar/gky068

    Taurine: synthesis, transport, mitochondrial decoding and nutrient interactions (2026-09-19) · lines 209–215

    AI-assisted research curation; primary-abstract references and experimental limitations individually identified. Not publisher full text. · supports · Human HeLa metabolic labeling plus biochemical reconstitution. · source_derived_draft · unverified_draft

    ## taurine-folate-carbon-donor Folate chemistry contributes part of the RNA mark; taurine supplies a different part. Isotope tracing supported the beta-carbon of serine entering the methylene group of mitochondrial taurine-modified uridine through 5,10-methylene-THF. Model: Human HeLa metabolic labeling plus biochemical reconstitution. Limitations: A folate connection is not evidence for a benefit from folic acid supplementation in replete people. Evidence access: Primary full text, Figure 1 and metabolic-labeling experiments Metabolic and chemical regulation of tRNA modification associated with taurine deficiency and human disease. · 2018 · https://pubmed.ncbi.nlm.nih.gov/29390138/ · DOI 10.1093/nar/gky068
    Complete structured claim and evidence
  2. Purified mature human GTPBP3 exhibited GTPase activity, and functional experiments linked that activity to tRNA modification.

    Experimental context and source evidence
    evidence_access
    Primary abstract
    experimental_model
    Human enzyme kinetics and cellular/yeast functional studies.
    limitations
    Results depend on the mature protein construct; do not infer benefit from dietary nucleotide supplements.
    nutrient_topic
    Taurine collection; molecular form, preparation, species, exposure and manipulation remain explicit. · Taurine
    plain_language
    The modifying complex includes a GTP-powered component.
    primary_references
    The human tRNA taurine modification enzyme GTPBP3 is an active GTPase linked to mitochondrial diseases. · 2021 · https://pubmed.ncbi.nlm.nih.gov/33619562/ · DOI 10.1093/nar/gkab104

    Taurine: synthesis, transport, mitochondrial decoding and nutrient interactions (2026-09-19) · lines 265–271

    AI-assisted research curation; primary-abstract references and experimental limitations individually identified. Not publisher full text. · supports · Human enzyme kinetics and cellular/yeast functional studies. · source_derived_draft · unverified_draft

    ## taurine-gtpbp3-gtpase The modifying complex includes a GTP-powered component. Purified mature human GTPBP3 exhibited GTPase activity, and functional experiments linked that activity to tRNA modification. Model: Human enzyme kinetics and cellular/yeast functional studies. Limitations: Results depend on the mature protein construct; do not infer benefit from dietary nucleotide supplements. Evidence access: Primary abstract The human tRNA taurine modification enzyme GTPBP3 is an active GTPase linked to mitochondrial diseases. · 2021 · https://pubmed.ncbi.nlm.nih.gov/33619562/ · DOI 10.1093/nar/gkab104
    Complete structured claim and evidence
  3. Taurine starvation reduced mitochondrial tRNA taurine modification in cultured cells, with corresponding dietary-depletion observations in cat liver and flatfish tissues.

    Experimental context and source evidence
    availability_state
    nutrient_deficiency Imported condition classification; unverified.
    evidence_access
    Primary abstract
    experimental_model
    Cultured-cell and dietary animal experiments.
    limitations
    Cats and flatfish differ from adult humans in endogenous taurine synthesis; no universal human plasma threshold was determined.
    nutrient_topic
    Taurine collection; molecular form, preparation, species, exposure and manipulation remain explicit. · Taurine
    plain_language
    Insufficient taurine can leave fewer tRNAs carrying the normal mark.
    primary_references
    Metabolic and chemical regulation of tRNA modification associated with taurine deficiency and human disease. · 2018 · https://pubmed.ncbi.nlm.nih.gov/29390138/ · DOI 10.1093/nar/gky068
    trigger_kind
    nutrient_deficiency Imported condition classification; unverified.

    Taurine: synthesis, transport, mitochondrial decoding and nutrient interactions (2026-09-19) · lines 233–239

    AI-assisted research curation; primary-abstract references and experimental limitations individually identified. Not publisher full text. · supports · Cultured-cell and dietary animal experiments. · source_derived_draft · unverified_draft

    ## taurine-taurine-starvation-rna Insufficient taurine can leave fewer tRNAs carrying the normal mark. Taurine starvation reduced mitochondrial tRNA taurine modification in cultured cells, with corresponding dietary-depletion observations in cat liver and flatfish tissues. Model: Cultured-cell and dietary animal experiments. Limitations: Cats and flatfish differ from adult humans in endogenous taurine synthesis; no universal human plasma threshold was determined. Evidence access: Primary abstract Metabolic and chemical regulation of tRNA modification associated with taurine deficiency and human disease. · 2018 · https://pubmed.ncbi.nlm.nih.gov/29390138/ · DOI 10.1093/nar/gky068
    Complete structured claim and evidence

In the sources

Preserved passages that mention this component, quoted exactly. Open one to read it in context.

    This is a research prototype built from draft material. It is not medical advice, and its statements still await verification against the original studies.

    Evidence, AI assistance and curation standards