Component

Dopaquinone

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

3 recorded relationships. Experimental role, claim status and evidence remain attached to each record.

Read recorded mechanisms Open recursive mind map

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 acts on it

  1. Recombinant human tyrosinase also showed diphenol oxidase activity with L-DOPA, supporting the next oxidation toward dopaquinone.

    Human tyrosinase / TYR → Dopaquinone source_derived_draftungraded
    Experimental context and source evidence
    evidence_access
    Primary full text; Results and catalytic assays
    experimental_model
    Purified human enzyme; L-DOPA colorimetric assays.
    limitations
    A colorimetric enzyme rate does not establish whole-body melanin output.
    nutrient_topic
    L-Tyrosine collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · L-Tyrosine
    plain_language
    The pigment route includes a separate oxidation step.
    primary_references
    Albinism-causing mutations in recombinant human tyrosinase alter intrinsic enzymatic activity. · 2014 · https://pubmed.ncbi.nlm.nih.gov/24392141/ · DOI 10.1371/journal.pone.0084494

    L-Tyrosine: catecholamines, thyroid chemistry, pigment, metabolism and cross-nutrient mechanisms (2026-09-19) · lines 156–162

    AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Purified human enzyme; L-DOPA colorimetric assays. · source_derived_draft · unverified_draft

    ## l-tyrosine-tyr-quinone The pigment route includes a separate oxidation step. Recombinant human tyrosinase also showed diphenol oxidase activity with L-DOPA, supporting the next oxidation toward dopaquinone. Model: Purified human enzyme; L-DOPA colorimetric assays. Limitations: A colorimetric enzyme rate does not establish whole-body melanin output. Evidence access: Primary full text; Results and catalytic assays Albinism-causing mutations in recombinant human tyrosinase alter intrinsic enzymatic activity. · 2014 · https://pubmed.ncbi.nlm.nih.gov/24392141/ · DOI 10.1371/journal.pone.0084494
    Complete structured claim and evidence

Where it participates (unsigned role)

  1. MFSD12 loss in human SKMEL30 cells reduced melanosomal cystine and cellular cysteinyldopas.

    Human MFSD12 cysteine transport component → Cysteinyldopa isomers, pheomelanin precursors source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    machinery_impairment Imported condition classification; unverified.
    evidence_access
    Primary full text; Fig. 2d–f
    experimental_model
    Human SKMEL30 loss-of-function; analogous mouse experiments were separately reported.
    limitations
    Lysosomal storage and melanosomal pigment endpoints differ.
    nutrient_topic
    L-Tyrosine collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · L-Tyrosine
    plain_language
    A missing transporter can redirect pigment chemistry even when precursors exist elsewhere.
    primary_references
    MFSD12 mediates the import of cysteine into melanosomes and lysosomes. · 2020 · https://pubmed.ncbi.nlm.nih.gov/33208952/ · DOI 10.1038/s41586-020-2937-x
    trigger_kind
    machinery_impairment Imported condition classification; unverified.

    L-Tyrosine: catecholamines, thyroid chemistry, pigment, metabolism and cross-nutrient mechanisms (2026-09-19) · lines 180–186

    AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Human SKMEL30 loss-of-function; analogous mouse experiments were separately reported. · source_derived_draft · unverified_draft

    ## l-tyrosine-mfsd12-loss A missing transporter can redirect pigment chemistry even when precursors exist elsewhere. MFSD12 loss in human SKMEL30 cells reduced melanosomal cystine and cellular cysteinyldopas. Model: Human SKMEL30 loss-of-function; analogous mouse experiments were separately reported. Limitations: Lysosomal storage and melanosomal pigment endpoints differ. Evidence access: Primary full text; Fig. 2d–f MFSD12 mediates the import of cysteine into melanosomes and lysosomes. · 2020 · https://pubmed.ncbi.nlm.nih.gov/33208952/ · DOI 10.1038/s41586-020-2937-x
    Complete structured claim and evidence

  2. Human TYR R422Q and R422W variants had lower activity and temperature sensitivity compared with wild type.

    Human tyrosinase / TYR → Human TYR R422Q/R422W pigment-enzyme activity source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    machinery_impairment Imported condition classification; unverified.
    evidence_access
    Primary abstract
    experimental_model
    Purified human intramelanosomal domains expressed in insect cells.
    limitations
    These variants retain activity; they should not be conflated with all albinism variants.
    nutrient_topic
    L-Tyrosine collection; species, compartment, exposure, co-substrates and manipulation remain explicit. · L-Tyrosine
    plain_language
    Reduced pigment synthesis can reflect enzyme structure rather than low tyrosine.
    primary_references
    Albinism-causing mutations in recombinant human tyrosinase alter intrinsic enzymatic activity. · 2014 · https://pubmed.ncbi.nlm.nih.gov/24392141/ · DOI 10.1371/journal.pone.0084494
    trigger_kind
    machinery_impairment Imported condition classification; unverified.

    L-Tyrosine: catecholamines, thyroid chemistry, pigment, metabolism and cross-nutrient mechanisms (2026-09-19) · lines 164–170

    AI-assisted research curation; primary references, access levels and experimental limitations individually identified. Not publisher full text. · supports · Purified human intramelanosomal domains expressed in insect cells. · source_derived_draft · unverified_draft

    ## l-tyrosine-tyr-variants Reduced pigment synthesis can reflect enzyme structure rather than low tyrosine. Human TYR R422Q and R422W variants had lower activity and temperature sensitivity compared with wild type. Model: Purified human intramelanosomal domains expressed in insect cells. Limitations: These variants retain activity; they should not be conflated with all albinism variants. Evidence access: Primary abstract Albinism-causing mutations in recombinant human tyrosinase alter intrinsic enzymatic activity. · 2014 · https://pubmed.ncbi.nlm.nih.gov/24392141/ · DOI 10.1371/journal.pone.0084494
    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