Component

Phosphatidylinositol (PI)

Phosphatidylinositol (PI). Species, exposure and limitations are retained in each linked claim.

5 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. Human placental phosphatidylinositol synthase used myo-inositol and CDP-diacylglycerol to form phosphatidylinositol.

    CDIPT (human phosphatidylinositol synthase) → Phosphatidylinositol (PI) source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/inositol-research/8110188.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "c05bb5272b443bde4f99d4af375d31988a4812150450d6c4462059a59aa8a09e", "start_char": 0, "end_char": 940, "text_sha256": "c05bb5272b443bde4f99d4af375d31988a4812150450d6c4462059a59aa8a09e"}
    experimental_model
    Purification and kinetics of placental PI synthase
    exposure
    Substrate and ion titrations
    limitations
    Assay optima and inhibitory concentrations are not dietary advice or proof of in vivo nutrient competition.
    nutrient_topic
    Inositol research collection; topical membership is not evidence of a direct dietary effect. · Inositol (stereoisomer family)
    organism
    Homo sapiens
    plain_language
    This step attaches the inositol head group to a membrane lipid.
    primary_references
    [ino-p8110188] Purification and characterization of phosphatidylinositol synthase from human placenta. (1994). https://pubmed.ncbi.nlm.nih.gov/8110188/ DOI: 10.1042/bj2970517
    tissue_or_cell_type
    Placental microsomal enzyme

    Inositol: synthesis, signaling, mineral interactions and conditional deficiency (2026-09-17) · lines 496–507

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Purification and kinetics of placental PI synthase · source_derived_draft · unverified_draft

    ### ino-cdipt-synthesis Human placental phosphatidylinositol synthase used myo-inositol and CDP-diacylglycerol to form phosphatidylinositol. Condition category: normal nutrient_topic: Inositol research collection; topical membership is not evidence of a direct dietary effect. plain_language: This step attaches the inositol head group to a membrane lipid. organism: Homo sapiens tissue_or_cell_type: Placental microsomal enzyme experimental_model: Purification and kinetics of placental PI synthase limitations: Assay optima and inhibitory concentrations are not dietary advice or proof of in vivo nutrient competition. exposure: Substrate and ion titrations evidence_span: {"source_cache": "artifacts/inositol-research/8110188.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "c05bb5272b443bde4f99d4af375d31988a4812150450d6c4462059a59aa8a09e", "start_char": 0, "end_char": 940, "text_sha256": "c05bb5272b443bde4f99d4af375d31988a4812150450d6c4462059a59aa8a09e"} [ino-p8110188] Purification and characterization of phosphatidylinositol synthase from human placenta. (1994). https://pubmed.ncbi.nlm.nih.gov/8110188/ DOI: 10.1042/bj2970517
    Complete structured claim and evidence

  2. Recombinant human PI4K230, now designated PI4KA, showed phosphatidylinositol 4-kinase activity.

    PI4KA (human phosphatidylinositol 4-kinase alpha) → Phosphatidylinositol (PI) source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/inositol-research/10101268.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "fa5bbd801387ed6401fcba3b21ddc260a21a089c33818db5abcfea346b3db5d0", "start_char": 0, "end_char": 1101, "text_sha256": "fa5bbd801387ed6401fcba3b21ddc260a21a089c33818db5abcfea346b3db5d0"}
    experimental_model
    Recombinant human PI4K230 enzyme characterization
    exposure
    ATP-dependent kinase assays
    limitations
    An enzyme reaction does not establish that free inositol supplementation increases signaling.
    nutrient_topic
    Inositol research collection; topical membership is not evidence of a direct dietary effect. · Inositol (stereoisomer family)
    organism
    Human protein expressed in Sf9 cells
    plain_language
    An enzyme adds a phosphate at position 4 of the PI head group.
    primary_references
    [ino-p10101268] Functional expression and characterisation of a new human phosphatidylinositol 4-kinase PI4K230. (1999). https://pubmed.ncbi.nlm.nih.gov/10101268/ DOI: 10.1016/s1388-1981(99)00029-3
    tissue_or_cell_type
    Recombinant PI4KA

    Inositol: synthesis, signaling, mineral interactions and conditional deficiency (2026-09-17) · lines 561–572

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Recombinant human PI4K230 enzyme characterization · source_derived_draft · unverified_draft

    ### ino-pi4ka-pi4p Recombinant human PI4K230, now designated PI4KA, showed phosphatidylinositol 4-kinase activity. Condition category: normal nutrient_topic: Inositol research collection; topical membership is not evidence of a direct dietary effect. plain_language: An enzyme adds a phosphate at position 4 of the PI head group. organism: Human protein expressed in Sf9 cells tissue_or_cell_type: Recombinant PI4KA experimental_model: Recombinant human PI4K230 enzyme characterization limitations: An enzyme reaction does not establish that free inositol supplementation increases signaling. exposure: ATP-dependent kinase assays evidence_span: {"source_cache": "artifacts/inositol-research/10101268.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "fa5bbd801387ed6401fcba3b21ddc260a21a089c33818db5abcfea346b3db5d0", "start_char": 0, "end_char": 1101, "text_sha256": "fa5bbd801387ed6401fcba3b21ddc260a21a089c33818db5abcfea346b3db5d0"} [ino-p10101268] Functional expression and characterisation of a new human phosphatidylinositol 4-kinase PI4K230. (1999). https://pubmed.ncbi.nlm.nih.gov/10101268/ DOI: 10.1016/s1388-1981(99)00029-3
    Complete structured claim and evidence

  3. Despite severely reduced brain myo-inositol, measured brain phosphatidylinositol was not decreased in SMIT1-null mice.

    Mouse Slc5a3 (SMIT1) → Phosphatidylinositol (PI) source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    machinery_impairment Imported condition classification; unverified.
    evidence_span
    {"source_cache": "artifacts/inositol-research/15110328.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "efa2c78237254c73512bf946f2600f4ead3f1e510cda84a06327906d4663d3ee", "start_char": 0, "end_char": 1202, "text_sha256": "efa2c78237254c73512bf946f2600f4ead3f1e510cda84a06327906d4663d3ee"}
    experimental_model
    Transporter knockout and brain chemical analysis
    exposure
    SMIT1-null mice
    limitations
    Severe genetic transport failure is not dietary deficiency. Unchanged total PI does not rule out local phosphoinositide abnormalities. An indexed erratum exists (10.1016/j.ymgme.2004.06.012); its content was not retrievable during this curation, so these findings remain provisional reports from the indexed original abstract.
    nutrient_topic
    Inositol research collection; topical membership is not evidence of a direct dietary effect. · Inositol (stereoisomer family)
    organism
    Mus musculus
    plain_language
    The free pool and the total membrane-lipid pool did not fall together.
    primary_references
    [ino-p15110328] Phosphoinositide deficiency due to inositol depletion is not a mechanism of lithium action in brain. (2004). https://pubmed.ncbi.nlm.nih.gov/15110328/ DOI: 10.1016/j.ymgme.2004.02.002
    tissue_or_cell_type
    Brain
    trigger_kind
    machinery_impairment Imported condition classification; unverified.

    Inositol: synthesis, signaling, mineral interactions and conditional deficiency (2026-09-17) · lines 444–455

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Transporter knockout and brain chemical analysis · source_derived_draft · unverified_draft

    ### ino-smit1-pi-preserved Despite severely reduced brain myo-inositol, measured brain phosphatidylinositol was not decreased in SMIT1-null mice. Condition category: machinery_impairment nutrient_topic: Inositol research collection; topical membership is not evidence of a direct dietary effect. plain_language: The free pool and the total membrane-lipid pool did not fall together. organism: Mus musculus tissue_or_cell_type: Brain experimental_model: Transporter knockout and brain chemical analysis limitations: Severe genetic transport failure is not dietary deficiency. Unchanged total PI does not rule out local phosphoinositide abnormalities. An indexed erratum exists (10.1016/j.ymgme.2004.06.012); its content was not retrievable during this curation, so these findings remain provisional reports from the indexed original abstract. exposure: SMIT1-null mice evidence_span: {"source_cache": "artifacts/inositol-research/15110328.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "efa2c78237254c73512bf946f2600f4ead3f1e510cda84a06327906d4663d3ee", "start_char": 0, "end_char": 1202, "text_sha256": "efa2c78237254c73512bf946f2600f4ead3f1e510cda84a06327906d4663d3ee"} [ino-p15110328] Phosphoinositide deficiency due to inositol depletion is not a mechanism of lithium action in brain. (2004). https://pubmed.ncbi.nlm.nih.gov/15110328/ DOI: 10.1016/j.ymgme.2004.02.002
    Complete structured claim and evidence

Where it participates (unsigned role)

  1. ARV1-containing GPI-GnT used PI more efficiently than the ARV1-less complex in vitro.

    ARV1 (human ER membrane protein) → Human GPI N-acetylglucosaminyltransferase complex source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/inositol-research/40378954.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "858f4bd2342d09239e21945d3d83aab06d84f33da26cb788e3ac091b713a1917", "start_char": 0, "end_char": 1260, "text_sha256": "858f4bd2342d09239e21945d3d83aab06d84f33da26cb788e3ac091b713a1917"}
    experimental_model
    Human-cell gene perturbation and isolated-complex activity
    exposure
    ARV1/PIGQ association and PI utilization
    limitations
    The ring-shaped assembly was AlphaFold-predicted, not an experimentally resolved structure. Effects on GPI-anchored proteins varied by cell and protein.
    nutrient_topic
    Inositol research collection; topical membership is not evidence of a direct dietary effect. · Inositol (stereoisomer family)
    organism
    Homo sapiens
    plain_language
    The anchor pathway depends on substrate handling, not only the total amount of inositol.
    primary_references
    [ino-p40378954] ARV1 is a component of the enzyme initiating glycosylphosphatidylinositol biosynthesis. (2025). https://pubmed.ncbi.nlm.nih.gov/40378954/ DOI: 10.1016/j.jbc.2025.110236
    tissue_or_cell_type
    Fibroblasts, HEK293 cells and ER enzyme complex

    Inositol: synthesis, signaling, mineral interactions and conditional deficiency (2026-09-17) · lines 1146–1157

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Human-cell gene perturbation and isolated-complex activity · source_derived_draft · unverified_draft

    ### ino-arv1-pi ARV1-containing GPI-GnT used PI more efficiently than the ARV1-less complex in vitro. Condition category: normal nutrient_topic: Inositol research collection; topical membership is not evidence of a direct dietary effect. plain_language: The anchor pathway depends on substrate handling, not only the total amount of inositol. organism: Homo sapiens tissue_or_cell_type: Fibroblasts, HEK293 cells and ER enzyme complex experimental_model: Human-cell gene perturbation and isolated-complex activity limitations: The ring-shaped assembly was AlphaFold-predicted, not an experimentally resolved structure. Effects on GPI-anchored proteins varied by cell and protein. exposure: ARV1/PIGQ association and PI utilization evidence_span: {"source_cache": "artifacts/inositol-research/40378954.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "858f4bd2342d09239e21945d3d83aab06d84f33da26cb788e3ac091b713a1917", "start_char": 0, "end_char": 1260, "text_sha256": "858f4bd2342d09239e21945d3d83aab06d84f33da26cb788e3ac091b713a1917"} [ino-p40378954] ARV1 is a component of the enzyme initiating glycosylphosphatidylinositol biosynthesis. (2025). https://pubmed.ncbi.nlm.nih.gov/40378954/ DOI: 10.1016/j.jbc.2025.110236
    Complete structured claim and evidence

  2. GPI N-acetylglucosaminyltransferase initiates anchor biosynthesis by transferring GlcNAc from UDP-GlcNAc to PI.

    Human GPI N-acetylglucosaminyltransferase complex → N-acetylglucosaminyl-phosphatidylinositol (GlcNAc-PI) source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/inositol-research/40378954.fulltext.txt", "locator": "Exact primary full-text span; zero-based, end-exclusive Unicode character offsets", "file_sha256": "3cc2c3ec38a92b3f125ade893ea74380cd41dab129c560dcca339f6f9dae1ed8", "start_char": 602, "end_char": 1102, "text_sha256": "efb80e58245431f0e571ea2fbf380914ac09fe0c07c148fd9a062f5e744166e4"}
    experimental_model
    Human-cell gene perturbation and isolated-complex activity
    exposure
    ARV1/PIGQ association and PI utilization
    limitations
    The ring-shaped assembly was AlphaFold-predicted, not an experimentally resolved structure. Effects on GPI-anchored proteins varied by cell and protein.
    nutrient_topic
    Inositol research collection; topical membership is not evidence of a direct dietary effect. · Inositol (stereoisomer family)
    organism
    Homo sapiens
    plain_language
    Inositol-containing membrane lipid is a starting material for anchors that hold proteins at the cell surface.
    primary_references
    [ino-p40378954] ARV1 is a component of the enzyme initiating glycosylphosphatidylinositol biosynthesis. (2025). https://pubmed.ncbi.nlm.nih.gov/40378954/ DOI: 10.1016/j.jbc.2025.110236
    tissue_or_cell_type
    Fibroblasts, HEK293 cells and ER enzyme complex

    Inositol: synthesis, signaling, mineral interactions and conditional deficiency (2026-09-17) · lines 1120–1131

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Human-cell gene perturbation and isolated-complex activity · source_derived_draft · unverified_draft

    ### ino-gpi-initiation GPI N-acetylglucosaminyltransferase initiates anchor biosynthesis by transferring GlcNAc from UDP-GlcNAc to PI. Condition category: normal nutrient_topic: Inositol research collection; topical membership is not evidence of a direct dietary effect. plain_language: Inositol-containing membrane lipid is a starting material for anchors that hold proteins at the cell surface. organism: Homo sapiens tissue_or_cell_type: Fibroblasts, HEK293 cells and ER enzyme complex experimental_model: Human-cell gene perturbation and isolated-complex activity limitations: The ring-shaped assembly was AlphaFold-predicted, not an experimentally resolved structure. Effects on GPI-anchored proteins varied by cell and protein. exposure: ARV1/PIGQ association and PI utilization evidence_span: {"source_cache": "artifacts/inositol-research/40378954.fulltext.txt", "locator": "Exact primary full-text span; zero-based, end-exclusive Unicode character offsets", "file_sha256": "3cc2c3ec38a92b3f125ade893ea74380cd41dab129c560dcca339f6f9dae1ed8", "start_char": 602, "end_char": 1102, "text_sha256": "efb80e58245431f0e571ea2fbf380914ac09fe0c07c148fd9a062f5e744166e4"} [ino-p40378954] ARV1 is a component of the enzyme initiating glycosylphosphatidylinositol biosynthesis. (2025). https://pubmed.ncbi.nlm.nih.gov/40378954/ DOI: 10.1016/j.jbc.2025.110236
    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