Component

Diphosphoinositol pentakisphosphate kinase family

Diphosphoinositol pentakisphosphate kinase family. 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 it acts on

  1. PPIP5K knockout reduced XPR1-dependent phosphate efflux; wild-type PPIP5K1 rescued efflux whereas kinase-dead PPIP5K1 did not.

    Diphosphoinositol pentakisphosphate kinase family → Cellular inorganic phosphate export source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    machinery_impairment Imported condition classification; unverified.
    evidence_span
    {"source_cache": "artifacts/inositol-research/32019887.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "bb7637b9a327b1cba07716bbed5da8a3f32a3ac00c9fff70d23ada1a736d3d18", "start_char": 0, "end_char": 2004, "text_sha256": "bb7637b9a327b1cba07716bbed5da8a3f32a3ac00c9fff70d23ada1a736d3d18"}
    experimental_model
    Binding, knockout and rescue experiments
    exposure
    PPIP5K or XPR1 deletion, kinase rescue and pyrophosphate analog delivery
    limitations
    Cell assays establish a transport-regulation mechanism, not benefits of oral inositol or increased bone mineralization.
    nutrient_topic
    Inositol research collection; topical membership is not evidence of a direct dietary effect. · Inositol (stereoisomer family)
    organism
    Human cultured cells including Saos-2 osteosarcoma cells
    plain_language
    The exporter needed the signal-generating activity, not simply the presence of the protein.
    primary_references
    [ino-p32019887] Control of XPR1-dependent cellular phosphate efflux by InsP8 is an exemplar for functionally-exclusive inositol pyrophosphate signaling. (2020). https://pubmed.ncbi.nlm.nih.gov/32019887/ DOI: 10.1073/pnas.1908830117
    tissue_or_cell_type
    Cellular phosphate transport
    trigger_kind
    machinery_impairment Imported condition classification; unverified.

    Inositol: synthesis, signaling, mineral interactions and conditional deficiency (2026-09-17) · lines 886–897

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Binding, knockout and rescue experiments · source_derived_draft · unverified_draft

    ### ino-ppip5k-export PPIP5K knockout reduced XPR1-dependent phosphate efflux; wild-type PPIP5K1 rescued efflux whereas kinase-dead PPIP5K1 did not. Condition category: machinery_impairment nutrient_topic: Inositol research collection; topical membership is not evidence of a direct dietary effect. plain_language: The exporter needed the signal-generating activity, not simply the presence of the protein. organism: Human cultured cells including Saos-2 osteosarcoma cells tissue_or_cell_type: Cellular phosphate transport experimental_model: Binding, knockout and rescue experiments limitations: Cell assays establish a transport-regulation mechanism, not benefits of oral inositol or increased bone mineralization. exposure: PPIP5K or XPR1 deletion, kinase rescue and pyrophosphate analog delivery evidence_span: {"source_cache": "artifacts/inositol-research/32019887.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "bb7637b9a327b1cba07716bbed5da8a3f32a3ac00c9fff70d23ada1a736d3d18", "start_char": 0, "end_char": 2004, "text_sha256": "bb7637b9a327b1cba07716bbed5da8a3f32a3ac00c9fff70d23ada1a736d3d18"} [ino-p32019887] Control of XPR1-dependent cellular phosphate efflux by InsP8 is an exemplar for functionally-exclusive inositol pyrophosphate signaling. (2020). https://pubmed.ncbi.nlm.nih.gov/32019887/ DOI: 10.1073/pnas.1908830117
    Complete structured claim and evidence

  2. PPIP5K kinase activity converts 5-InsP7 to 1,5-InsP8.

    Diphosphoinositol pentakisphosphate kinase family → 5-diphosphoinositol pentakisphosphate (5-InsP7) source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/inositol-research/28126903.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "6f5c96ed7d02591d5fe475d0e26aa2f21dc93f0c86c12998debb417f98254d2f", "start_char": 0, "end_char": 1981, "text_sha256": "6f5c96ed7d02591d5fe475d0e26aa2f21dc93f0c86c12998debb417f98254d2f"}
    experimental_model
    Cellular phosphate withdrawal/repletion and bifunctional enzyme kinetics
    exposure
    Phosphate availability and PPIP5K kinase/phosphatase assays
    limitations
    Cell-culture nutrient withdrawal is not a measured human dietary threshold; PPIP5K isoforms are not identical.
    nutrient_topic
    Inositol research collection; topical membership is not evidence of a direct dietary effect. · Inositol (stereoisomer family)
    organism
    Human HCT116 cells and human PPIP5K proteins
    plain_language
    A further phosphorylation step creates another distinct phosphate signal.
    primary_references
    [ino-p28126903] The Significance of the Bifunctional Kinase/Phosphatase Activities of Diphosphoinositol Pentakisphosphate Kinases (PPIP5Ks) for Coupling Inositol Pyrophosphate Cell Signaling to Cellular Phosphate Homeostasis. (2017). https://pubmed.ncbi.nlm.nih.gov/28126903/ DOI: 10.1074/jbc.m116.765743
    tissue_or_cell_type
    Intestinal tumor-derived cell line; purified enzymes

    Inositol: synthesis, signaling, mineral interactions and conditional deficiency (2026-09-17) · lines 808–819

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Cellular phosphate withdrawal/repletion and bifunctional enzyme kinetics · source_derived_draft · unverified_draft

    ### ino-ppip5k-ip8 PPIP5K kinase activity converts 5-InsP7 to 1,5-InsP8. Condition category: normal nutrient_topic: Inositol research collection; topical membership is not evidence of a direct dietary effect. plain_language: A further phosphorylation step creates another distinct phosphate signal. organism: Human HCT116 cells and human PPIP5K proteins tissue_or_cell_type: Intestinal tumor-derived cell line; purified enzymes experimental_model: Cellular phosphate withdrawal/repletion and bifunctional enzyme kinetics limitations: Cell-culture nutrient withdrawal is not a measured human dietary threshold; PPIP5K isoforms are not identical. exposure: Phosphate availability and PPIP5K kinase/phosphatase assays evidence_span: {"source_cache": "artifacts/inositol-research/28126903.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "6f5c96ed7d02591d5fe475d0e26aa2f21dc93f0c86c12998debb417f98254d2f", "start_char": 0, "end_char": 1981, "text_sha256": "6f5c96ed7d02591d5fe475d0e26aa2f21dc93f0c86c12998debb417f98254d2f"} [ino-p28126903] The Significance of the Bifunctional Kinase/Phosphatase Activities of Diphosphoinositol Pentakisphosphate Kinases (PPIP5Ks) for Coupling Inositol Pyrophosphate Cell Signaling to Cellular Phosphate Homeostasis. (2017). https://pubmed.ncbi.nlm.nih.gov/28126903/ DOI: 10.1074/jbc.m116.765743
    Complete structured claim and evidence

  3. PPIP5K proteins also possess InsP8 phosphatase activity, opposing their kinase reaction.

    Diphosphoinositol pentakisphosphate kinase family → 1,5-bisdiphosphoinositol tetrakisphosphate (1,5-InsP8) source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/inositol-research/28126903.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "6f5c96ed7d02591d5fe475d0e26aa2f21dc93f0c86c12998debb417f98254d2f", "start_char": 0, "end_char": 1981, "text_sha256": "6f5c96ed7d02591d5fe475d0e26aa2f21dc93f0c86c12998debb417f98254d2f"}
    experimental_model
    Cellular phosphate withdrawal/repletion and bifunctional enzyme kinetics
    exposure
    Phosphate availability and PPIP5K kinase/phosphatase assays
    limitations
    Cell-culture nutrient withdrawal is not a measured human dietary threshold; PPIP5K isoforms are not identical.
    nutrient_topic
    Inositol research collection; topical membership is not evidence of a direct dietary effect. · Inositol (stereoisomer family)
    organism
    Human HCT116 cells and human PPIP5K proteins
    plain_language
    The same protein family can build and break down the signal.
    primary_references
    [ino-p28126903] The Significance of the Bifunctional Kinase/Phosphatase Activities of Diphosphoinositol Pentakisphosphate Kinases (PPIP5Ks) for Coupling Inositol Pyrophosphate Cell Signaling to Cellular Phosphate Homeostasis. (2017). https://pubmed.ncbi.nlm.nih.gov/28126903/ DOI: 10.1074/jbc.m116.765743
    tissue_or_cell_type
    Intestinal tumor-derived cell line; purified enzymes

    Inositol: synthesis, signaling, mineral interactions and conditional deficiency (2026-09-17) · lines 821–832

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Cellular phosphate withdrawal/repletion and bifunctional enzyme kinetics · source_derived_draft · unverified_draft

    ### ino-ppip5k-reverse PPIP5K proteins also possess InsP8 phosphatase activity, opposing their kinase reaction. Condition category: normal nutrient_topic: Inositol research collection; topical membership is not evidence of a direct dietary effect. plain_language: The same protein family can build and break down the signal. organism: Human HCT116 cells and human PPIP5K proteins tissue_or_cell_type: Intestinal tumor-derived cell line; purified enzymes experimental_model: Cellular phosphate withdrawal/repletion and bifunctional enzyme kinetics limitations: Cell-culture nutrient withdrawal is not a measured human dietary threshold; PPIP5K isoforms are not identical. exposure: Phosphate availability and PPIP5K kinase/phosphatase assays evidence_span: {"source_cache": "artifacts/inositol-research/28126903.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "6f5c96ed7d02591d5fe475d0e26aa2f21dc93f0c86c12998debb417f98254d2f", "start_char": 0, "end_char": 1981, "text_sha256": "6f5c96ed7d02591d5fe475d0e26aa2f21dc93f0c86c12998debb417f98254d2f"} [ino-p28126903] The Significance of the Bifunctional Kinase/Phosphatase Activities of Diphosphoinositol Pentakisphosphate Kinases (PPIP5Ks) for Coupling Inositol Pyrophosphate Cell Signaling to Cellular Phosphate Homeostasis. (2017). https://pubmed.ncbi.nlm.nih.gov/28126903/ DOI: 10.1074/jbc.m116.765743
    Complete structured claim and evidence

What acts on it

  1. Inorganic phosphate inhibited PPIP5K InsP8 phosphatase activities by approximately 40–90% across 0–1 mM in the reported assays.

    Inorganic phosphate → Diphosphoinositol pentakisphosphate kinase family source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/inositol-research/28126903.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "6f5c96ed7d02591d5fe475d0e26aa2f21dc93f0c86c12998debb417f98254d2f", "start_char": 0, "end_char": 1981, "text_sha256": "6f5c96ed7d02591d5fe475d0e26aa2f21dc93f0c86c12998debb417f98254d2f"}
    experimental_model
    Cellular phosphate withdrawal/repletion and bifunctional enzyme kinetics
    exposure
    Phosphate availability and PPIP5K kinase/phosphatase assays
    limitations
    Cell-culture nutrient withdrawal is not a measured human dietary threshold; PPIP5K isoforms are not identical.
    nutrient_topic
    Inositol research collection; topical membership is not evidence of a direct dietary effect. · Inositol (stereoisomer family)
    organism
    Human HCT116 cells and human PPIP5K proteins
    plain_language
    Phosphate availability can slow destruction of the inositol-pyrophosphate signal.
    primary_references
    [ino-p28126903] The Significance of the Bifunctional Kinase/Phosphatase Activities of Diphosphoinositol Pentakisphosphate Kinases (PPIP5Ks) for Coupling Inositol Pyrophosphate Cell Signaling to Cellular Phosphate Homeostasis. (2017). https://pubmed.ncbi.nlm.nih.gov/28126903/ DOI: 10.1074/jbc.m116.765743
    tissue_or_cell_type
    Intestinal tumor-derived cell line; purified enzymes

    Inositol: synthesis, signaling, mineral interactions and conditional deficiency (2026-09-17) · lines 834–845

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Cellular phosphate withdrawal/repletion and bifunctional enzyme kinetics · source_derived_draft · unverified_draft

    ### ino-pi-ppip-phosphatase Inorganic phosphate inhibited PPIP5K InsP8 phosphatase activities by approximately 40–90% across 0–1 mM in the reported assays. Condition category: normal nutrient_topic: Inositol research collection; topical membership is not evidence of a direct dietary effect. plain_language: Phosphate availability can slow destruction of the inositol-pyrophosphate signal. organism: Human HCT116 cells and human PPIP5K proteins tissue_or_cell_type: Intestinal tumor-derived cell line; purified enzymes experimental_model: Cellular phosphate withdrawal/repletion and bifunctional enzyme kinetics limitations: Cell-culture nutrient withdrawal is not a measured human dietary threshold; PPIP5K isoforms are not identical. exposure: Phosphate availability and PPIP5K kinase/phosphatase assays evidence_span: {"source_cache": "artifacts/inositol-research/28126903.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "6f5c96ed7d02591d5fe475d0e26aa2f21dc93f0c86c12998debb417f98254d2f", "start_char": 0, "end_char": 1981, "text_sha256": "6f5c96ed7d02591d5fe475d0e26aa2f21dc93f0c86c12998debb417f98254d2f"} [ino-p28126903] The Significance of the Bifunctional Kinase/Phosphatase Activities of Diphosphoinositol Pentakisphosphate Kinases (PPIP5Ks) for Coupling Inositol Pyrophosphate Cell Signaling to Cellular Phosphate Homeostasis. (2017). https://pubmed.ncbi.nlm.nih.gov/28126903/ DOI: 10.1074/jbc.m116.765743
    Complete structured claim and evidence

Where it participates (unsigned role)

  1. XPR1 or PPIP5K knockout reduced phosphate export and accelerated the mineralization endpoint in Saos-2 cells.

    XPR1 (human phosphate exporter) → Saos-2 cell mineralization source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    machinery_impairment Imported condition classification; unverified.
    evidence_span
    {"source_cache": "artifacts/inositol-research/32019887.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "bb7637b9a327b1cba07716bbed5da8a3f32a3ac00c9fff70d23ada1a736d3d18", "start_char": 0, "end_char": 2004, "text_sha256": "bb7637b9a327b1cba07716bbed5da8a3f32a3ac00c9fff70d23ada1a736d3d18"}
    experimental_model
    Binding, knockout and rescue experiments
    exposure
    PPIP5K or XPR1 deletion, kinase rescue and pyrophosphate analog delivery
    limitations
    Cell assays establish a transport-regulation mechanism, not benefits of oral inositol or increased bone mineralization.
    nutrient_topic
    Inositol research collection; topical membership is not evidence of a direct dietary effect. · Inositol (stereoisomer family)
    organism
    Human cultured cells including Saos-2 osteosarcoma cells
    plain_language
    Retaining phosphate changed mineral deposition in a bone-tumor cell model.
    primary_references
    [ino-p32019887] Control of XPR1-dependent cellular phosphate efflux by InsP8 is an exemplar for functionally-exclusive inositol pyrophosphate signaling. (2020). https://pubmed.ncbi.nlm.nih.gov/32019887/ DOI: 10.1073/pnas.1908830117
    tissue_or_cell_type
    Cellular phosphate transport
    trigger_kind
    machinery_impairment Imported condition classification; unverified.

    Inositol: synthesis, signaling, mineral interactions and conditional deficiency (2026-09-17) · lines 912–923

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Binding, knockout and rescue experiments · source_derived_draft · unverified_draft

    ### ino-xpr1-mineralization XPR1 or PPIP5K knockout reduced phosphate export and accelerated the mineralization endpoint in Saos-2 cells. Condition category: machinery_impairment nutrient_topic: Inositol research collection; topical membership is not evidence of a direct dietary effect. plain_language: Retaining phosphate changed mineral deposition in a bone-tumor cell model. organism: Human cultured cells including Saos-2 osteosarcoma cells tissue_or_cell_type: Cellular phosphate transport experimental_model: Binding, knockout and rescue experiments limitations: Cell assays establish a transport-regulation mechanism, not benefits of oral inositol or increased bone mineralization. exposure: PPIP5K or XPR1 deletion, kinase rescue and pyrophosphate analog delivery evidence_span: {"source_cache": "artifacts/inositol-research/32019887.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "bb7637b9a327b1cba07716bbed5da8a3f32a3ac00c9fff70d23ada1a736d3d18", "start_char": 0, "end_char": 2004, "text_sha256": "bb7637b9a327b1cba07716bbed5da8a3f32a3ac00c9fff70d23ada1a736d3d18"} [ino-p32019887] Control of XPR1-dependent cellular phosphate efflux by InsP8 is an exemplar for functionally-exclusive inositol pyrophosphate signaling. (2020). https://pubmed.ncbi.nlm.nih.gov/32019887/ DOI: 10.1073/pnas.1908830117
    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