Component

Tetrahydroxyborate / B(OH)4−

Tetrahydroxyborate / B(OH)4−. Species, exposure and limitations are retained in each linked claim.

6 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. A borate ester bridges two RG-II molecules in the isolated plant-wall dimer.

    Tetrahydroxyborate / B(OH)4− → Borate-diester-linked RG-II dimer source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/pectin-research/8798473.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "4435a2ce2789d98a56c321a69ee20acbcafbff021acf2543a0b9126ebaa375fe", "start_char": 0, "end_char": 1643, "text_sha256": "4435a2ce2789d98a56c321a69ee20acbcafbff021acf2543a0b9126ebaa375fe"}
    experimental_model
    Plant cell-wall isolation and in-vitro dimer chemistry
    exposure
    Isolated RG-II, boric acid and controlled pH
    limitations
    Plant structural chemistry is not a human pectin or boron supplementation mechanism.
    nutrient_topic
    Pectin research collection; topical membership is not evidence of a direct dietary effect. · Pectin, structurally heterogeneous plant polysaccharides
    organism
    Sycamore cell cultures and pea stems; purified plant polysaccharide
    plain_language
    Boron is part of a plant pectin cross-link.
    primary_references
    [pectin-p8798473] Rhamnogalacturonan-II, a pectic polysaccharide in the walls of growing plant cell, forms a dimer that is covalently cross-linked by a borate ester. In vitro conditions for the formation and hydrolysis of the dimer. (1996). https://pubmed.ncbi.nlm.nih.gov/8798473/ DOI: 10.1074/jbc.271.37.22923
    tissue_or_cell_type
    Plant cell wall

    Pectin: metabolism, signaling and nutrient connections (2026-09-17) · lines 334–345

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Plant cell-wall isolation and in-vitro dimer chemistry · source_derived_draft · unverified_draft

    ### pectin-borate-crosslink A borate ester bridges two RG-II molecules in the isolated plant-wall dimer. Condition category: normal nutrient_topic: Pectin research collection; topical membership is not evidence of a direct dietary effect. plain_language: Boron is part of a plant pectin cross-link. organism: Sycamore cell cultures and pea stems; purified plant polysaccharide tissue_or_cell_type: Plant cell wall experimental_model: Plant cell-wall isolation and in-vitro dimer chemistry limitations: Plant structural chemistry is not a human pectin or boron supplementation mechanism. exposure: Isolated RG-II, boric acid and controlled pH evidence_span: {"source_cache": "artifacts/pectin-research/8798473.abstract.txt", "locator": "Primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "4435a2ce2789d98a56c321a69ee20acbcafbff021acf2543a0b9126ebaa375fe", "start_char": 0, "end_char": 1643, "text_sha256": "4435a2ce2789d98a56c321a69ee20acbcafbff021acf2543a0b9126ebaa375fe"} [pectin-p8798473] Rhamnogalacturonan-II, a pectic polysaccharide in the walls of growing plant cell, forms a dimer that is covalently cross-linked by a borate ester. In vitro conditions for the formation and hydrolysis of the dimer. (1996). https://pubmed.ncbi.nlm.nih.gov/8798473/ DOI: 10.1074/jbc.271.37.22923
    Complete structured claim and evidence

Where it participates (unsigned role)

  1. Boron binding in the tested nucleotide series depended on suitable cis-diol groups, and NAD+ bound more strongly than NADH in the capillary-electrophoresis assay.

    NAD+ → Boron complex with NAD+ source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/boron-research/11420139.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "0792ce09223d7cf23f0d3fda6b793e6e3b9904abe2c1f934b96d50e3a0e8b703", "start_char": 0, "end_char": 1650, "text_sha256": "0792ce09223d7cf23f0d3fda6b793e6e3b9904abe2c1f934b96d50e3a0e8b703"}
    experimental_model
    Capillary electrophoresis of purified metabolites
    exposure
    Boron complexation under the reported assay conditions
    limitations
    Chemical affinity is not a demonstrated metabolic function or in-vivo occupancy. Rankings depend on assay and solution conditions.
    nutrient_topic
    Boron research collection; topical membership is not evidence of a direct dietary effect. · Boron
    organism
    Cell-free chemistry
    plain_language
    The arrangement of neighboring hydroxyl groups helps determine which nucleotide molecules can bind boron.
    primary_references
    [boron-p11420139] Diadenosine phosphates and S-adenosylmethionine: novel boron binding biomolecules detected by capillary electrophoresis. (2001). https://pubmed.ncbi.nlm.nih.gov/11420139/ DOI: 10.1016/s0304-4165(01)00130-1
    tissue_or_cell_type
    Aqueous assay; no tissue

    Boron: chemistry, nutrient interactions, low-intake studies and mechanistic uncertainties (2026-09-17) · lines 105–116

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Capillary electrophoresis of purified metabolites · source_derived_draft · unverified_draft

    ### boron-cis-diol-binding Boron binding in the tested nucleotide series depended on suitable cis-diol groups, and NAD+ bound more strongly than NADH in the capillary-electrophoresis assay. Condition category: normal nutrient_topic: Boron research collection; topical membership is not evidence of a direct dietary effect. plain_language: The arrangement of neighboring hydroxyl groups helps determine which nucleotide molecules can bind boron. organism: Cell-free chemistry tissue_or_cell_type: Aqueous assay; no tissue experimental_model: Capillary electrophoresis of purified metabolites limitations: Chemical affinity is not a demonstrated metabolic function or in-vivo occupancy. Rankings depend on assay and solution conditions. exposure: Boron complexation under the reported assay conditions evidence_span: {"source_cache": "artifacts/boron-research/11420139.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "0792ce09223d7cf23f0d3fda6b793e6e3b9904abe2c1f934b96d50e3a0e8b703", "start_char": 0, "end_char": 1650, "text_sha256": "0792ce09223d7cf23f0d3fda6b793e6e3b9904abe2c1f934b96d50e3a0e8b703"} [boron-p11420139] Diadenosine phosphates and S-adenosylmethionine: novel boron binding biomolecules detected by capillary electrophoresis. (2001). https://pubmed.ncbi.nlm.nih.gov/11420139/ DOI: 10.1016/s0304-4165(01)00130-1
    Complete structured claim and evidence

  2. In the 2013 replication study, 10 mM borate did not change the SLC4A11-associated intracellular-pH response during a sodium-free pulse, arguing against sodium–borate cotransport.

    Human SLC4A11 / NaBC1 → Cellular borate transport source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/boron-research/23864606.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "b35216315076720b687cb692519b340957bdadbeb1ce71ae26972aa301dd7df1", "start_char": 0, "end_char": 1835, "text_sha256": "b35216315076720b687cb692519b340957bdadbeb1ce71ae26972aa301dd7df1"}
    experimental_model
    HEK293 and NHE-deficient PS120 functional transport experiments
    exposure
    10 mM borate during sodium removal/readdition; comparison with control cells
    limitations
    Negative borate transport result applies to the tested assays. Sodium replacement and buffer chemistry were investigated; they do not establish a universal explanation of all discordant assays.
    nutrient_topic
    Boron research collection; topical membership is not evidence of a direct dietary effect. · Boron
    organism
    Human SLC4A11 in heterologous cells
    plain_language
    A direct follow-up failed to detect the borate transport predicted by the original model.
    primary_references
    [boron-p23864606] SLC4A11 is an EIPA-sensitive Na(+) permeable pHi regulator. (2013). https://pubmed.ncbi.nlm.nih.gov/23864606/ DOI: 10.1152/ajpcell.00056.2013
    tissue_or_cell_type
    Cell membrane; intracellular pH and sodium flux

    Boron: chemistry, nutrient interactions, low-intake studies and mechanistic uncertainties (2026-09-17) · lines 209–220

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · HEK293 and NHE-deficient PS120 functional transport experiments · source_derived_draft · unverified_draft

    ### boron-human-transport-negative-2013 In the 2013 replication study, 10 mM borate did not change the SLC4A11-associated intracellular-pH response during a sodium-free pulse, arguing against sodium–borate cotransport. Condition category: normal nutrient_topic: Boron research collection; topical membership is not evidence of a direct dietary effect. plain_language: A direct follow-up failed to detect the borate transport predicted by the original model. organism: Human SLC4A11 in heterologous cells tissue_or_cell_type: Cell membrane; intracellular pH and sodium flux experimental_model: HEK293 and NHE-deficient PS120 functional transport experiments limitations: Negative borate transport result applies to the tested assays. Sodium replacement and buffer chemistry were investigated; they do not establish a universal explanation of all discordant assays. exposure: 10 mM borate during sodium removal/readdition; comparison with control cells evidence_span: {"source_cache": "artifacts/boron-research/23864606.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "b35216315076720b687cb692519b340957bdadbeb1ce71ae26972aa301dd7df1", "start_char": 0, "end_char": 1835, "text_sha256": "b35216315076720b687cb692519b340957bdadbeb1ce71ae26972aa301dd7df1"} [boron-p23864606] SLC4A11 is an EIPA-sensitive Na(+) permeable pHi regulator. (2013). https://pubmed.ncbi.nlm.nih.gov/23864606/ DOI: 10.1152/ajpcell.00056.2013
    Complete structured claim and evidence

  3. Human SLC4A11 did not support borate-associated transport in Xenopus oocytes, whereas the plant NIP5;1 positive control did.

    Human SLC4A11 / NaBC1 → Cellular borate transport source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/boron-research/27558157.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "a49d680cd492460159d231e0c55b053b2143ce17aaa902c97c087e5985e78ebd", "start_char": 0, "end_char": 1823, "text_sha256": "a49d680cd492460159d231e0c55b053b2143ce17aaa902c97c087e5985e78ebd"}
    experimental_model
    Xenopus oocyte expression with plant positive control and HEK293 experiments
    exposure
    Borate-associated cell swelling; plant NIP5;1 positive control
    limitations
    Species of protein and expression host are distinct. The human negative result does not exclude borate transport by other species or unrelated proteins.
    nutrient_topic
    Boron research collection; topical membership is not evidence of a direct dietary effect. · Boron
    organism
    Human SLC4A11; Xenopus expression host
    plain_language
    A second study found no human SLC4A11 borate transport even though its positive control worked.
    primary_references
    [boron-p27558157] Functional assessment of SLC4A11, an integral membrane protein mutated in corneal dystrophies. (2016). https://pubmed.ncbi.nlm.nih.gov/27558157/ DOI: 10.1152/ajpcell.00078.2016
    tissue_or_cell_type
    Membrane transport assays

    Boron: chemistry, nutrient interactions, low-intake studies and mechanistic uncertainties (2026-09-17) · lines 222–233

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Xenopus oocyte expression with plant positive control and HEK293 experiments · source_derived_draft · unverified_draft

    ### boron-human-transport-negative-2016 Human SLC4A11 did not support borate-associated transport in Xenopus oocytes, whereas the plant NIP5;1 positive control did. Condition category: normal nutrient_topic: Boron research collection; topical membership is not evidence of a direct dietary effect. plain_language: A second study found no human SLC4A11 borate transport even though its positive control worked. organism: Human SLC4A11; Xenopus expression host tissue_or_cell_type: Membrane transport assays experimental_model: Xenopus oocyte expression with plant positive control and HEK293 experiments limitations: Species of protein and expression host are distinct. The human negative result does not exclude borate transport by other species or unrelated proteins. exposure: Borate-associated cell swelling; plant NIP5;1 positive control evidence_span: {"source_cache": "artifacts/boron-research/27558157.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "a49d680cd492460159d231e0c55b053b2143ce17aaa902c97c087e5985e78ebd", "start_char": 0, "end_char": 1823, "text_sha256": "a49d680cd492460159d231e0c55b053b2143ce17aaa902c97c087e5985e78ebd"} [boron-p27558157] Functional assessment of SLC4A11, an integral membrane protein mutated in corneal dystrophies. (2016). https://pubmed.ncbi.nlm.nih.gov/27558157/ DOI: 10.1152/ajpcell.00078.2016
    Complete structured claim and evidence

  4. The 2004 NaBC1 study assigned human SLC4A11 electrogenic, sodium-coupled borate transport.

    Human SLC4A11 / NaBC1 → Cellular borate transport source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/boron-research/15525507.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "741b5972d5af120759f4100701b1f450c620182ffe6585a1b5049533961a6abe", "start_char": 0, "end_char": 980, "text_sha256": "741b5972d5af120759f4100701b1f450c620182ffe6585a1b5049533961a6abe"}
    experimental_model
    Heterologous mammalian transporter expression and functional assays
    exposure
    Borate exposure with NaBC1 overexpression or knockdown
    limitations
    The borate-transport assignment is disputed by later direct experiments. This historical result remains visible as a genuine literature conflict, not accepted transporter annotation.
    nutrient_topic
    Boron research collection; topical membership is not evidence of a direct dietary effect. · Boron
    organism
    Human SLC4A11 expressed in experimental cells
    plain_language
    The original paper called SLC4A11 a borate transporter; later studies challenged this assignment.
    primary_references
    [boron-p15525507] NaBC1 is a ubiquitous electrogenic Na+ -coupled borate transporter essential for cellular boron homeostasis and cell growth and proliferation. (2004). https://pubmed.ncbi.nlm.nih.gov/15525507/ DOI: 10.1016/j.molcel.2004.09.030
    tissue_or_cell_type
    Membrane transport assays

    Boron: chemistry, nutrient interactions, low-intake studies and mechanistic uncertainties (2026-09-17) · lines 196–207

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Heterologous mammalian transporter expression and functional assays · source_derived_draft · unverified_draft

    ### boron-human-transport-original The 2004 NaBC1 study assigned human SLC4A11 electrogenic, sodium-coupled borate transport. Condition category: normal nutrient_topic: Boron research collection; topical membership is not evidence of a direct dietary effect. plain_language: The original paper called SLC4A11 a borate transporter; later studies challenged this assignment. organism: Human SLC4A11 expressed in experimental cells tissue_or_cell_type: Membrane transport assays experimental_model: Heterologous mammalian transporter expression and functional assays limitations: The borate-transport assignment is disputed by later direct experiments. This historical result remains visible as a genuine literature conflict, not accepted transporter annotation. exposure: Borate exposure with NaBC1 overexpression or knockdown evidence_span: {"source_cache": "artifacts/boron-research/15525507.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "741b5972d5af120759f4100701b1f450c620182ffe6585a1b5049533961a6abe", "start_char": 0, "end_char": 980, "text_sha256": "741b5972d5af120759f4100701b1f450c620182ffe6585a1b5049533961a6abe"} [boron-p15525507] NaBC1 is a ubiquitous electrogenic Na+ -coupled borate transporter essential for cellular boron homeostasis and cell growth and proliferation. (2004). https://pubmed.ncbi.nlm.nih.gov/15525507/ DOI: 10.1016/j.molcel.2004.09.030
    Complete structured claim and evidence

  5. S-adenosylmethionine formed a boron complex in capillary-electrophoresis experiments and ranked among the strongest ligands tested.

    S-Adenosyl-L-methionine → Boron complex with S-adenosylmethionine source_derived_draftungraded
    Experimental context and source evidence
    evidence_span
    {"source_cache": "artifacts/boron-research/11420139.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "0792ce09223d7cf23f0d3fda6b793e6e3b9904abe2c1f934b96d50e3a0e8b703", "start_char": 0, "end_char": 1650, "text_sha256": "0792ce09223d7cf23f0d3fda6b793e6e3b9904abe2c1f934b96d50e3a0e8b703"}
    experimental_model
    Capillary electrophoresis of purified metabolites
    exposure
    Boron complexation under the reported assay conditions
    limitations
    Chemical affinity is not a demonstrated metabolic function or in-vivo occupancy. Rankings depend on assay and solution conditions.
    nutrient_topic
    Boron research collection; topical membership is not evidence of a direct dietary effect. · Boron
    organism
    Cell-free chemistry
    plain_language
    Boron can attach to SAM in a test tube; this does not show that it supplies methyl groups or improves methylation.
    primary_references
    [boron-p11420139] Diadenosine phosphates and S-adenosylmethionine: novel boron binding biomolecules detected by capillary electrophoresis. (2001). https://pubmed.ncbi.nlm.nih.gov/11420139/ DOI: 10.1016/s0304-4165(01)00130-1
    tissue_or_cell_type
    Aqueous assay; no tissue

    Boron: chemistry, nutrient interactions, low-intake studies and mechanistic uncertainties (2026-09-17) · lines 92–103

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Capillary electrophoresis of purified metabolites · source_derived_draft · unverified_draft

    ### boron-sam-binding S-adenosylmethionine formed a boron complex in capillary-electrophoresis experiments and ranked among the strongest ligands tested. Condition category: normal nutrient_topic: Boron research collection; topical membership is not evidence of a direct dietary effect. plain_language: Boron can attach to SAM in a test tube; this does not show that it supplies methyl groups or improves methylation. organism: Cell-free chemistry tissue_or_cell_type: Aqueous assay; no tissue experimental_model: Capillary electrophoresis of purified metabolites limitations: Chemical affinity is not a demonstrated metabolic function or in-vivo occupancy. Rankings depend on assay and solution conditions. exposure: Boron complexation under the reported assay conditions evidence_span: {"source_cache": "artifacts/boron-research/11420139.abstract.txt", "locator": "Exact primary indexed abstract; zero-based, end-exclusive Unicode character offsets", "file_sha256": "0792ce09223d7cf23f0d3fda6b793e6e3b9904abe2c1f934b96d50e3a0e8b703", "start_char": 0, "end_char": 1650, "text_sha256": "0792ce09223d7cf23f0d3fda6b793e6e3b9904abe2c1f934b96d50e3a0e8b703"} [boron-p11420139] Diadenosine phosphates and S-adenosylmethionine: novel boron binding biomolecules detected by capillary electrophoresis. (2001). https://pubmed.ncbi.nlm.nih.gov/11420139/ DOI: 10.1016/s0304-4165(01)00130-1
    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.

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