Component

Renal outer medullary potassium channel / KCNJ1

ROMK / Kir1.1 potassium channel encoded by KCNJ1. Native-channel measurements do not necessarily resolve splice isoforms.

8 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. Romk-null mice had reduced, but persisting, TAL NaCl absorption by micropuncture; the companion study demonstrated loss of native apical small-conductance K channels.

    Renal outer medullary potassium channel / KCNJ1 → Renal sodium reabsorption source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    machinery_impairment Imported condition classification; unverified.
    cross_nutrient
    Loss of potassium-channel machinery impairs sodium/chloride recovery.
    evidence_location
    Lorenz primary abstract: micropuncture; Lu Results: TAL patch-clamp.
    experimental_model
    Pan-Romk deletion; micropuncture and companion patch-clamp studies
    limitations
    Hydronephrosis, developmental disease and compensatory transport complicate whole-kidney endpoints.
    nutrient_topic
    Potassium research collection; topical membership is not evidence of a direct dietary effect. · Potassium
    organism
    Mus musculus
    plain_language
    ROMK-mediated potassium recycling supports loop salt recovery, while residual salt transport survives its deletion.
    primary_references
    [lorenz-2002-romk-tal] Impaired renal NaCl absorption in mice lacking the ROMK potassium channel, a model for type II Bartter's syndrome (2002). https://pubmed.ncbi.nlm.nih.gov/12122007/ DOI: 10.1074/jbc.M205627200 [lu-2002-romk-null] Absence of small conductance K+ channel (SK) activity in apical membranes of thick ascending limb and cortical collecting duct in ROMK (Bartter's) knockout mice (2002). https://pmc.ncbi.nlm.nih.gov/articles/PMC4426997/ DOI: 10.1074/jbc.M206644200
    tissue_or_cell_type
    Thick ascending limb
    trigger_kind
    machinery_impairment Imported condition classification; unverified.

    Potassium: cross-nutrient mechanisms and deficiency (2026-09-17) · lines 561–573

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Pan-Romk deletion; micropuncture and companion patch-clamp studies · source_derived_draft · unverified_draft

    ### renal-romk-supports-tal-salt-reabsorption Romk-null mice had reduced, but persisting, TAL NaCl absorption by micropuncture; the companion study demonstrated loss of native apical small-conductance K channels. Condition category: machinery_impairment nutrient_topic: Potassium research collection; topical membership is not evidence of a direct dietary effect. plain_language: ROMK-mediated potassium recycling supports loop salt recovery, while residual salt transport survives its deletion. organism: Mus musculus tissue_or_cell_type: Thick ascending limb experimental_model: Pan-Romk deletion; micropuncture and companion patch-clamp studies limitations: Hydronephrosis, developmental disease and compensatory transport complicate whole-kidney endpoints. cross_nutrient: Loss of potassium-channel machinery impairs sodium/chloride recovery. evidence_location: Lorenz primary abstract: micropuncture; Lu Results: TAL patch-clamp. [lorenz-2002-romk-tal] Impaired renal NaCl absorption in mice lacking the ROMK potassium channel, a model for type II Bartter's syndrome (2002). https://pubmed.ncbi.nlm.nih.gov/12122007/ DOI: 10.1074/jbc.M205627200 [lu-2002-romk-null] Absence of small conductance K+ channel (SK) activity in apical membranes of thick ascending limb and cortical collecting duct in ROMK (Bartter's) knockout mice (2002). https://pmc.ncbi.nlm.nih.gov/articles/PMC4426997/ DOI: 10.1074/jbc.M206644200
    Complete structured claim and evidence

What acts on it

  1. Combined Na/Mg restriction increased native ROMK activity in DCT2/CNT and lowered plasma K, while ENaC cleavage markers were preserved relative to normal diet.

    Magnesium → Renal outer medullary potassium channel / KCNJ1 source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    nutrient_deficiency Imported condition classification; unverified.
    cross_nutrient
    magnesium -> sodium -> potassium
    duration
    Seven days
    experimental_contrast
    {"combination": "joint", "comparator": "Normal diet", "conditions": [{"entity_slug": "sodium", "state": "Restricted"}, {"entity_slug": "magnesium", "state": "Restricted"}], "effect_direction": "increase", "endpoint": "Native ROMK activity in DCT2/CNT", "intervention": "Combined dietary sodium and magnesium restriction"} Primary abstract PMID 41137719 / DOI 10.1113/JP287704 rechecked 2026-09-20. This comparison must not be separated into two single-deficiency effects.
    experimental_model
    Dietary restriction in C57BL/6J mice with renal transport assays
    limitations
    Co-occurrence supports the proposed mechanism; intracellular Mg and distal Na delivery were not directly measured.
    nutrient_topic
    Magnesium research collection; topical membership is not evidence of a direct dietary effect. · Magnesium
    organism
    Mus musculus
    plain_language
    In this combined shortage, the Mg-sensitive potassium pathway was more active while the sodium pathway that supports potassium exit remained available.
    primary_references
    [maeoka-2025-enac-romk] Hypomagnesaemia-associated hypokalaemia requires activation of both ENaC and ROMK (2025). https://pubmed.ncbi.nlm.nih.gov/41137719/ DOI: 10.1113/JP287704
    tissue_or_cell_type
    Kidney distal nephron
    trigger_kind
    nutrient_deficiency Imported condition classification; unverified.

    Magnesium: cross-nutrient mechanisms and deficiency (2026-09-17) · lines 178–189

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Dietary restriction in C57BL/6J mice with renal transport assays · source_derived_draft · unverified_draft

    ### combined-na-mg-restriction-romk-hypokalemia Combined Na/Mg restriction increased native ROMK activity in DCT2/CNT and lowered plasma K, while ENaC cleavage markers were preserved relative to normal diet. Condition category: nutrient_deficiency nutrient_topic: Magnesium research collection; topical membership is not evidence of a direct dietary effect. plain_language: In this combined shortage, the Mg-sensitive potassium pathway was more active while the sodium pathway that supports potassium exit remained available. organism: Mus musculus tissue_or_cell_type: Kidney distal nephron experimental_model: Dietary restriction in C57BL/6J mice with renal transport assays limitations: Co-occurrence supports the proposed mechanism; intracellular Mg and distal Na delivery were not directly measured. cross_nutrient: magnesium -> sodium -> potassium duration: Seven days [maeoka-2025-enac-romk] Hypomagnesaemia-associated hypokalaemia requires activation of both ENaC and ROMK (2025). https://pubmed.ncbi.nlm.nih.gov/41137719/ DOI: 10.1113/JP287704
    Complete structured claim and evidence

  2. Mg2+ supplied through the whole-cell pipette reduced tertiapin-Q-sensitive current in rat cortical collecting-duct principal cells.

    Mg2+ → Renal outer medullary potassium channel / KCNJ1 source_derived_draftungraded
    Experimental context and source evidence
    cross_nutrient
    magnesium -> potassium
    experimental_model
    Whole-cell patch-clamp with controlled pipette Mg
    limitations
    Pipette-controlled Mg and voltage are not measurements of intracellular Mg during a human deficiency.
    nutrient_topic
    Magnesium research collection; topical membership is not evidence of a direct dietary effect. · Magnesium
    organism
    Rattus norvegicus
    plain_language
    Native kidney-cell recordings support the Mg brake on ROMK potassium flow seen in expressed channels.
    primary_references
    [yang-2010-romk-magnesium] Magnesium modulates ROMK channel-mediated potassium secretion (2010). https://pubmed.ncbi.nlm.nih.gov/21030597/ DOI: 10.1681/ASN.2010060617
    tissue_or_cell_type
    Cortical collecting-duct principal cells

    Magnesium: cross-nutrient mechanisms and deficiency (2026-09-17) · lines 129–139

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Whole-cell patch-clamp with controlled pipette Mg · source_derived_draft · unverified_draft

    ### mg-native-ccd-romk-current-block Mg2+ supplied through the whole-cell pipette reduced tertiapin-Q-sensitive current in rat cortical collecting-duct principal cells. Condition category: normal nutrient_topic: Magnesium research collection; topical membership is not evidence of a direct dietary effect. plain_language: Native kidney-cell recordings support the Mg brake on ROMK potassium flow seen in expressed channels. organism: Rattus norvegicus tissue_or_cell_type: Cortical collecting-duct principal cells experimental_model: Whole-cell patch-clamp with controlled pipette Mg limitations: Pipette-controlled Mg and voltage are not measurements of intracellular Mg during a human deficiency. cross_nutrient: magnesium -> potassium [yang-2010-romk-magnesium] Magnesium modulates ROMK channel-mediated potassium secretion (2010). https://pubmed.ncbi.nlm.nih.gov/21030597/ DOI: 10.1681/ASN.2010060617
    Complete structured claim and evidence

Where it participates (unsigned role)

  1. The mouse findings support a model in which sustained ENaC sodium entry and higher ROMK conductance jointly favor potassium secretion during combined Na/Mg restriction.

    Epithelial sodium channel → Distal renal potassium secretion source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    nutrient_deficiency Imported condition classification; unverified.
    cross_nutrient
    magnesium -> sodium -> potassium
    experimental_model
    Dietary restriction in C57BL/6J mice with renal transport assays
    limitations
    Integrated mechanism supported across experiments; enhanced distal Na delivery was not demonstrated and is not required by these data.
    nutrient_topic
    Magnesium research collection; topical membership is not evidence of a direct dietary effect. · Magnesium
    organism
    Mus musculus
    plain_language
    Sodium entry changes the electrical conditions for potassium exit; lifting the Mg brake on ROMK matters when that driving force is available.
    primary_references
    [maeoka-2025-enac-romk] Hypomagnesaemia-associated hypokalaemia requires activation of both ENaC and ROMK (2025). https://pubmed.ncbi.nlm.nih.gov/41137719/ DOI: 10.1113/JP287704 [yang-2010-romk-magnesium] Magnesium modulates ROMK channel-mediated potassium secretion (2010). https://pubmed.ncbi.nlm.nih.gov/21030597/ DOI: 10.1681/ASN.2010060617
    spatial_transport_direction
    Na+: tubular lumen to cell via ENaC; K+: cell to lumen via ROMK.
    tissue_or_cell_type
    Kidney distal nephron
    trigger_kind
    nutrient_deficiency Imported condition classification; unverified.

    Magnesium: cross-nutrient mechanisms and deficiency (2026-09-17) · lines 203–215

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Dietary restriction in C57BL/6J mice with renal transport assays · source_derived_draft · unverified_draft

    ### mg-romk-enac-conditional-k-secretory-chain The mouse findings support a model in which sustained ENaC sodium entry and higher ROMK conductance jointly favor potassium secretion during combined Na/Mg restriction. Condition category: nutrient_deficiency nutrient_topic: Magnesium research collection; topical membership is not evidence of a direct dietary effect. plain_language: Sodium entry changes the electrical conditions for potassium exit; lifting the Mg brake on ROMK matters when that driving force is available. organism: Mus musculus tissue_or_cell_type: Kidney distal nephron experimental_model: Dietary restriction in C57BL/6J mice with renal transport assays limitations: Integrated mechanism supported across experiments; enhanced distal Na delivery was not demonstrated and is not required by these data. cross_nutrient: magnesium -> sodium -> potassium spatial_transport_direction: Na+: tubular lumen to cell via ENaC; K+: cell to lumen via ROMK. [maeoka-2025-enac-romk] Hypomagnesaemia-associated hypokalaemia requires activation of both ENaC and ROMK (2025). https://pubmed.ncbi.nlm.nih.gov/41137719/ DOI: 10.1113/JP287704 [yang-2010-romk-magnesium] Magnesium modulates ROMK channel-mediated potassium secretion (2010). https://pubmed.ncbi.nlm.nih.gov/21030597/ DOI: 10.1681/ASN.2010060617
    Complete structured claim and evidence

  2. ARH bound the ROMK internalization motif and promoted endocytosis in COS-7 cells; Arh deletion altered dietary regulation of renal ROMK.

    Low-density lipoprotein receptor adaptor protein 1 → ROMK endocytosis source_derived_draftungraded
    Experimental context and source evidence
    evidence_location
    Abstract; binding motif experiments and renal Arh-null comparison.
    experimental_model
    Binding, knockdown and Arh-null dietary experiments
    limitations
    Cell uptake mechanism and mouse dietary phenotype are complementary experiments.
    nutrient_topic
    Potassium research collection; topical membership is not evidence of a direct dietary effect. · Potassium
    organism
    Chlorocebus-derived COS-7 cells; Mus musculus
    plain_language
    An adaptor helps pull ROMK from the membrane and contributes to potassium-dependent channel adjustment.
    primary_references
    [fang-2009-arh-romk] The ARH adaptor protein regulates endocytosis of the ROMK potassium secretory channel in mouse kidney (2009). https://pmc.ncbi.nlm.nih.gov/articles/PMC2769171/ DOI: 10.1172/JCI37950
    tissue_or_cell_type
    Cell system and distal nephron

    Potassium: cross-nutrient mechanisms and deficiency (2026-09-17) · lines 332–342

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

    ### renal-arh-targets-romk-endocytosis ARH bound the ROMK internalization motif and promoted endocytosis in COS-7 cells; Arh deletion altered dietary regulation of renal ROMK. Condition category: normal nutrient_topic: Potassium research collection; topical membership is not evidence of a direct dietary effect. plain_language: An adaptor helps pull ROMK from the membrane and contributes to potassium-dependent channel adjustment. organism: Chlorocebus-derived COS-7 cells; Mus musculus tissue_or_cell_type: Cell system and distal nephron experimental_model: Binding, knockdown and Arh-null dietary experiments limitations: Cell uptake mechanism and mouse dietary phenotype are complementary experiments. evidence_location: Abstract; binding motif experiments and renal Arh-null comparison. [fang-2009-arh-romk] The ARH adaptor protein regulates endocytosis of the ROMK potassium secretory channel in mouse kidney (2009). https://pmc.ncbi.nlm.nih.gov/articles/PMC2769171/ DOI: 10.1172/JCI37950
    Complete structured claim and evidence

  3. After 48 hours of dietary K deficiency, rat CCD ROMK shifted from apical membrane toward endosomal/lysosomal locations.

    Potassium → ROMK endocytosis source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    nutrient_deficiency Imported condition classification; unverified.
    evidence_location
    Abstract; early/late endosomal marker colocalization.
    experimental_model
    Dietary restriction; confocal localization
    limitations
    Localization supports internalization/degradation; microscopy does not directly measure secretion.
    nutrient_topic
    Potassium research collection; topical membership is not evidence of a direct dietary effect. · Potassium
    organism
    Rattus norvegicus
    plain_language
    The kidney removes potassium exit channels from the surface when potassium is scarce.
    primary_references
    [chu-2003-romk-endocytosis] Dietary potassium restriction stimulates endocytosis of ROMK channel in rat cortical collecting duct (2003). https://journals.physiology.org/doi/10.1152/ajprenal.00150.2003 DOI: 10.1152/ajprenal.00150.2003
    tissue_or_cell_type
    Cortical collecting duct
    trigger_kind
    nutrient_deficiency Imported condition classification; unverified.

    Potassium: cross-nutrient mechanisms and deficiency (2026-09-17) · lines 320–330

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Dietary restriction; confocal localization · source_derived_draft · unverified_draft

    ### renal-low-k-romk-internalization After 48 hours of dietary K deficiency, rat CCD ROMK shifted from apical membrane toward endosomal/lysosomal locations. Condition category: nutrient_deficiency nutrient_topic: Potassium research collection; topical membership is not evidence of a direct dietary effect. plain_language: The kidney removes potassium exit channels from the surface when potassium is scarce. organism: Rattus norvegicus tissue_or_cell_type: Cortical collecting duct experimental_model: Dietary restriction; confocal localization limitations: Localization supports internalization/degradation; microscopy does not directly measure secretion. evidence_location: Abstract; early/late endosomal marker colocalization. [chu-2003-romk-endocytosis] Dietary potassium restriction stimulates endocytosis of ROMK channel in rat cortical collecting duct (2003). https://journals.physiology.org/doi/10.1152/ajprenal.00150.2003 DOI: 10.1152/ajprenal.00150.2003
    Complete structured claim and evidence

  4. Romk1-specific deletion blunted high-K-induced collecting-tubule ROMK surface recruitment and caused hyperkalemia during that challenge.

    ROMK1 splice isoform → Apical ROMK channel abundance source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    machinery_impairment Imported condition classification; unverified.
    evidence_location
    Abstract; high-K channel-number and localization comparison.
    experimental_model
    Isoform-specific knockout; high-K diet
    limitations
    Baseline channel gating and NKCC2 phenotype were preserved; not equivalent to pan-ROMK deletion.
    nutrient_topic
    Potassium research collection; topical membership is not evidence of a direct dietary effect. · Potassium
    organism
    Mus musculus
    plain_language
    This ROMK splice isoform helps increase potassium exit-channel availability when intake rises.
    primary_references
    [romk1-2016-isoform] Romk1 Knockout Mice Do Not Produce Bartter Phenotype but Exhibit Impaired K Excretion (2016). https://pmc.ncbi.nlm.nih.gov/articles/PMC4777858/ DOI: 10.1074/jbc.M115.707877
    tissue_or_cell_type
    Collecting tubule
    trigger_kind
    machinery_impairment Imported condition classification; unverified.

    Potassium: cross-nutrient mechanisms and deficiency (2026-09-17) · lines 344–354

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Isoform-specific knockout; high-K diet · source_derived_draft · unverified_draft

    ### renal-romk1-needed-high-k-adaptation Romk1-specific deletion blunted high-K-induced collecting-tubule ROMK surface recruitment and caused hyperkalemia during that challenge. Condition category: machinery_impairment nutrient_topic: Potassium research collection; topical membership is not evidence of a direct dietary effect. plain_language: This ROMK splice isoform helps increase potassium exit-channel availability when intake rises. organism: Mus musculus tissue_or_cell_type: Collecting tubule experimental_model: Isoform-specific knockout; high-K diet limitations: Baseline channel gating and NKCC2 phenotype were preserved; not equivalent to pan-ROMK deletion. evidence_location: Abstract; high-K channel-number and localization comparison. [romk1-2016-isoform] Romk1 Knockout Mice Do Not Produce Bartter Phenotype but Exhibit Impaired K Excretion (2016). https://pmc.ncbi.nlm.nih.gov/articles/PMC4777858/ DOI: 10.1074/jbc.M115.707877
    Complete structured claim and evidence

  5. Renal Sgk1 deletion blunted the early increase in urinary K excretion on high-K feeding, with hyperkalemia and reduced ENaC processing.

    Serum and glucocorticoid-regulated kinase 1 → Urinary potassium excretion source_derived_draftungraded
    Experimental context and source evidence
    availability_state
    machinery_impairment Imported condition classification; unverified.
    cross_nutrient
    Impaired ENaC sodium-channel adaptation accompanies defective K clearance.
    evidence_location
    Results Figure 2; two-day versus five-day dietary comparison.
    experimental_model
    Inducible tubular deletion; two-day high-K citrate diet
    limitations
    Excretion approached controls after longer adaptation; ROMK apical localization increased rather than decreased.
    nutrient_topic
    Potassium research collection; topical membership is not evidence of a direct dietary effect. · Potassium
    organism
    Mus musculus
    plain_language
    Removing kidney SGK1 impairs the initial ability to clear a potassium load.
    primary_references
    [al-qusairi-2016-renal-sgk1] Renal tubular SGK1 deficiency causes impaired K+ excretion via loss of regulation of NEDD4-2/WNK1 and ENaC (2016). https://pmc.ncbi.nlm.nih.gov/articles/PMC5005279/ DOI: 10.1152/ajprenal.00002.2016
    tissue_or_cell_type
    Kidney tubules
    trigger_kind
    machinery_impairment Imported condition classification; unverified.

    Potassium: cross-nutrient mechanisms and deficiency (2026-09-17) · lines 434–445

    AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Inducible tubular deletion; two-day high-K citrate diet · source_derived_draft · unverified_draft

    ### renal-sgk1-loss-impairs-high-k-excretion Renal Sgk1 deletion blunted the early increase in urinary K excretion on high-K feeding, with hyperkalemia and reduced ENaC processing. Condition category: machinery_impairment nutrient_topic: Potassium research collection; topical membership is not evidence of a direct dietary effect. plain_language: Removing kidney SGK1 impairs the initial ability to clear a potassium load. organism: Mus musculus tissue_or_cell_type: Kidney tubules experimental_model: Inducible tubular deletion; two-day high-K citrate diet limitations: Excretion approached controls after longer adaptation; ROMK apical localization increased rather than decreased. cross_nutrient: Impaired ENaC sodium-channel adaptation accompanies defective K clearance. evidence_location: Results Figure 2; two-day versus five-day dietary comparison. [al-qusairi-2016-renal-sgk1] Renal tubular SGK1 deficiency causes impaired K+ excretion via loss of regulation of NEDD4-2/WNK1 and ENaC (2016). https://pmc.ncbi.nlm.nih.gov/articles/PMC5005279/ DOI: 10.1152/ajprenal.00002.2016
    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