Pathway candidateNCBI-verifiedprotein-coding

SLC22A4

solute carrier family 22 member 4

NCBI Gene: 6583 Ensembl GeneCards UniProt: Q9H015

Pathway candidate — not linked to PFS or PSSD by any record here

SLC22A4 is in the library because it belongs to the drug transporters family. No study, report or commentary in the corpus names it, so a variant in SLC22A4 is not, by itself, evidence of anything related to post-drug syndromes.

Gene summary

A protein-coding gene on chromosome 5 (drug and xenobiotic transporters). Polyspecific organic cation transporters in the liver, kidney, intestine, and other organs are critical for elimination of many endogenous small organic cations as well as a wide array of drugs and environmental toxins. The protein is an organic cation transporter and plasma integral membrane protein containing eleven putative transmembrane domains as well as a nucleotide-binding site motif.

Source: NCBI Gene, accessed 2026-10-07.

Protein reference (UniProt)

Protein: Solute carrier family 22 member 4
Function (excerpt): Transporter that mediates the transport of endogenous and microbial zwitterions and organic cations. Functions as a Na(+)-dependent and pH-dependent high affinity microbial symporter of potent food-derived antioxidant ergothioeine. Transports one sodium ion with one ergothioeine molecule (By similarity). Involved in the absorption of ergothioneine from the luminal/apical side of the small intestine and renal tubular cells, and into non-parenchymal liver cells, thereby contributing to maintain steady-state ergothioneine level in the body. Also mediates the bidirectional transport of acetycholine, although the exact transport mechanism has not been fully identified yet. Most likely exports anti-inflammatory acetylcholine in non-neuronal tissues, thereby contributing to the non-neuronal cholinergic system. Displays a general physiological role linked to better survival by controlling inflammation and oxidative stress, which may be related to ergothioneine and acetycholine transports.
Subcellular location: Apical cell membrane; Basal cell membrane; Mitochondrion membrane.
Tissue specificity: Widely expressed. Highly expressed in kidney, trachea, ileum, bone marrow and whole blood. Expressed in small intestines. Weakly expressed in skeletal muscle, prostate, lung, pancreas, placenta, heart, uterus, spleen and spinal cord. Expressed in testis, primarily to the basal membrane of Sertoli cells. Expressed in brain. Expressed in liver. Highly expressed in intestinal cell types affected by Crohn disease, including epithelial cells. Expressed in CD68 macrophage and CD43 T-cells but not in CD20 B-cells. Predominantly expressed in CD14 cells in peripheral blood mononuclear cells. Expressed in fetal liver, kidney and lung.
Associated conditions: Rheumatoid arthritis (RA).

Source: UniProtKB/Swiss-Prot Q9H015, release 2026_03, licensed CC BY 4.0. This is the protein’s normal biology, not evidence about post-drug syndromes; associated conditions are inherited disorders of the gene, not PFS, PSSD or PRSD.

Why its pathway is in the library

Transporters set systemic exposure to finasteride/SSRIs and clear conjugated steroid metabolites — directly relevant to both drug pharmacokinetics and Powers' clearance-centered PFS mechanism.

Written for the whole drug transporters family, not for SLC22A4 specifically.

Mentioned in 0 corpus records

No corpus record names SLC22A4 directly yet. It is in the library because it sits in a pathway the corpus tracks (Drug transporters).

Also in drug and xenobiotic transporters

All 62 genes

Browse by family on the gene families page.

Gene summary

Source: NCBI Gene, accessed 2026-10-07.

Protein reference (UniProt)

Protein: Solute carrier family 22 member 4
Function (excerpt): Transporter that mediates the transport of endogenous and microbial zwitterions and organic cations. Functions as a Na(+)-dependent and pH-dependent high affinity microbial symporter of potent food-derived antioxidant ergothioeine. Transports one sodium ion with one ergothioeine molecule (By similarity). Involved in the absorption of ergothioneine from the luminal/apical side of the small intestine and renal tubular cells, and into non-parenchymal liver cells, thereby contributing to maintain steady-state ergothioneine level in the body. Also mediates the bidirectional transport of acetycholine, although the exact transport mechanism has not been fully identified yet. Most likely exports anti-inflammatory acetylcholine in non-neuronal tissues, thereby contributing to the non-neuronal cholinergic system. Displays a general physiological role linked to better survival by controlling inflammation and oxidative stress, which may be related to ergothioneine and acetycholine transports.
Subcellular location: Apical cell membrane; Basal cell membrane; Mitochondrion membrane.
Tissue specificity: Widely expressed. Highly expressed in kidney, trachea, ileum, bone marrow and whole blood. Expressed in small intestines. Weakly expressed in skeletal muscle, prostate, lung, pancreas, placenta, heart, uterus, spleen and spinal cord. Expressed in testis, primarily to the basal membrane of Sertoli cells. Expressed in brain. Expressed in liver. Highly expressed in intestinal cell types affected by Crohn disease, including epithelial cells. Expressed in CD68 macrophage and CD43 T-cells but not in CD20 B-cells. Predominantly expressed in CD14 cells in peripheral blood mononuclear cells. Expressed in fetal liver, kidney and lung.
Associated conditions: Rheumatoid arthritis (RA).