TSPO
translocator protein
Gene summary
A protein-coding gene on chromosome 22 (steroid hormone synthesis, neurotransmission). Present mainly in the mitochondrial compartment of peripheral tissues, the protein encoded by this gene interacts with some benzodiazepines and has different affinities than its endogenous counterpart. The protein is a key factor in the flow of cholesterol into mitochondria to permit the initiation of steroid hormone synthesis.
Source: NCBI Gene, accessed 2026-10-07.
Protein reference (UniProt)
- Protein
Translocator protein
- Function
Can bind protoporphyrin IX and may play a role in the transport of porphyrins and heme (By similarity). Promotes the transport of cholesterol across mitochondrial membranes and may play a role in lipid metabolism, but its precise physiological role is controversial. It is apparently not required for steroid hormone biosynthesis. Was initially identified as peripheral-type benzodiazepine receptor; can also bind isoquinoline carboxamides.
- Subcellular location
Mitochondrion membrane.
- Tissue specificity
Found in many tissue types. Expressed at the highest levels under normal conditions in tissues that synthesize steroids.
Source: UniProtKB/Swiss-Prot P30536, 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
Steroid-synthesis enzymes sit directly on the pathways perturbed by 5-alpha-reductase inhibitors and SSRIs; inherited variation here is a candidate susceptibility factor for persistent post-drug phenotypes. Monoamine, GABA, glutamate, and cholinergic systems are the direct pharmacologic targets of SSRIs/SNRIs (PSSD) and the downstream effectors of neurosteroid signaling (PFS).
Written for the whole steroid synthesis / neurotransmission family, not for TSPO specifically.
Mentioned in 1 corpus record
- Conference abstractPSSD Discord pick
(166) Paroxetine-induced alterations in neurosteroidogenic gene expression in the female nucleus accumbens: insights into post-SSRI sexual dysfunction
G Chrostek, S Diviccaro, L Cioffi, R C Melcangi, S Giatti · The Journal of Sexual Medicine
Congress abstract (J Sex Med Vol 23, Suppl 4, June 2026; article page 403'd, metadata recovered via Crossref) reporting paroxetine effects on neurosteroid-synthesis genes in female rats, a neglected sex in PSSD research. qPCR of the nucleus accumbens after 14…
STARTSPODISC-0162026PFSPSSDPSSD Discord picks
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