TIMM21

Chr 18

translocase of inner mitochondrial membrane 21

Also known as: C18orf55, HSPC154, TIM21

NCBI Gene: 29090 ENSG00000075336 UniProt: Q9BVV7 OMIM: 615180

The TIMM21 protein facilitates translocation of nuclear-encoded proteins across the mitochondrial inner membrane and is required for assembly of respiratory chain complexes I and IV as part of the MITRAC complex. Mutations cause autosomal recessive mitochondrial complex I deficiency with associated neurodegeneration, developmental delay, and multi-organ involvement. The gene shows relatively low constraint against loss-of-function variants.

OMIM ResearchSummary from RefSeq, UniProt

Involved in mitochondrial respiratory chain complex I assembly; mitochondrial respiratory chain complex IV assembly; and protein import into mitochondrial matrix. Located in mitochondrion. Part of TIM23 mitochondrial import inner membrane translocase complex. [provided by Alliance of Genome Resources, Jun 2026]

OMIM ResearchGenerating clinical summary…

Active trials

Pubs (1 yr)

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P/LP submissions

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P/LP missense

1.15

LOEUF

Mechanism· predicted