POLRMT
Function
DNA-dependent RNA polymerase catalyzes the transcription of mitochondrial DNA into RNA using the four ribonucleoside triphosphates as substrates (PubMed:21278163, PubMed:33602924). Component of the mitochondrial transcription initiation complex, composed at least of TFB2M, TFAM and POLRMT that is required for basal transcription of mitochondrial DNA (PubMed:29149603). In this complex, TFAM recruits POLRMT to a specific promoter whereas TFB2M induces structural changes in POLRMT to enable promoter opening and trapping of the DNA non-template strand (PubMed:29149603). Has DNA primase activity (PubMed:18685103, PubMed:33602924). Catalyzes the synthesis of short RNA primers that are necessary for the initiation of lagging-strand DNA synthesis from the origin of light-strand DNA replication (OriL) (PubMed:18685103, PubMed:33602924).
Involvement in disease
Combined oxidative phosphorylation deficiency 55
COXPD55
A mitochondrial disease characterized by global developmental delay, hypotonia, short stature, and impaired intellectual development with speech disabilities in childhood. Indolent progressive external ophthalmoplegia may be present in some patients. COXPD55 transmission pattern is consistent with autosomal dominant inheritance in some families, and with autosomal recessive inheritance in others.
None
The disease is caused by variants affecting the gene represented in this entry.
Sequence Similarities
Belongs to the phage and mitochondrial RNA polymerase family.
Cellular localization
- Mitochondrion
Alternative names
MtRPOL, POLRMT