PNPT1

Chr 2p16.1

polyribonucleotide nucleotidyltransferase 1

Aliases:: PNPase, OLD35, old-35
MANE:: ENST00000447944.7

OMIM: 610316 ↗NCBI: 87178 ↗Ensembl ↗

Annotations refreshed 1 month ago.

Predicted protein structure

AlphaFold predicted structure

PNPT1 · Q8TCS8

v62025-08-01

Predicted Aligned Error matrix for PNPT1 — diagonal shows residue index, colour shows pairwise prediction confidence (lower is better) — Predicted Aligned Error

Mean pLDDT

87.4/ 100

Confident

783 residues

Confidence breakdown

Very high(≥ 90)71%
Confident(70–90)17%
Low(50–70)3%
Very low(< 50)9%

Open interactive 3D viewer

AlphaFold (Jumper et al., 2021) · CC BY 4.0

Clinical relevance (Genomics England PanelApp)

Diagnostic Grade (Green)

Ataxia and cerebellar anomalies - narrow panel
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted
Childhood onset dystonia, chorea or related movement disorder
BIALLELIC, autosomal or pseudoautosomal
DDG2P
BIALLELIC, autosomal or pseudoautosomal
Early onset or syndromic epilepsy
BIALLELIC, autosomal or pseudoautosomal
Hereditary neuropathy or pain disorder
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted
Intellectual disability
BIALLELIC, autosomal or pseudoautosomal
Likely inborn error of metabolism
BIALLELIC, autosomal or pseudoautosomal
Mitochondrial disorders
BIALLELIC, autosomal or pseudoautosomal

+9 more panels — install the extension to see the full list inline on any page.

Disease associations (Open Targets)

combined oxidative phosphorylation defect type 13
0.81
autosomal recessive nonsyndromic hearing loss 70
0.74
spinocerebellar ataxia type 25
0.70
deafness
0.68
hearing loss, autosomal recessive
0.63
hereditary disease
0.51
hearing loss disorder
0.46
open-angle glaucoma
0.44
hypothyroidism
0.41
glaucoma
0.41

Score is the Open Targets composite evidence score (0-1). Higher = stronger gene-disease association.

Protein function (UniProt)

Polyribonucleotide nucleotidyltransferase 1, mitochondrial

RNA-binding protein implicated in numerous RNA metabolic processes (PubMed:29967381, PubMed:39019044). Catalyzes the phosphorolysis of single-stranded polyribonucleotides processively in the 3'-to-5' direction (PubMed:29967381, PubMed:39019044). Mitochondrial intermembrane factor with RNA-processing exoribonulease activity (PubMed:29967381, PubMed:39019044). Component of the mitochondrial degradosome (mtEXO) complex, that degrades 3' overhang double-stranded RNA with a 3'-to-5' directionality in an ATP-dependent manner (PubMed:29967381, PubMed:39019044). Involved in the degradation of non-coding mitochondrial transcripts (MT-ncRNA) and tRNA-like molecules (PubMed:29967381, PubMed:39019044). Required for correct processing and polyadenylation of mitochondrial mRNAs. Plays a role as a cytoplasmic RNA import factor that mediates the translocation of small RNA components, like the 5S RNA, the RNA subunit of ribonuclease P and the mitochondrial RNA-processing (MRP) RNA, into the mitochondrial matrix. Plays a role in mitochondrial morphogenesis and respiration; regulates the expression of the electron transport chain (ETC) components at the mRNA and protein levels. In the cytoplasm, shows a 3'-to-5' exoribonuclease mediating mRNA degradation activity; degrades c-myc mRNA upon treatment with IFNB1/IFN-beta, resulting in a growth arrest in melanoma cells. Regulates the stability of specific mature miRNAs in melanoma cells; specifically and selectively degrades miR-221, preferentially. Also plays a role in RNA cell surveillance by cleaning up oxidized RNAs. Binds to the RNA subunit of ribonuclease P, MRP RNA and miR-221 microRNA