RRM2B

RRM2B is the small subunit of a p53-inducible ribonucleotide reductase. This heterotetrameric enzyme catalyzes the conversion of ribonucleoside diphosphates to deoxyribonucleoside diphosphates. The product of this reaction is necessary for DNA synthesis. Mutations in this gene have been associated with autosomal recessive mitochondrial DNA depletion syndrome, autosomal dominant progressive external ophthalmoplegia-5, and mitochondrial neurogastrointestinal encephalopathy. Alternatively spliced transcript variants have been described.

Full Name

Ribonucleotide Reductase Regulatory TP53 Inducible Subunit M2B

Function

Plays a pivotal role in cell survival by repairing damaged DNA in a p53/TP53-dependent manner. Supplies deoxyribonucleotides for DNA repair in cells arrested at G1 or G2. Contains an iron-tyrosyl free radical center required for catalysis. Forms an active ribonucleotide reductase (RNR) complex with RRM1 which is expressed both in resting and proliferating cells in response to DNA damage.

Biological Process

Biological Process 2'-deoxyribonucleotide biosynthetic processManual Assertion Based On ExperimentIDA:ComplexPortal
Biological Process deoxyribonucleoside triphosphate metabolic processIEA:Ensembl
Biological Process deoxyribonucleotide biosynthetic processManual Assertion Based On ExperimentIBA:GO_Central
Biological Process DNA repairManual Assertion Based On ExperimentIDA:ComplexPortal
Biological Process DNA synthesis involved in DNA repair1 PublicationIC:ComplexPortal
Biological Process kidney developmentIEA:Ensembl
Biological Process mitochondrial DNA replicationManual Assertion Based On ExperimentIMP:ComplexPortal
Biological Process negative regulation of intrinsic apoptotic signaling pathway by p53 class mediatorIEA:Ensembl
Biological Process positive regulation of G0 to G1 transitionManual Assertion Based On ExperimentIDA:ComplexPortal
Biological Process positive regulation of G2/M transition of mitotic cell cycleManual Assertion Based On ExperimentIDA:ComplexPortal
Biological Process renal system processIEA:Ensembl
Biological Process response to amineIEA:Ensembl
Biological Process response to oxidative stressIEA:Ensembl
Biological Process ribonucleoside diphosphate metabolic processManual Assertion Based On ExperimentIDA:ComplexPortal

Cellular Location

Cytoplasm
Nucleus
Translocates from cytoplasm to nucleus in response to DNA damage.

Involvement in disease

Mitochondrial DNA depletion syndrome 8A (MTDPS8A):
A disorder due to mitochondrial dysfunction characterized by various combinations of neonatal hypotonia, neurological deterioration, respiratory distress, lactic acidosis, and renal tubulopathy.
Mitochondrial DNA depletion syndrome 8B (MTDPS8B):
A disease due to mitochondrial dysfunction and characterized by ophthalmoplegia, ptosis, gastrointestinal dysmotility, cachexia, peripheral neuropathy.
Progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal dominant, 5 (PEOA5):
A disorder characterized by progressive weakness of ocular muscles and levator muscle of the upper eyelid. In a minority of cases, it is associated with skeletal myopathy, which predominantly involves axial or proximal muscles and which causes abnormal fatigability and even permanent muscle weakness. Ragged-red fibers and atrophy are found on muscle biopsy. A large proportion of chronic ophthalmoplegias are associated with other symptoms, leading to a multisystemic pattern of this disease. Additional symptoms are variable, and may include cataracts, hearing loss, sensory axonal neuropathy, ataxia, depression, hypogonadism, and parkinsonism.