POLM
Description
The POLM (DNA polymerase mu) is a protein-coding gene located on chromosome 7.
Pol μ is a DNA polymerase enzyme found in eukaryotes. In humans, it is encoded by the POLM gene. Pol μ is a member of the X family of DNA polymerases and participates in the resynthesis of damaged or missing nucleotides during the non-homologous end joining (NHEJ) pathway of DNA repair. It interacts with Ku and DNA ligase IV, which are also involved in NHEJ. Pol μ is structurally and functionally related to pol λ and, like pol λ, has a BRCT domain that is thought to mediate interactions with other DNA repair proteins. Unlike pol λ, however, pol μ can add a base to a blunt end that is templated by the overhang on the opposite end of the double-strand break. Pol μ is also closely related to terminal deoxynucleotidyl transferase (TdT), a specialized DNA polymerase that adds random nucleotides to DNA ends during V(D)J recombination, the process by which B-cell and T-cell receptor diversity is generated in the vertebrate immune system. Like TdT, pol μ participates in V(D)J recombination, but only during light chain rearrangements. This is distinct from pol λ, which is involved in heavy chain rearrangements. In polymerase mu mutant mice, hematopoietic cell development is defective in several peripheral and bone marrow cell populations with about a 40% decrease in bone marrow cell number that includes several hematopoietic lineages.
POLM is also known as Pol Mu, Tdt-N.
Associated Diseases
- ovarian cancer
- esophageal cancer
- neutropenia, severe congenital, 2, autosomal dominant
- Okt4 epitope deficiency
- combined immunodeficiency with skin granulomas
- common variable immunodeficiency
- immunodeficiency 18
- hyper-IgM syndrome type 3
- immunodeficiency 99 with hypogammaglobulinemia and autoimmune cytopenias
- immunodeficiency 105
- reticular dysgenesis
- BENTA disease
- immunodeficiency 73c with defective neutrophil chemotaxis and hypogammaglobulinemia
- severe combined immunodeficiency due to CTPS1 deficiency
