DNA polymerase iota is anenzyme that in humans is encoded by thePOLIgene.[4] It is found in higher eukaryotes, and is believed to have arisen from a gene duplication fromPol η. Pol ι, is aY family polymerase that is involved intranslesion synthesis. It can bypass 6-4 pyrimidine adducts and abasic sites and has a high frequency of wrong base incorporation. Like many other Y family polymerases Pol ι, has low processivity, a large DNA binding pocket and doesn't undergo conformational changes when DNA binds. These attributes are what allow Pol ι to carry out its task as a translesion polymerase. Pol ι only usesHoogsteen base pairing, during DNA synthesis, it will addadenine opposite tothymine in the syn conformation and can add bothcytosine and thymine in the anti conformation acrossguanine, which it flips to the syn conformation.
Xeroderma pigmentosum variant (XPV) cells lackDNA polymerase eta (η).[5] Instead these cells use DNA polymerase iota (ι).[5] Exposure of XPV cells to UV light causes a very high frequency and unique spectrum of UV-induced mutations that can ultimately lead to malignant transformation.[5]
PDB gallery | |
|---|---|
|
 | This article on agene on humanchromosome 18 is astub. You can help Wikipedia byexpanding it. |
