Structural highlights
Function
DPOLQ_HUMAN Has a DNA polymerase activity on nicked double-stranded DNA and on a singly primed DNA template. The enzyme activity is resistant to aphidicolin, and inhibited by dideoxynucleotides. Exhibites a single-stranded DNA-dependent ATPase activity. Could be involved in the repair of interstrand cross-links.[1]
Publication Abstract from PubMed
DNA polymerase theta (Poltheta) has been identified as a crucial alternative non-homologous end-joining factor in mammalian cells. Poltheta is upregulated in a range of cancer cell types defective in homologous recombination, and knockdown has been shown to inhibit cell survival in a subset of these, making it an attractive target for cancer treatment. We present crystal structures of the helicase domain of human Poltheta in the presence and absence of bound nucleotides, and a characterization of its DNA-binding and DNA-stimulated ATPase activities. Comparisons with related helicases from the Hel308 family identify several unique features. Poltheta exists as a tetramer both in the crystals and in solution. We propose a model for DNA binding to the Poltheta helicase domain in the context of the Poltheta tetramer, which suggests a role for the helicase domain in strand annealing of DNA templates for subsequent processing by the polymerase domain.
Structure of the Helicase Domain of DNA Polymerase Theta Reveals a Possible Role in the Microhomology-Mediated End-Joining Pathway.,Newman JA, Cooper CD, Aitkenhead H, Gileadi O Structure. 2015 Dec 1;23(12):2319-30. doi: 10.1016/j.str.2015.10.014. PMID:26636256[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Seki M, Marini F, Wood RD. POLQ (Pol theta), a DNA polymerase and DNA-dependent ATPase in human cells. Nucleic Acids Res. 2003 Nov 1;31(21):6117-26. PMID:14576298
- ↑ Newman JA, Cooper CD, Aitkenhead H, Gileadi O. Structure of the Helicase Domain of DNA Polymerase Theta Reveals a Possible Role in the Microhomology-Mediated End-Joining Pathway. Structure. 2015 Dec 1;23(12):2319-30. doi: 10.1016/j.str.2015.10.014. PMID:26636256 doi:http://dx.doi.org/10.1016/j.str.2015.10.014
