DNA Polymerase θ: A Unique Multifunctional End-Joining Machine
AbstractThe gene encoding DNA polymerase θ (Polθ) was discovered over ten years ago as having a role in suppressing genome instability in mammalian cells. Studies have now clearly documented an essential function for this unique A-family polymerase in the double-strand break (DSB) repair pathway alternative end-joining (alt-EJ), also known as microhomology-mediated end-joining (MMEJ), in metazoans. Biochemical and cellular studies show that Polθ exhibits a unique ability to perform alt-EJ and during this process the polymerase generates insertion mutations due to its robust terminal transferase activity which involves template-dependent and independent modes of DNA synthesis. Intriguingly, the POLQ gene also encodes for a conserved superfamily 2 Hel308-type ATP-dependent helicase domain which likely assists in alt-EJ and was reported to suppress homologous recombination (HR) via its anti-recombinase activity. Here, we review our current knowledge of Polθ-mediated end-joining, the specific activities of the polymerase and helicase domains, and put into perspective how this multifunctional enzyme promotes alt-EJ repair of DSBs formed during S and G2 cell cycle phases. View Full-Text
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Black, S.J.; Kashkina, E.; Kent, T.; Pomerantz, R.T. DNA Polymerase θ: A Unique Multifunctional End-Joining Machine. Genes 2016, 7, 67.
Black SJ, Kashkina E, Kent T, Pomerantz RT. DNA Polymerase θ: A Unique Multifunctional End-Joining Machine. Genes. 2016; 7(9):67.Chicago/Turabian Style
Black, Samuel J.; Kashkina, Ekaterina; Kent, Tatiana; Pomerantz, Richard T. 2016. "DNA Polymerase θ: A Unique Multifunctional End-Joining Machine." Genes 7, no. 9: 67.
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