Differential control of dNTP biosynthesis and genome integrity maintenance by the dUTPase superfamily enzymes

Abstract dUTPase superfamily enzymes generate dUMP, the obligate precursor for de novo dTTP biosynthesis, from either dUTP (monofunctional dUTPase, Dut) or dCTP (bifunctional dCTP deaminase/dUTPase, Dcd:dut). In addition, the elimination of dUTP by these enzymes prevents harmful uracil incorporation...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Rita Hirmondo, Anna Lopata, Eva Viola Suranyi, Beata G. Vertessy, Judit Toth
Formato: article
Lenguaje:EN
Publicado: Nature Portfolio 2017
Materias:
R
Q
Acceso en línea:https://doaj.org/article/bef3ef7961d0413e9b1437ec1505ae42
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
Descripción
Sumario:Abstract dUTPase superfamily enzymes generate dUMP, the obligate precursor for de novo dTTP biosynthesis, from either dUTP (monofunctional dUTPase, Dut) or dCTP (bifunctional dCTP deaminase/dUTPase, Dcd:dut). In addition, the elimination of dUTP by these enzymes prevents harmful uracil incorporation into DNA. These two beneficial outcomes have been thought to be related. Here we determined the relationship between dTTP biosynthesis (dTTP/dCTP balance) and the prevention of DNA uracilation in a mycobacterial model that encodes both the Dut and Dcd:dut enzymes, and has no other ways to produce dUMP. We show that, in dut mutant mycobacteria, the dTTP/dCTP balance remained unchanged, but the uracil content of DNA increased in parallel with the in vitro activity-loss of Dut accompanied with a considerable increase in the mutation rate. Conversely, dcd:dut inactivation resulted in perturbed dTTP/dCTP balance and two-fold increased mutation rate, but did not increase the uracil content of DNA. Thus, unexpectedly, the regulation of dNTP balance and the prevention of DNA uracilation are decoupled and separately brought about by the Dcd:dut and Dut enzymes, respectively. Available evidence suggests that the discovered functional separation is conserved in humans and other organisms.