RESUMEN

dUTPase is involved in preserving DNA integrity in cells. We report an efficient dUTPase silencing by RNAi-based system in stable human cell line. Repression of dUTPase induced specific expression level increments for thymidylate kinase and thymidine kinase, and also an increased sensitization to 5-fluoro-2'-deoxyuridine and 5-fluoro-uracil. The catalytic mechanism of dUTPase was investigated for 5-fluoro-dUTP. The 5F-substitution on the uracil ring of the substrate did not change the kinetic mechanism of dUTP hydrolysis by dUTPase. Results indicate that RNAi silencing of dUTPase induces a complex cellular response wherein sensitivity towards fluoropyrimidines and gene expression levels of related enzymes are both modulated.

Asunto(s)

Nucleósido-Fosfato Quinasa/genética , Pirofosfatasas/genética , Interferencia de ARN , Timidina Quinasa/genética , Floxuridina/metabolismo , Fluorouracilo/metabolismo , Regulación de la Expresión Génica , Células HeLa , Humanos , Nucleósido-Fosfato Quinasa/metabolismo , Pirofosfatasas/metabolismo , Timidina Quinasa/metabolismo