Fluorodeoxyuridine affects the identification of metabolic responses to daf-2 status in Caenorhabditis elegans

Fluorodeoxyuridine (FUdR) is often used to help maintain synchronous populations of Caenorhabditis elegans adults, for instance as would typically be the case in studying age-related effects. However, given that FUdR inhibits DNA synthesis and therefore reproduction, it will clearly have significant wide-ranging biological effects. It is often assumed that these can be compensated for using appropriate controls. We show here that this is not the case for a metabolomic analysis of a long-lived daf-2 mutant strain: not only were the effects of FUdR much greater than the effects of the mutation, there were clear interactions between FUdR and genotype, such that identification of daf-2-dependent metabolites would have been compromised on FUdR plates. This indicates that FUdR should only be used with caution for C elegans ageing experiments, and should not be assumed to be independent of other factors being studied. (C) 2011 Elsevier Ireland Ltd. All rights reserved.