Teniposide

All dose-response experiments were performed on four genetically diverged strains (Bristol, Hawaii, DL238, and JU258) in technical quadruplicates prior to performing GWA and linkage mapping experiments (S4 Table). Animals were assayed using the HTA, and phenotypic analysis was performed as described above. Drug concentrations for GWA and linkage mapping experiments were chosen based on two criteria—an observable drug-specific effect and broad-sense heritability H². We aimed to use the first concentration for which a drug-specific effect with a maximum H² was observed. Broad-sense heritability estimates were calculated using the lmer function in the lme4 package with the following model (phenotype ~1 + (1|strain)). Concentrations for each chemotherapeutic used in mapping experiments are; etoposide—250 μM, teniposide—125 μM, amsacrine—50 μM, dactinomycin—15 μM, and XK469–1000 μM. All topoisomerase II poisons used in this study were purchased from Sigma (XK469 cat#X3628, etoposide cat#E1383, amsacrine cat#A9809, dactinomycin cat#A1410, and teniposide cat#SML0609).

NB4, HL60 and U937 are human myeloid leukemia cell lines. Hek293 is a human embryonic kidney cell line. HCT116 wild-type and p53-negative cells are human colon carcinoma cell lines. The “Natural products set III” was obtained from the National Cancer Institute (http://www.dtp.nci.nih.gov). Teniposide, etoposide, 9-amino-camptothecin, mitoxantrone and caffeine were obtained from Sigma and stored as 10 mM stock solutions (in DMSO) at −70 °C.

Embryos were treated by adding cell cycle inhibitors to the media from 11 hpf and incubated for 3–12 hr at 28.5°C. 20 μM hydroxyurea (Sigma-Aldrich, Cat# H8627), 300 μM aphidicolin (Sigma-Aldrich, Cat# A0781), 100 μM genistein (Calbiochem, Cat# 345834), teniposide (Sigma-Aldrich, Cat# SML0609), or 1% DMSO as control (Sigma-Aldrich, Cat# D8418). Notch signalling was inhibited at 11 hpf by adding 100 μM DAPT (Sigma-Aldrich, Cat# D5942-25MG) or 50 μM of Compound E (Abcam, Cat# ab142164). The latter reagent was used to perform live imaging, which is difficult to do with DAPT as it generates an interfering precipitate. 1% DMSO was added as control. Gene expression was induced by addition of 2.5 μM of tamoxifen (Sigma-Aldrich, Cat#H7904) to the media at 11 hpf of Sox10:Kalt4 embryos, or by heat shock at 11 hpf in hs:Gal4 and hs:dnSu(H) embryos by changing the media to 39°C E3, followed by 1 hr incubation at this temperature, thereafter embryos were grown at 28.5°C to the desired stage.