S1 Fig -
(A, B) Schematic representation of different culture and selection procedures. (A) Transgenic worms carrying rps-0p::hygR conferring hygromycin resistance together with unc-122p::GFP as an extrachromosomal array (IG1864) were grown on NGM plates supplemented with hygromycin (left) or on standard NGM plates after manual selection on the basis of the expression of the fluorescent marker. (B) IG1864 worms were cultured overnight in liquid in the presence (left) or absence of hygromycin. Worms were transferred to NGM plates and in the latter case selected manually, as above. (C) Quantitative RT-PCR analysis comparing the expression of irg-1 in IG1864 worms selected by growth on hygromycin-supplemented NGM plates to that in worms selected manually (-), and in IG1864 worms selected by synchronization in the presence of hygromycin to that in worms selected manually following synchronization in the absence of hygromycin (+). The results from 2 independent experiments are shown. It can be seen that even in worms that are resistant to hygromycin, prolonged culture in the presence of the antibiotic increases irg-1 expression, while overnight exposure during early development does not.