Detection of SUMOylation of ZTF-8 in vivo. (A) Lysates from transgenic worms expressing endogenous FLAG-tagged ZTF-8 (rj22), either treated or not with NEM to prevent de-SUMOylation (lanes 1 and 2, respectively), from NEM-treated K4Rs mutants (rj23, lane3), and from nontransgenic wild-type worms (lane 4, negative control) were examined on Westerns immunoblotted with an anti-FLAG antibody. An anti-α-tubulin antibody was used for a loading control (right). (B) Lysates from transgenic worms expressing FLAG-tagged ZTF-8 either untreated (−IR and −HU), after 30 min of exposure to γ-IR (50 Gy) or treated with 10 mM HU, all in the presence of NEM. The same lysates were also subjected to immunoblotting with an anti-α-tubulin antibody (right).