E3 ubiquitin-protein ligase which accepts ubiquitin from an E2 ubiquitin-conjugating enzyme in the form of a thioester and then directly transfers the ubiquitin to targeted substrates (PubMed:24805825, PubMed:19553937). Ubiquitinates klf-1 (PubMed:24805825). Required for diet restriction-mediated lifespan extension, acting in concert with Kruppel-like factor klf-1 in the intestine to perhaps modulate genes involved in lipid metabolism (PubMed:24805825, PubMed:19553937). Probably acting downstream of the Insulin/IGF-1-like signaling (IIS) mediated pathway, plays a role in the immune response to infection by the Gram-negative bacterium P.aeruginosa, at least partly in response to bacterial pore-forming toxins (PubMed:20209166). S-ubiquitinyl-[E2 ubiquitin-conjugating enzyme]-L-cysteine + [acceptor protein]-L-lysine = [E2 ubiquitin-conjugating enzyme]-L-cysteine + N(6)-ubiquitinyl-[acceptor protein]-L-lysine. Protein modification; protein ubiquitination. Interacts (via WW domains) with Kruppel-like factor klf-1 (PubMed:24805825). Interacts with ubiquitin-conjugating enzyme E2 ubc-18 (PubMed:19553937). Expressed in neurons localized in the head and tail of adults. RNAi-mediated knockdown increases sensitivity to paraquat, and reduces lifespan at 25 degrees Celsius, but not at 20 degrees Celsius (PubMed:19553937). Causes reduced ability of dietary restriction to extend lifespan (PubMed:24805825, PubMed:19553937). Abolishes lifespan extension completely on an eat-2 mutant background, independent of whether knockdown is ubiquitous, or targeted only to the intestine (PubMed:24805825, PubMed:19553937). Does not suppress extended lifespans of isp-1 or daf-2 mutants (PubMed:19553937). Hypersensitive to bacterial pore-forming toxin (PubMed:20209166).