Role of vitellogenins on the mitochondrial unfolded protein response.

Sex-specific differences influence aging and disease onset. Using Caenorhabditis elegans , we previously found that hermaphroditic nematodes activate a robust mitochondrial unfolded protein response (UPR mt ) in the intestines, while female nematodes do not. We hypothesized that the accumulation of vitellogenins in females was suppressing the UPR mt . Loss of vitellogenins via RNAi enhanced the UPR mt in hermaphrodites but had no impact on the UPR mt of females unless a combination of vitellogenins was simultaneously knocked down. Furthermore, combinatorial loss of vitellogenins did not restore the female UPR mt to hermaphroditic levels. We conclude that additional factors besides vitellogenins are involved in suppressing the intestinal UPR mt in female nematodes.