Reproductive tradeoffs govern sexually dimorphic tubular lysosome induction in C. elegans

Animals of different sexes often exhibit unique behaviors that benefit their specific reproductive interests. In the nematode Caenorhabditis elegans, self-fertilizing hermaphrodites can reproduce without a mate and thus prioritize feeding to satisfy the high energetic costs of reproduction. However, males, which rely on finding potential mates for reproduction, sacrifice feeding and instead prioritize exploratory behavior. Here, we demonstrate that these differences in behavior are linked to sexual dimorphism at the cellular level; young males raised on a rich food source show constitutive induction of gut tubular lysosomes, a non-canonical lysosome morphology that typically forms in the gut of young hermaphrodites only when food is limited. We find that male-specific induction of gut tubular lysosomes on abundant food is due to self-imposed dietary restriction through daf-7/TGF{beta} signaling, which promotes mate-searching at the cost of feeding. While gut tubular lysosomes are largely absent from well-fed hermaphrodites at the start of adulthood, their induction accelerates in hermaphrodites in early aging, dependent on the presence of sperm and, partly, on embryo production. These findings identify tubular lysosome induction as a sexually dimorphic cellular event that may integrate animal physiology with sex-specific behavioral differences important for reproductive success.