A male seminal fluid protein SFP-1 regulates hermaphrodite post-mating longevity and fat metabolism in Caenorhabditis elegans

There are several causes of mating-induced physiological changes in hermaphrodites exposed to males, such as functional male sperms causing shrinking and the male pheromone mediating shortened lifespan, which utilize different molecular pathways and are shared across species. However, it is unclear whether the male seminal fluid protein contributes to this post-mating regulation. Here, we investigated the transmit way and the impacts of the Caenorhabditis male seminal fluid protein SFP-1 in mated hermaphrodite tissues. We find that SFP-1 is the key component in seminal fluid to induce post-mating physiological changes in mated hermaphrodites. It acts as a cargo packing into exophers which require the phospholipid scramblase ANOH-1 and ANOH-2 to develop in male seminal vesicle. Exophers carrying SFP-1 cross over the somatic gonad uterus and eventually the protein is uptaken by the intestinal cells via endocytosis. Within the intestine, the NTF2-like domain of SFP-1 assists the association and interaction with the transcription factors SKN-1 and DAF-16 to induce post-mating somatic fat depletion and a shortened lifespan. Our study reveals the elaborate strategies of the male seminal fluid protein on triggering mating-induced physiological changes elicited by sexual interactions that could exist in other species.