A micronutrient-driven interspecies interaction that regulates behavior and longevity

Organismal aging is regulated by a complex interplay between the host and its commensal microbiota, and only recently have scientists started to uncover the molecular mechanisms underlying this relationship. The microbiota is a valuable source of vitamin B12, which is crucial for various life history traits, including longevity. The bacterivorous nematode C. elegans has been instrumental in our understanding of the vitamin B12-driven interspecies relationship that drives cellular signaling and gene expression to influence metabolism, behavior, and aging. While these worms encounter and feed on bacteria with different micronutrient compositions in their natural habitat, they are typically able to maintain a normal lifespan through metabolic adaptations guided by host genes. However, in laboratory settings, researchers may observe genetic mutants with distinct phenotypes when fed on different bacterial diets. Such diet-gene interactions are critical to our understanding of how nutrition affects longevity.  One such critical diet-gene pair involves a host protein kinase gene and vitamin B12 supplied by bacteria, and in this discussion, I will share our current understanding of this aspect of the micronutrient-mediated communication between two species that modulate behavior and longevity.