Sensory neurons control heritable adaptation to stress through germline reprogramming

Maternal neuronal signaling has been reported to program adaptive changes in offspring physiology in diverse organisms [1, 2]. However, the mechanisms for the inheritance of adaptive maternal effects through the germline are largely unknown. In the nematode Auanema freiburgensis , stress-resistance and sex of the offspring depend on environmental cues experienced by the mother. Maternal sensing of high population densities results in the production of stress-resistant larvae (dauers) that develop into hermaphrodites. Ablation of the maternal ASH chemosensory neurons results only in non-dauer offspring that develop into males or females. High population densities correlate with changes in the methylation status of H3K4 and H3K9 in the maternal germline. Inhibition of JMJD histone demethylases prevents mothers from producing dauers and hermaphrodite offspring in high-density conditions. Our results demonstrate a case of soma-to-germline transmission of environmental information that influences the phenotype of the following generation through changes in histone modifications of the maternal germline. Highlights High population density leads to the production of hermaphrodite offspring. The ASH neuron in the hermaphrodite mother senses population density. Histone modifications in the maternal germline correlate with the sex of offspring. Inhibition of histone demethylases results in female offspring in all conditions.