Faithin Omaha eBook Collection

Download or read book Mechanisms by which Feeding State and Sex are Integrated to Regulate Chemosensory Plasticity in C. Elegans written by Leigh R. Wexler and published by . This book was released on 2019 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt: The feeding-state of an animal can have deep effects on its chemosensation and behavioral decisions. Although many internal signals of nutritional state and hunger are known, the mechanisms by which these modulate neural circuits and behavior are less well understood. C. elegans display an interesting intersection of feeding state and sex in the regulation of chemosensory behavior. Self-fertile hermaphrodites exhibit strong food attraction while males prioritize mate-searching over feeding. This sexual dimorphism is regulated in part through differences the chemoreceptor ODR-10, which detects the food-associated odorant diacetyl in the AWA neuron. Hermaphrodites expresses high levels of odr-10 while in adult males, expression of odr-10 is low, promoting exploratory behavior. However, starved males transiently upregulate odr-10 to generate stronger food attraction until their nutritional needs are met. This multi-layered regulation of odr-10 provides an opportunity to study how neural circuits integrate genetic sex and feeding-state to regulate chemosensory behaviors through chemoreceptor expression. We show that in response to food availability, odr-10 is modulated in males through insulin-like signaling and DAF-7/TGF? signaling. Interestingly, we find that in males odr-10 is regulated primarily by sensory perception of food, not metabolic starvation. Similarly, the TGF? ligand daf-7 is regulated in the ASJ neuron by food perception, linking environmental signals to odr-10. Additionally, these mechanisms are modulated by sex. We show hermaphrodites also regulate odr-10 in response to feeding state, however they do so through divergent mechanisms from males, independent of insulin and TFG? signaling and in response to metabolic starvation. Through this work we identify a male-specific mechanisms which modulates chemosensation based on environmental conditions furthering our understanding of how chemoreceptor expression and behavioral choice is regulated through multiple internal and external states.