Multiple excitatory and inhibitory neural signals converge to fine-tune Caenorhabditis elegans feeding to food availability.
نویسندگان
چکیده
How an animal matches feeding to food availability is a key question for energy homeostasis. We addressed this in the nematode Caenorhabditis elegans, which couples feeding to the presence of its food (bacteria) by regulating pharyngeal activity (pumping). We scored pumping in the presence of food and over an extended time course of food deprivation in wild-type and mutant worms to determine the neural substrates of adaptive behavior. Removal of food initially suppressed pumping but after 2 h this was accompanied by intermittent periods of high activity. We show pumping is fine-tuned by context-specific neural mechanisms and highlight a key role for inhibitory glutamatergic and excitatory cholinergic/peptidergic drives in the absence of food. Additionally, the synaptic protein UNC-31 [calcium-activated protein for secretion (CAPS)] acts through an inhibitory pathway not explained by previously identified contributions of UNC-31/CAPS to neuropeptide or glutamate transmission. Pumping was unaffected by laser ablation of connectivity between the pharyngeal and central nervous system indicating signals are either humoral or intrinsic to the enteric system. This framework in which control is mediated through finely tuned excitatory and inhibitory drives resonates with mammalian hypothalamic control of feeding and suggests that fundamental regulation of this basic animal behavior may be conserved through evolution from nematode to human.
منابع مشابه
Neuroecology: Tuning Foraging Strategies to Environmental Variability
Caenorhabditis elegans has been shown to measure variability in environmental food density, using the information to fine-tune foraging strategies; a compact neural circuit has been identified that responds to large fluctuations in food-related cues and uses dopamine to encode the amount of recently encountered variability.
متن کاملDetermination of the effects of food preservatives benzoic acid and sodium nitrate on lifespan, fertility and physical growth in Caenorhabditis elegans
Presently, the use of protective food additives such as benzoic acid and sodium nitrate is quite common. However, it was found that these additives, which initially appeared to be harmless, led to the emergence of a number of health problems. Cancer and diseases and deaths with no apparent causes are among the leading concerns. Therefore, the studies which can reveal the genotoxic potential of ...
متن کاملA gene-expression-based neural code for food abundance that modulates lifespan
How the nervous system internally represents environmental food availability is poorly understood. Here, we show that quantitative information about food abundance is encoded by combinatorial neuron-specific gene-expression of conserved TGFβ and serotonin pathway components in Caenorhabditis elegans. Crosstalk and auto-regulation between these pathways alters the shape, dynamic range, and popul...
متن کاملDishevelled attenuates the repelling activity of Wnt signaling during neurite outgrowth in Caenorhabditis elegans.
Wnt proteins regulate axonal outgrowth along the anterior-posterior axis, but the intracellular mechanisms that modulate the strength of Wnt signaling in axon guidance are largely unknown. Using the Caenorhabditis elegans mechanosensory PLM neurons, we found that posteriorly enriched LIN-44/Wnt acts as a repellent to promote anteriorly directed neurite outgrowth through the LIN-17/Frizzled rece...
متن کاملSynaptic polarity of the interneuron circuit controlling C. elegans locomotion
Caenorhabditis elegans is the only animal for which a detailed neural connectivity diagram has been constructed. However, synaptic polarities in this diagram, and thus, circuit functions are largely unknown. Here, we deciphered the likely polarities of seven pre-motor neurons implicated in the control of worm's locomotion, using a combination of experimental and computational tools. We performe...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- FASEB journal : official publication of the Federation of American Societies for Experimental Biology
دوره 30 2 شماره
صفحات -
تاریخ انتشار 2016