Gruner Matthew, van der Linden Alexander M
Department of Biology; University of Nevada ; Reno, NV USA.
Worm. 2015 Mar 6;4(2):e1023497. doi: 10.1080/21624054.2015.1023497. eCollection 2015 Apr-Jun.
Animals dramatically modify their chemosensory behaviors when starved, which could allow them to alter and optimize their food-search strategies. Dynamic changes in the gene expression of chemoreceptors may be a general mechanism underlying food and state-dependent changes in chemosensory behaviors. In our recent study,(1) we identified chemoreceptors in the ADL sensory neuron type of C. elegans that are modulated by feeding state and food availability. Here, we highllight our recent findings by which sensory inputs into ADL, neuronal outputs from ADL, and circuit inputs from the RMG interneuron, which is electrically connected to ADL, are required to regulate an ADL-expressed chemoreceptor. This sensory and circuit-mediated regulation of chemoreceptor gene expression is dependent on cell-autonomous pathways acting in ADL, e.g. KIN-29, DAF-2, OCR-2 and calcium signaling, and circuit inputs from RMG mediated by NPR-1. Based on these findings, we propose an intriguing but speculative feedback modulatory circuit mechanism by which sensory perception of food and internal state signals may be coupled to regulate ADL-expressed chemoreceptors, which may allow animals to precisely regulate and fine-tune their chemosensory neuron responses as a function of feeding state.
动物在饥饿时会显著改变其化学感应行为，这可能使它们能够改变并优化其食物搜索策略。化学感受器基因表达的动态变化可能是化学感应行为中食物和状态依赖性变化的一种普遍机制。在我们最近的研究中，（1）我们在秀丽隐杆线虫的ADL感觉神经元类型中鉴定出了受进食状态和食物可获得性调节的化学感受器。在这里，我们重点介绍我们最近的发现，即调节一个ADL表达的化学感受器需要ADL的感觉输入、ADL的神经元输出以及来自与ADL电连接的RMG中间神经元的回路输入。化学感受器基因表达的这种感觉和回路介导的调节依赖于ADL中起作用的细胞自主途径，例如KIN-29、DAF-2、OCR-2和钙信号传导，以及由NPR-1介导的来自RMG的回路输入。基于这些发现，我们提出了一种有趣但具有推测性的反馈调节回路机制，通过该机制，食物的感觉感知和内部状态信号可能相互耦合，以调节ADL表达的化学感受器，这可能使动物能够根据进食状态精确调节和微调其化学感应神经元反应。
