Elucidation of energy homeostasis of corpora cardiaca and corpora allata in insect

在恶劣的环境和有限的营养条件下，通过调节神经肽来维持能量稳态对动物的生存至关重要。关于神经肽如何响应循环中的营养物质并导致随后的生理事件，我们知之甚少。在此，我们引入了包括两种神经肽的调节途径，甲壳类心脏活性肽（CCAP）和肌抑制素。基于先前的结果，CCAP在再喂养后通过响应循环葡萄糖水平的升高而增强。多发性硬化症也参与控制能量稳态。然后我们发现，随后由GbCCAP引起的海藻糖升高诱导了GbMS的表达。高浓度葡萄糖可观察到GbCCAP信号增强，表明CCAP和MS响应循环中不同的碳水化合物，这可能是神经激素激活循环改变的可能性。鉴于ILP和AKH在碳水化合物稳态调节中的主导作用，我们随后研究了ILP和AKH作为GbCCAP和GbMS的下游调控碳水化合物稳态的可能性。令人惊讶的是，GbCCAP被证明是独立于GbILP和GbAKH的，这是一个深刻的发现，昆虫中可能存在一种新的碳水化合物调控途径。随后，敲除GbCCAP和GbMS受体后，海藻糖磷酸合酶增强。结果表明，GbCCAP的调节作用需要GbTps的作用，这意味着GbCCAP通过参与海藻糖合成途径发挥其碳水化合物调节功能。

Maintaining energy homeostasis in inhospitable environment and limited nutrient by orchestration of neuropeptides is crucial for survival of animals. Little is known about how neuropeptide respond to circulating nutrients and lead subsequent physiology event. Here we introduced a regulatory pathway including two neuropeptides, Crustacean cardioactive peptide (CCAP) and MyosuppressinBased on the previous result that CCAP was enhanced after refeeding by responding to the increased circulating glucose level. And MS was also involved in controlling energy homeostasis. We then found that the subsequent elevation of trehalose caused by GbCCAP induced the expression of GbMS. An enhanced signal of GbCCAP was observed by high concentrated glucose, suggesting that CCAP and MS answer to different carbohydrate in circulation, which give the possibility of neurohormonal activation of circulating alterations.Given the predominant roles of ILP and AKH in the carbohydrate homeostasis regulation, we then examined the possibility of ILP and AKH as the downstream of GbCCAP and GbMS in the regulation of carbohydrate homeostasis. Surprisingly, GbCCAP was proved to be independent of GbILP and GbAKH, which is a profound find that a novel carbohydrate regulatory pathway may be exist in insects. Followingly, trehalose phosphate synthase was enhanced when knockdown the receptors of GbCCAP and GbMS. Results showed that regulatory role of GbCCAP requires the function of GbTps, which imply that GbCCAP exert its carbohydrate regulatory function by the involvement of trehalose synthesis pathway.