Functional characterization of Gpr120 expressing cells and their role in fatty acid detection in knock-in mouse models

正常体重是通过能量需求和食物摄入量之间的微妙平衡来维持的。富含脂肪和碳水化合物的营养食物是行为自由的动物自发喜欢的食物。实验证据表明，这种行为反应在一定程度上是由适口性和味觉系统在整合了舌头上的味觉感受器提供的信息后引导的。这些观察结果与舌头上脂肪检测系统的存在是一致的。我们实验室和其他实验室之前的工作已经表明，长链脂肪酸转运蛋白CD36对于小鼠的嗅觉脂肪酸检测是重要的。然而，这种转运蛋白似乎不符合作为真正的味觉受体发挥作用的必要条件，最近的实验证据表明，啮齿动物对脂肪化合物的感知可能涉及多种途径。我们努力识别与舌头上的脂肪酸检测有关的其他受体，发现Gpr120可能是一个候选基因。Gpr120是一种G蛋白偶联受体，由长链脂肪酸激活，在味蕾细胞中表达。然而，它在味觉生理学中的作用仍有待研究。在这里，我们建议建立两个新的敲入小鼠模型，这将使我们能够分析Gpr120在脂肪酸检测中的生理作用。

Normal weight is maintained by a fine balance between energy needs and food intake. Nutritious foods rich in fat and carbohydrates are spontaneously preferred by freely behaving animals. Experimental evidence suggests that this behavioral response is in part guided by palatability and the taste system after integration of the information provided by the taste receptors on the tongue. These observations are consistent with the existence of a fat detection system on the tongue. Previous work from our laboratory and others has shown that the long chain fatty acid transporter CD36 is important for orosensory fatty acid detection in mice. However, this transporter does not appear to meet the necessary requirements to function as a bona fide taste receptor and recent experimental evidence suggests that multiple pathways may be involved in the perception of fat compounds in rodents. Our efforts to identify additional receptors involved in fatty acid detection on the tongue have uncovered Gpr120 as a possible candidate. Gpr120 is a G protein coupled receptor activated by long chain fatty acids and expressed in taste bud cells. However, its role in taste physiology remains to be investigated. Here we propose to generate two new knock-in mouse models, which will enable us to analyze the physiological role of Gpr120 in fatty acid detection.