Chemical interrogation of metabolic tissue crosstalk

项目总结。外周代谢组织参与普遍的器官间串扰以维持 全身性血糖和血脂的动态平衡。这种远距离的细胞间通讯是由血液调节的。 携带、分泌的多肽。在过去的十年里，人们重新对确定其他 代谢组织分泌的蛋白质。这是因为分泌的蛋白质(例如分泌体)的集合 来自代谢细胞类型的多肽很大，而且特征也很差，因此有许多额外的多肽 调节外周组织串扰可能仍有待发现。想象一下……并非没有道理 这些孤儿因子中的许多代表了新的信号通路，因此可能是新的治疗方法 肥胖、糖尿病和相关代谢紊乱的目标。通常，解决此问题的方法依赖于 关于试图预测而不是直接测量体内多肽分泌的替代方法 事件。在最近的工作中，我们引入了一种体内化学方法学，使一种完全不同的 策略：直接在活体动物中测量代谢组织分泌体(魏等人，NAT。化学。比奥尔。2020)。 重要的是，这种化学策略为分泌体的组成和动态提供了独特的见解。 在小鼠身上，这是现有的体外或计算方法无法预测的。这项建议 寻求进一步开发这些化学方法，目标是生成完整的内分泌图 调节外周代谢组织串扰的分泌多肽。为了实现这一目标，我们将 (1)制作6器官15细胞型外周代谢组织多肽分泌组图谱并测定 这些分泌体是如何被代谢扰动(如肥胖、饮食、环境)动态改变的 温度和体力活动；(2)开发新的体内化学物质，使高分辨率地形图 通过蛋白水解性切割事件产生的分泌型多肽片段；以及(3)整合代谢组织 通过体内化学脉冲追逐途径分泌到内分泌回路。成功完成 这个高风险、高回报的项目将提供一个解剖细胞分泌体的化学工具箱， 组织串扰的潜在重要新领域，并最终实现长期愿景的“捕获” 组织串扰对抗肥胖、2型糖尿病和相关代谢紊乱的途径。

PROJECT SUMMARY. Peripheral metabolic tissues engage in pervasive inter-organ crosstalk to maintain systemic glucose and lipid homeostasis. This long-range intercellular communication is mediated by blood borne, secreted polypeptides. Over the last decade, there has been renewed interest in identifying additional proteins secreted from metabolic tissues. This is because the collection of secreted proteins (e.g., secretome) from metabolic cell types is large and also poorly characterized, and therefore many additional polypeptides that mediate peripheral tissue crosstalk likely remain to be discovered. It is not unreasonable to imagine that many of these orphan factors represent new signaling pathways and consequently potentially new therapeutic targets for obesity, diabetes, and related metabolic disorders. Typically, approaches to this problem have relied on surrogate methods that attempt to predict, rather than directly measure, in vivo polypeptide secretion events. In recent work, we have introduced an in vivo chemical methodology that enables a radically different strategy: to measure metabolic tissue secretomes directly in living animals (Wei et al., Nat. Chem. Biol. 2020). Importantly, this chemical strategy provides unique insights into the composition and dynamics of secretomes in mice that could not have been predicted by existing in vitro or computational approaches. This proposal seeks to further develop these chemical methodologies with the goal of generating a complete endocrine map of the secreted polypeptides that mediate peripheral metabolic tissue crosstalk. To achieve this goal, we will (1) produce a 6 organ, 15-cell type atlas of peripheral metabolic tissue polypeptide secretomes and determine how these secretomes are dynamically altered by metabolic perturbations such as obesity, diet, environmental temperature, and physical activity; (2) develop new in vivo chemistries that enable high-resolution mapping of secreted polypeptide fragments produced via proteolytic cleavage events; and (3) integrate metabolic tissue secretomes into endocrine circuits through in vivo chemical pulse-chase approaches. Successful completion of this high-risk, high-reward project will provide a chemical toolbox for dissecting cellular secretomes, open potentially important new areas in tissue crosstalk, and ultimately enable the long-term vision of “capturing” the pathways of tissue crosstalk to combat obesity, type 2 diabetes, and related metabolic disorders.