Small-molecule signals controlling nematode development

控制线虫发育的小分子信号

基本信息

批准号：
10532372
负责人：
Rebecca A Butcher
金额：
$ 38.13万
依托单位：
UNIVERSITY OF FLORIDA
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-12-01 至 2026-11-30
项目状态：
未结题

项目摘要

Project Summary/Abstract The nematode Caenorhabditis elegans relies on small-molecule signals to control its development, metabolism, physiology, and behavior, and these signals play conserved roles in many parasitic nematode species. This MIRA application outlines our ongoing efforts to understand the structures, biosynthesis, and mechanisms of several important classes of small-molecule signals, including (1) the ascarosides – a broad family of pheromones secreted by C. elegans that the worm uses to induce the stress-resistant dauer larval stage and to coordinate various behaviors, (2) the N-acyl glutamine nacq#1 – a pheromone that males preferentially secrete to counter the effects of dauer-inducing ascarosides on hermaphrodites and promote reproductive development, and (3) the nemamides – a family of hybrid polyketide-nonribosomal peptides that serve as hormones in the worm and promote starvation survival through a poorly understood mechanism. We target the biosynthetic pathways to these signaling molecules in vivo by generating precise mutations in the worm genome using CRISPR-Cas9 and analyzing the effects of these mutations on the primary and secondary metabolome of the worm using comparative metabolomics. This approach enables us to map the biosynthetic pathways to these natural products, to identify additional signaling molecules produced by these pathways, and to determine how these pathways intersect with other metabolic pathways in the worm. We rigorously confirm the role of specific enzymes in the pathways by reconstituting the pathways using in vitro enzymatic assays, organic synthesis of biosynthetic intermediates, and structural studies. With the support of this award, we will investigate the biosynthesis and mechanism of the nemamides, as well as the biological roles of the two essential and enigmatic neurons where the nemamides are produced, the canal-associated neurons (CANs). We will use nemamide biosynthesis, which requires genes that are distributed throughout the worm genome, to understand how the biosynthesis of complex secondary metabolites is controlled in the context of an animal system. Furthermore, we will investigate how this biosynthetic pathway intersects with the biosynthetic pathways of other secondary metabolites, including the ascarosides and nacq#1. A central focus will be how the worm regulates the production and trafficking of these different small-molecule signals in response to different factors and environmental conditions in order to coordinate its development, metabolism, and physiology. This work will provide insights into how C. elegans and other nematode species use small-molecule signals to control important conserved downstream signaling pathways, such as the insulin pathway. Furthermore, given the conservation of these small-molecule signals in parasitic nematode species, this work will provide new chemical tools and strategies to interfere with the life cycles of those nematodes.

项目概要/摘要线虫秀丽隐杆线虫依靠小分子信号来控制其发育、代谢、生理学和行为，这些信号在许多寄生线虫物种中发挥着保守的作用。 MIRA 应用概述了我们为了解结构、生物合成和机制所做的持续努力几类重要的小分子信号，包括 (1) 蛔苷——一个广泛的家族线虫分泌的信息素，线虫用它来诱导抗应激的多尔幼虫阶段并协调各种行为，(2) N-酰基谷氨酰胺 nacq#1 – 雄性优先分泌的信息素对抗多尔诱导蛔苷对雌雄同体的影响并促进生殖发育， (3) nemamides – 杂合聚酮化合物-非核糖体肽家族，在体内充当激素我们通过一种鲜为人知的机制来对抗蠕虫并促进饥饿生存。通过使用在线虫基因组中产生精确的突变，在体内到达这些信号分子的途径 CRISPR-Cas9 并分析这些突变对初级和次级代谢组的影响这种方法使我们能够利用比较代谢组学来绘制线虫的生物合成途径。天然产物，识别这些途径产生的其他信号分子，并确定如何这些途径与蠕虫中的其他代谢途径交叉，我们严格确认了特定的作用。通过使用体外酶测定、有机合成来重构途径，来检测途径中的酶在该奖项的支持下，我们将研究生物合成中间体和结构研究。 nemamides的生物合成和机制，以及这两种重要且神秘的生物学作用产生线酰胺的神经元，即管相关神经元（CAN），我们将使用线酰胺。生物合成需要分布在整个蠕虫基因组中的基因，以了解复杂的次生代谢物的生物合成在动物系统中受到控制。我们将研究该生物合成途径如何与其他次级生物合成途径交叉代谢物，包括蛔苷和 nacq#1 是蠕虫如何调节的。这些不同的小分子信号的产生和运输响应不同的因素和这项工作将调整环境条件，以协调其发育、新陈代谢和生理学。提供有关秀丽隐杆线虫和其他线虫物种如何利用小分子信号来控制重要线虫的见解保守的下游信号通路，例如胰岛素通路此外，考虑到保守性。寄生线虫物种中的这些小分子信号，这项工作将提供新的化学工具和干扰这些线虫生命周期的策略。