Collaborative Research: Integrative Approaches to Plant Cell Wall Digestion by Non holometabolous Insects

合作研究：非全变态昆虫消化植物细胞壁的综合方法

• 批准号: 1456678
• 负责人: Brian Johnson
• 金额: $ 19.5万
• 依托单位: University of California-Davis
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-05-01 至 2019-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1456678&HistoricalAwards=false
• 关键词: Collaborative; Research; Integrative; Approaches; Plant

Plant cell walls contain lignocellulosic compounds that are difficult to degrade, such as xylan, cellulose, hemicellulose, and pectin. However, insect herbivores are capable of degrading these compounds and using the simpler compounds derived from the degradation processes for energy. While early work assumed that the source of the catalyst enzymes involved in the biochemical breakdown of lignocellulosic compounds (i.e., plant cell wall degradation enzymes, PCWDE) in insects was gut-resident symbiotic bacteria, recent work has shown that PCWDE produced by the cells of the insect gut are more important than previously realized. The goal of this research is to examine the diversity of PCWDE in two major lower insect lineages using a combination of functional genomics and biochemical tests. This basic research will improve understanding about the physiological mechanisms of insect digestion and may yield novel insights about insect control methods, biofuel industry improvements, and other industrial applications. This work will provide the opportunity for undergraduate, high school and graduate students to gain experience in cutting edge functional genomics, and insect physiology and biochemistry. Museum exhibits will be produced to educate the public about the importance of wood feeding insects. These exhibits will be presented at the University of California David Bohart Museum of Entomology and several other science museums across California and Tennessee. Preliminary work revealed that Phasmids (walking sticks) and Thysanurans (silverfish and firebrats) have strikingly high numbers of PCWDE, that these genes show compartment specific expression within the gut, and are effective at degrading plant cell wall compounds. This project will identify the full complement of PCWDE present in the focal species (6 Phasmids and 3 Thysanurans) and compare the activity and expression levels of them in the digestive systems of these insects. Using heterologous expression, the researchers will characterize the activity of the most active enzymes in these systems. The researchers will also analyze how patterns of gene expression correlate with the physical attributes of the gut, which vary greatly between the two focal insect orders. The ultimate goal is to describe the variation in physiological compartmentalization of the digestive system and determine how it works synergistically with a diversity of differentially-expressed enzymes to maximize digestion of lignocellulosic compounds. Findings from this research will be published in peer-reviewed journals, and presented at regional and national scientific meetings.

植物细胞壁含有难以降解的木质纤维素化合物，例如Xylan，纤维素，半纤维素和果胶。但是，昆虫食草动物能够降解这些化合物，并使用源自降解过程的较简单化合物的能量。虽然早期工作认为涉及木质纤维素化合物生化分解的催化剂酶（即昆虫中植物细胞壁降解酶，pCWDE）是肠道繁殖的共生细菌，但最近的工作表明，pcwdE造成了pcwde由昆虫的细胞所引起的。这项研究的目的是使用功能基因组学和生化测试的组合来检查两个主要昆虫谱系中PCWDE的多样性。这项基础研究将提高人们对昆虫消化的生理机制的理解，并可能产生有关昆虫控制方法，生物燃料行业改善和其他工业应用的新见解。这项工作将为本科，高中和研究生提供机会，以获得最先进的功能基因组学以及昆虫生理和生物化学的经验。博物馆的展览将被制作，以教育公众有关木材喂食昆虫的重要性。这些展览将在加利福尼亚大学大卫·博哈特昆虫学博物馆以及加利福尼亚和田纳西州的其他几个科学博物馆中展出。初步工作表明，Phasmid（手杖）和Thysanurans（Silverfish和Firebrats）的PCWDE数量惊人，这些基因在肠道内显示出特异性的表达，并且在降解植物细胞壁化合物方面有效。该项目将确定焦点物种中存在的PCWDE的完整补体（6个Phasmid和3个硫代氏菌），并比较它们在这些昆虫的消化系统中的活性和表达水平。使用异源表达，研究人员将表征这些系统中最活跃的酶的活性。研究人员还将分析基因表达的模式与肠道的物理属性如何相关，这在两种局部昆虫阶之间差异很大。最终目标是描述消化系统的生理分隔的变化，并确定其如何与多种差异表达的酶协同起作用，以最大程度地消化木质纤维素化合物。这项研究的结果将在同行评审期刊上发表，并在区域和国家科学会议上发表。