RfPGRP-LB负调控红棕象甲Rhynchophorus ferrugineus Olivier肠道免疫维持肠道菌群稳

发布时间：2021-07-12 01:31

　　红棕象甲Rhynchophorus ferrugineusOlivier（RPW）是严重危害棕榈科植物的一种外来毁灭性害虫。研究发现,许多重要的农林害虫（包括RPW）肠道内栖居着丰富的细菌群落,而且肠道菌群在它们的生活史中扮演重要角色。然而,害虫如何耐受与调控肠道菌群维持共生关系的机制尚不清楚。大多数肠道细菌可以释放肽聚糖（PGN）,而PGN正是昆虫区分“异己”并激活免疫应答的重要抗原。本研究旨在阐明具有酰胺酶活性的肽聚糖识别蛋白（PGRP）,RfPGRP-LB,在该害虫的肠道菌群稳态维持中的作用机理。保守结构域分析发现,RfPGRP-LB是一种含有典型PGRP结构域的分泌蛋白,而且具有酰胺酶活性必需的五个保守氨基酸残基,表明RfPGRP-LB是一种降解PGN的PGRP。RT-qPCR检测表明,RfPGRP-LB在肠道中的转录水平显着高于其他组织,而且大肠杆菌的注射感染能够明显诱导RJPGRP-LB的表达。体外功能分析证实,重组表达rRfPGRP-LB明显抑制大肠杆菌的生长,这说明RfPGRP-LB是具有杀菌活性。干扰RfPGRP-LB基因后,喂食感染的绿色荧光标记大肠杆菌在红棕象甲肠... 

【文章来源】：福建农林大学福建省

【文章页数】：51 页

【学位级别】：硕士

【文章目录】：
Chinese Abstract
Abstract
1. General introduction
    1.1 Gut microbiota and their physiological roles
    1.2 Gut immune defences and maintenance of gut microbiota
    1.3 Importance of gut homeostasis study
    1.4 Research hypothesis and objectives
2. Materials and Methods
    2.1 Insect collection and rearing
    2.2 Cloning and sequence analysis of RfPGRP-LB cDNA
    2.3 Expression analysis of RfPGRP-LB and antimicrobial peptides by reversetranscription (RT)-qPCR
    2.4 In-vitro functional assays of recombinant RfPGRP-LB
    2.5 The effects of RfPGRP-LB knockdown on the persistence of nonresidentialbacteria and load of the indigenous gut microbiota
    2.6 RJPGRP-LB knockdown-mediated changes in the community structure of RPW gut microbiota by 16S rRNA gene-based Illumina high-throughput sequencing
    2.7 Statistical analysis
3. Results
    3.1 RfPGRP-LB is a secreted catalytic PGRP induced by bacterial infection
    3.2 In-vitro verification of rRfPGRP-LB immune function by antibacterial assay
    3.3 Effects of RfPGRP-LB knockdown on the persistence of nonresidential bacteria,load of indigenous gut microbiota and the abundance of antimicrobial peptides ingut
    3.4 RfPGRP-LB knockdown-mediated alterations in the community structure ofRPW gut microbiota
4. Discussion
5. Conclusion
References
Acknowledgements
Publication during study period



本文编号：3278916