發(fā)布時間：2021-07-12 01:31

　　紅棕象甲Rhynchophorus ferrugineusOlivier（RPW）是嚴重危害棕櫚科植物的一種外來毀滅性害蟲。研究發(fā)現(xiàn),許多重要的農(nóng)林害蟲（包括RPW）腸道內(nèi)棲居著豐富的細菌群落,而且腸道菌群在它們的生活史中扮演重要角色。然而,害蟲如何耐受與調(diào)控腸道菌群維持共生關(guān)系的機制尚不清楚。大多數(shù)腸道細菌可以釋放肽聚糖（PGN）,而PGN正是昆蟲區(qū)分“異己”并激活免疫應(yīng)答的重要抗原。本研究旨在闡明具有酰胺酶活性的肽聚糖識別蛋白（PGRP）,RfPGRP-LB,在該害蟲的腸道菌群穩(wěn)態(tài)維持中的作用機理。保守結(jié)構(gòu)域分析發(fā)現(xiàn),RfPGRP-LB是一種含有典型PGRP結(jié)構(gòu)域的分泌蛋白,而且具有酰胺酶活性必需的五個保守氨基酸殘基,表明RfPGRP-LB是一種降解PGN的PGRP。RT-qPCR檢測表明,RfPGRP-LB在腸道中的轉(zhuǎn)錄水平顯著高于其他組織,而且大腸桿菌的注射感染能夠明顯誘導RJPGRP-LB的表達。體外功能分析證實,重組表達rRfPGRP-LB明顯抑制大腸桿菌的生長,這說明RfPGRP-LB是具有殺菌活性。干擾RfPGRP-LB基因后,喂食感染的綠色熒光標記大腸桿菌在紅棕象甲腸... 

【文章來源】：福建農(nóng)林大學福建省

【文章頁數(shù)】：51 頁

【學位級別】：碩士

【文章目錄】：
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



本文編號：3278916