Immune-Related Transcriptome of Coptotermes formosanus Shiraki Workers: The Defense Mechanism

Abstract

Formosan subterranean termites, Coptotermes formosanus Shiraki, live socially in microbial-rich habitats. To understand the molecular mechanism by which termites combat pathogenic microbes, a full-length normalized cDNA library and four Suppression Subtractive Hybridization (SSH) libraries were constructed from termite workers infected with entomopathogenic fungi (Metarhizium anisopliae and Beauveria bassiana), Gram-positive Bacillus thuringiensis and Gram-negative Escherichia coli, and the libraries were analyzed. From the high quality normalized cDNA library, 439 immune-related sequences were identified. These sequences were categorized as pattern recognition receptors (47 sequences), signal modulators (52 sequences), signal transducers (137 sequences), effectors (39 sequences) and others (164 sequences). From the SSH libraries, 27, 17, 22 and 15 immune-related genes were identified from each SSH library treated with M. anisopliae, B. bassiana, B. thuringiensis and E. coli, respectively. When the normalized cDNA library was compared with the SSH libraries, 37 immune-related clusters were found in common; 56 clusters were identified in the SSH libraries, and 259 were identified in the normalized cDNA library. The immune-related gene expression pattern was further investigated using quantitative real time PCR (qPCR). Important immune-related genes were characterized, and their potential functions were discussed based on the integrated analysis of the results. We suggest that normalized cDNA and SSH libraries enable us to discover functional genes transcriptome. The results remarkably expand our knowledge about immune-inducible genes in C. formosanus Shiraki and enable the future development of novel control strategies for the management of Formosan subterranean termites.

Transcriptomic Immune Response of the Cotton Stainer Dysdercus fasciatus to Experimental Elimination of Vitamin-Supplementing Intestinal Symbionts

“…Furthermore, no distinct regulation patterns could be detected, with only few genes being differentially expressed (>2 fold) between symbiotic and aposymbiotic individuals. These observations are in line with other studies, demonstrating the constitutive expression of immune signaling pathway genes [34] .…”

Omic research in termites: an overview and a roadmap

“…The immune response is another aspect of host termite physiology investigated through transcriptomics. Four studies have revealed responses to immune challenges by both stereotypical and unprecedented immune-responsive genes ( Thompson et al, 2003 ; Yuki et al, 2008 ; Gao et al, 2012 ; Hussain et al, 2013 ). Finally, an emerging theme has been to investigate pathogen-xenobiotic interactions at the transcriptome level ( Husseneder and Simms, 2014 ; Sen et al, 2015 ).…”

The Effects of Trichoderma Fungi on the Tunneling, Aggregation, and Colony-Initiation Preferences of Black-Winged Subterranean Termites, Odontotermes formosanus (Blattodea: Termitidae)

“…However, some studies have shown that subterranean termites have evolved many physiological mechanisms to deal with the challenges pathogens present. Hussain et al [3] identified 439 immune-related sequences (i.e., pattern recognition receptors, signal modulators, signal transducers, and effectors) from Coptotermes formosanus Shiraki that were infected by entomopathogenic fungi and bacteria. Some termites and their symbiotic actinobacteria can produce various β-1,3-glucanases and antibiotics to prevent the germination of entomopathogenic fungi [4][5][6].…”