Transcriptomic Insights into the Insect Immune Response to Nematode Infection

Abstract

Insects in nature interact with a wide variety of microbial enemies including nematodes. These include entomopathogenic nematodes that contain mutualistic bacteria and together are able to infect a broad range of insects in order to complete their life cycle and multiply, filarial nematodes which are vectored by mosquitoes, and other parasitic nematodes. Entomopathogenic nematodes are commonly used in biological control practices and they form excellent research tools for understanding the genetic and functional bases of nematode pathogenicity and insect anti-nematode immunity. In addition, clarifying the mechanism of transmission of filarial nematodes by mosquitoes is critical for devising strategies to reduce disease transmission in humans. In all cases and in order to achieve these goals, it is vital to determine the number and type of insect host genes which are differentially regulated during infection and encode factors with anti-nematode properties. In this respect, the use of transcriptomic approaches has proven a key step for the identification of insect molecules with anti-nematode activity. Here, we review the progress in the field of transcriptomics that deals with the insect response to nematode infection. This information is important because it will expose conserved pathways of anti-nematode immunity in humans.

Keywords: immunity; infection; insect; nematodes; transcriptomics.

Figure 1

Differentially regulated genes of the insect immune response against entomopathogenic nematodes identified by (A) RNA-Seq analysis in D. melanogaster adult flies infected by H. bacteriophora symbiotic or axenic nematodes; (B) Microarray analysis in D. melanogaster larvae infected by H. bacteriophora symbiotic nematodes; (C) RNA-Seq analysis in H. virescens caterpillars infected by H. bacteriophora symbiotic nematodes.