MicroRNAs as mediators of insect host–pathogen interactions and immunity

[Display omitted] •MiRNAs are small non-coding RNAs that regulate gene expression.•Following infection, miRNA profile of the host is altered either due to defence or manipulation by the pathogen.•Virus-encoded miRNAs regulate host or viral genes facilitating establishment of infection. Insects are the most successful group of animals on earth, owing this partly to their very effective immune responses to microbial invasion. These responses mainly include cellular and humoral responses as well as RNA interference (RNAi). Small non-coding RNAs (snRNAs) produced through RNAi are important molecules in the regulation of gene expression in almost all living organisms; contributing to important processes such as development, differentiation, immunity as well as host–microorganism interactions. The main snRNAs produced by the RNAi response include short interfering RNAs, microRNAs and piwi-interacting RNAs. In addition to the host snRNAs, some microorganisms encode snRNAs that affect the dynamics of host–pathogen interactions. In this review, we will discuss the latest developments in regards to the role of microRNA in insect host–pathogen interactions and provide some insights into this rapidly developing area of research.