Differential gene expression in silkworm in response to Beauveria bassiana infection

Abstract Host–pathogen interactions are complex processes, and revealing these interactions is challenging. Beauveria bassiana is a destructive pathogen to the economically beneficial silkworm, Bombyx mori , but is also a good pathogenic material for investigating insect responses to fungal infection. For better understanding of the molecular regulation of immune response and the interactive mechanism between the silkworm and B. bassiana , suppression subtractive hybridization was employed to identify differentially expressed genes in the pathogen-stimulated silkworm larvae. Complementary DNA libraries were constructed, in which 240 clones were sequenced. A total of 77 genes were found to be involved in the infection process, among which 55 were known genes and 22 were novel. Expression profiling of 6 genes by quantitative PCR showed that they were induced by fungal challenge. This study establishes the first step to understanding the molecular mechanisms by which silkworm responds to fungal infection.