Gene expression profiling during early response to injury and microbial challenges in the silkworm, Bombyx mori

Abstract

To identify Bombyx mori genes involved in the early response to injury and microbial challenge, we performed genome-wide gene expression-profiling experiments using oligonucleotide DNA microarrays. Of approximately 23,000 genes examined, 465 displayed changes in mRNA expression levels. Of these, 306 were induced and 159 were repressed in response to injury (injection with phosphate buffer saline) or challenges by Gram-negative (Serratia marcescens), Gram-positive bacteria (Staphylococcus aureus), or fungus (Beauveria bassiana). Many of these differentially expressed genes can be assigned to specific functional groups of the innate immune response, including recognition, signaling, melanization and coagulation, and antimicrobial peptides. Seventeen percent of differentially expressed genes encode proteins with no obvious similarity to known functional domains. Of particular interest is a member of the juvenile hormone-binding protein family, which was highly induced by both injury and microbial challenges. The possible role of juvenile hormone in innate immunity is discussed.

Ecdysone Titer Determined by 3DE-3β-Reductase Enhances the Immune Response in the Silkworm

“…This indicated that ecdysone could efficiently influence the immune system of the silkworm. Similar to other insects, silkworm also contains Toll and IMD signaling pathways to stimulate the expressions of different AMP genes, such as cecropin, gloverin, and moricin, although it is still unclear which AMPs are specifically regulated by which pathway (many AMPs can be upregulated by both positive and negative bacteria) (39)(40)(41). To assess the effect of 20E on silkworm innate immunity, we surveyed the transcriptional responses of several immune-related genes, including AMP genes (Gloverin and Morcin), adaptor of the Toll receptor (Myd88), peptidoglycan recognition protein (PGRP-S6), and cellular immune-related gene (C-type lectin).…”

Differential gene expression in silkworm in response to Beauveria bassiana infection

“…This highly diverse taxonomic group of insects encompasses some of the world's most destructive pests in agriculture, as well as many beneficial insects. B. mori, a model system for Lepidoptera, has contributed enormously to the study of Lepidopteran genetics and immunology (Goldsmith et al, 2005;Li et al, 2005Li et al, , 2007Liu et al, 2009;Wu et al, 2010). B. bassiana is one of the major fungal pathogens for silkworms and causes enormous damages to the sericultural industry.…”

Changes in the proteomes of the hemocytes and fat bodies of the flesh fly Sarcophaga bullata larvae after infection by Escherichia coli

“…Further studies on the immune systems of other insect species, such as Lepidoptera , contributed to our understanding of the processes and uncovered the differences in their host defense strategies [8,9]. …”