By Our Correspondent
April 8 - Researchers at the School of Animal Science, South China Agricultural University, in collaboration with partners, have made a series of significant advancements in the field of silkworm antiviral immunity research, funded by projects such as the National Natural Science Foundation and the Natural Science Foundation of Guangdong Province. The relevant findings have been successively published in journals including Insect Biochemistry and Molecular Biology, Innate Immunity, and Insect Science.
The midgut serves as a crucial barrier against microbial invasion and is the primary target tissue when baculoviruses invade hosts. However, the immune responses of different midgut cell types to viral infection remain unclear. For the first time, the research team constructed a map of silkworm larval midgut cells. Further experiments revealed the immune evasion strategies of BmNPV virus infection in the midgut late stage, including: inhibition of host antiviral pathways' response, suppression of antiviral host factor expression, and activation/promotion of gene expression for BmNPV virus replication. This study unveiled the diversity of silkworm larval midgut cells and revealed the interplay between host and viral infection at the single-cell level. The relevant results were published in Insect Biochemistry and Molecular Biology.
For a long time, the brain has been considered an immune-privileged organ, but recent research has found that both vertebrate and invertebrate central nervous systems can trigger immune responses. To explore the diversity of silkworm brain cell types and how different cell subgroups respond to viral infection, the research team constructed, for the first time, a map of silkworm larval brain cells under both BmNPV virus-infected and uninfected states. It revealed that the cell subgroup primarily exerting antiviral functions in the silkworm larval brain is hemocytes. Further experiments elucidated that in the silkworm larval brain, BmNPV virus infection significantly induced the expression of antimicrobial peptides (especially lysozyme) in hemocytes, exerting antiviral effects through antiviral peptides. The relevant results were published in Innate Immunity.
To further explore the functions of discovered silkworm immune genes, the research team identified information on 427 immune-related genes in the latest publicly available silkworm genome data. Subsequently, these genes were categorized into different groups such as pattern recognition receptors, classical immune pathways, effector genes, and other immune-related genes. Moreover, the 427 silkworm immune-related genes were matched with publicly available whole-genome CRISPR screening library data to obtain potential silkworm antiviral immune-related genes. Subsequent antiviral experiments were conducted on selected immune genes to validate their functions. This achievement provides systematic information on silkworm immune-related genes and demonstrates their applications, serving as a convenient and reliable information source reference for silkworm immune research. The relevant results were published in Insect Science.
Related Paper Information: https://doi.org/10.1016/j.ibmb.2023.104043 https://doi.org/10.1159/000537815 https://doi.org/10.1111/1744-7917.13363
