Cloning and expression of a gene encoding gallerimycin, a cysteine-rich antifungal peptide, from eri-silkworm, Samia cynthia ricini

A cDNA clone encoding gallerimycin was isolated from larval fat body of immunized Samia cynthia ricini and named as Scr-gallerimycin. In naive larvae, no gene expression was detected, but strongly induced in fat body and hemocytes following immune challenge with bacteria or entomopathogenic fungus Beauveria bassiana. Strong expression of the gene was also induced by injection of peptidoglycan and zymosan, but very weakly by non-pathogenic fungus Aspergillus oryzae. Analysis of the sequence upstream from the cDNA shows the presence of motifs homologous to binding sites for NF-κB, C/EBP and CRE-BP1.