Abstract
Except for hemocytes and fat bodies, insect immune tissues have not been carefully determined. To identify the organs that express cecropin B in silkworms, we constructed a transgenic silkworm that was transformed with the green fluorescent protein (GFP) gene under the control of an 800-bp CecB2 promoter region and followed by the 540-bp 3'-UTR of CecB2 using a transposon, piggyBac. In the transgenic silkworms, little GFP was detected in normal larvae, while a strong GFP signal was observed in the fatbodies, hemocytes, and tracheae in the head and testis after bacteria injection. Our finding that infection induces an antibacterial peptide in generative cells in insects is new.
