Differential activation of the lectin and antimicrobial peptide genes in Sarcophaga peregrina (the flesh fly)

Sarcophaga lectin is an immune defense protein which is transcriptionally induced upon immune challenge in the flesh fly, Sarcophaga peregrina. So far, we have revealed that the Sarcophaga lectin gene has multiple NF-κB -binding motifs in its promoter. Here we showed that the nuclear extracts from Sarcophaga-derived culture cells, NIH-Sape-4, and larval fat bodies have binding activity to the multiple κB motifs in the lectin gene promoter, some of which were responsive to immune stimuli. We also compared the expression profiles of the lectin gene with those of the antibacterial peptide genes from the point of view of inducers, expression tissues and local induction in digestive tracts. In each case, the lectin gene was activated in different manners from other inducible defense genes. These results indicate the complex regulation of the lectin gene, possibly by NF-κB -related transcription factors. Arch. Insect Biochem. Physiol. 2008.