We also used B. mori to analyze the AMPs expression after bacterial infection or NO donor treatment (Figure S6A), and found that NO donor NOC had strong activity to induce the expression of AMPs Cecropin D, Cecropin E, Lebocin, Moricin and Defensin A. Moreover, inhibition of NOS using L-NAME increased the death of bacterial infected B. mori larvae (Figure S6B), which was consistent with the survival assay using O. furnacalis larvae. This evidence concerns the gene NOS2 and bacterial infectious disease.