Figure 5.

JNK pathway mutations block antimicrobial peptide gene expression in larval fat body tissue. Mosaic bsk², msn¹⁷², and jun¹ mutant larval fat body clones were each generated individually and analyzed as described (see Materials and methods). Nuclear Hoechst staining is in blue. Mutant clonal tissue is marked by the absence of GFP in green. Genotypes are noted in the lower right of three-color panels. (A) diptericin expression (red) is absent in bsk² clones (all clones analyzed, >15, showed the same effect). (A′) diptericin expression shown in single channel. (B) Metchnikowin is lost in bsk² mutant clones (16 clones analyzed, all showing the same effect) and (C) drosomycin expression (red) is lost in bsk² mutant clones (again all out of 10 clones analyzed). (D) diptericin expression (red) is absent in msn¹⁷² clones (all of five clones analyzed, out of over 300 dissected larvae). Note in this example how the two mutant cells seem to be excluded from the fat body (red arrows). (E) attacin (red) and (F) drosomycin expression (red) is reduced in dJun¹ mutant cells (two clones analyzed). (G) rp49 expression (red) is unimpaired in bsk² mutant clones (seven clones analyzed). (H) dSTAT protein expression is normal in naïve bsk² mutant clones. (I) dSTAT protein is nuclear in infected bsk² mutant fat body cells (red arrows in (I′), five clones analyzed). Red channels are shown in (B′, C′, D′, E′, F′, G′, H′, I′).