Fig. 5.

FBti0019386 is most likely the causal mutation for the differences in expression of Bin1 and for the increased tolerance to P. entomophila. A FBti0019386 harbors two immune-related TFBSs, Caudal and DEAF-1, that are responsible for the enhancer activity of this insertion in infected conditions. Schematic representation of the vector construction with the promoter region of Bin1 without FBti0019386 sequence, with FBti0019386 (represented in red), and with the FBti0019386 sequence without the immune-related binding sites for Caudal and DEAF-1 (represented in yellow) cloned upstream of the reporter gene Gfp. Below, normalized expression levels of the reporter gene in transgenic female guts with the different constructions are shown. B FBti0019386 adds a new TSS to its nearby gene Bin1 used under infected conditions. On the left, we represented all the transcripts annotated for Bin1. On the right, we show the different Bin1 transcripts found in non-infected and infected conditions in flies with and without FBti0019386. UTR regions are depicted in light grey while coding regions are depicted in dark grey. TE-overlapping regions are represented in red. Transcript regions wave-patterned are inferred from FlyBase transcript annotation and were not sequenced in this work. Bin1-RD and Bin1-RE transcripts are, respectively, 318 bp and 172 bp shorter compared to Bin1-RC transcript. C Normalized Bin1 expression levels from female guts in the two backgrounds analyzed in the ASE experiments, and in a third homozygous background with FBti0019386 insertion (IT_Cas 11_49-5, an isofemale strain) in both non-infected and infected conditions. Error bars represent SEM. ND: not detected. D Normalized Bin1 expression levels from female guts in outbred populations without (grey) and with FBti0019386 insertion (red), and in the two CRISPR-mutants FBti0019386-A1 (light blue) and FBti0019386-A2 (dark blue) in both non-infected and infected conditions. E Survival curves in non-infected (discontinuous lines) and infected conditions (continuous lines) for outbred flies with FBti0019386 insertion (red) and without this insertion (grey), and in the two CRISPR-mutants FBti0019386-A1 (light blue) and FBti0019386-A2 (dark blue). Error bars represent SEM