Figure 4.

ARF1 and Asrij differentially regulate the Imd pathway. (A,B) Quantification of Imd pathway-governed antimicrobial peptide expression by qRT-PCR analysis shows that Attacin, Drosocin and Diptericin are highly up-regulated whereas Cecropin levels are unaffected in e33cGal4-mediated ARF1 knockdown flies (A). Cecropin levels are upregulated and Attacin, Drosocin, Diptericin levels are down-regulated in e33cGal4-mediated Asrij knockdown flies (B). (C–J) Quantification of the total percentile of flies expressing the Imd pathway reporters - Attacin-GFP, Cecropin-GFP, Drosocin-GFP and Diptericin-GFP in flies with e33cGal4 mediated ARF1 knockdown (C–F) or asrij knockdown (G–J) respectively. (K) Images showing unchanged intensity of Relish in the nucleus of arj9/arj9 larval fat body but increase in the intensity in arf1 knockdown larval fat body compared to the respective controls. Scale bar 10 µm. (L) Quantification of Relish intensity over the entire area of the tissue in the field of view as well as in the nucleus (DAPI stained area) in arj9/arj9 and arf1 knockdown fat bodies and in the respective controls (n = 10). Error bar represents standard error of mean. ns indicates statistically non-significant difference. * and ** indicates P-value < 0.05 and <0.01 respectively. (M) Model indicating the suggested role of the ARF1-Asrij endocytic axis in regulating the Imd pathway.