Fig 4. Rel-mediated inhibition of the JNK-FAO axis is essential for progenitor maintenance.

(A-B) Increase in whd transcripts level upon progenitor-specific Rel downregulation (A) (N = 3, P-values: = 0.0121, whereas overexpression (B) caused a decrease in whd level (N = 3, P-value: = 0.0101). The RNA was obtained from FACS-sorted progenitors via GFP expression using tepIV-GAL4>UAS-2XEGFP. (C-F) Compared to control (C), downregulating FAO using whd null allele (whd1) in Rel loss genetic background rescues the excessive differentiation (F), which was otherwise observed in Rel loss from progenitors (D). Downregulating FAO alone results in a halt in progenitor differentiation (E). (G) Differentiation index for genotypes C-F (lymph glands n = 10 for each genotype, P-values from left to right <0.001, <0.001, <0.001 and = 0.979 respectively). (H) The ratio of the area of progenitors to that of the total area of the primary lobe for the genotypes mentioned in C-F (lymph gland n = 10 for each genotype, P-values = <0.001, <0.001, <0.001 and = 0.147 respectively). (I-L) Blocking FAO by mildronate-supplementation in both control (J) and progenitor-specific Rel loss background (L) leads to a decline in differentiation, which is otherwise significantly increased upon progenitor-specific Rel loss (K) compared to unfed control (I). (M) Differentiation index for genotypes I-L (lymph glands n≥10 for each genotype, P-values from left to right <0.001, <0.001 and <0.001, respectively). Genotypes are as mentioned. Each dot in the graph represents individual values, Data represented as mean±SD. Statistical analysis: Unpaired t-test with Welch’s correction for qPCR and rest Tukey’s multiple comparisons tests. P-Value of <0.05, <0.01 and<0.001, mentioned as *, **, *** respectively. Scale bar: 20μ, DAPI: nucleus.