Fig. 4

Intestinal microorganisms are not required for PIK3C3 deficiency-induced inflammation. a Scatter plots showing the qRT-PCR results of the indicated genes in 8 dpf embryos under either standard or germ-free culture conditions. Each dot represents the mean of three technical replicates from one embryo. Inflammatory genes are significantly stimulated in mutants under germ-free culture condition. NS, non-significant; *p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001 in one-way ANOVA with Tukey’s multiple comparison. b Neutrophils accumulate in the digestive tract of mutant in the absence of gut microbiota. Images were acquired as described in Fig. 3c. c Scatter plot showing the numbers of bacteria in intestinal homogenates from individual embryo at 6, 7, and 8 dpf under standard culture condition. WT and mutants have similar gut bacteria at 6 and 7 dpf. However, the number of gut bacteria becomes either very low (<20 CFU/gut, 5 out of 14 embryos) or undetectable (9 out of 14) in the mutants at 8 dpf, which is significantly reduced when compared to that in wild type siblings (NS, non-significant; ***p < 0.001 in one-way ANOVA with Tukey’s multiple comparison)