Prolonged activation of il1b expression in the clo mutant after fin fold amputation.
(A) Transcriptome analysis of posterior fin fold tissues from uncut WT, amputated WT, and amputated clo mutant at 6 hpa. The ordinate, final RPKM, indicates the reads per kilobase of exon model per million mapped reads. Expression of regeneration-induced genes such as fn1b, junba, junbb, mmp9, and fgf20a was upregulated in the clo mutant. Notably, expression of inflammation-related genes such as il1b, tnf1b, and ptgs2a was highly upregulated in the amputated clo mutant. (B) RT-PCR analysis of il1b expression in WT and clo larvae at 3, 6, and 12 hpa. actb1: actinb1. (C) ISH analysis of il1b expression at corresponding stages of regeneration in WT and clo. Arrowheads indicate myeloid-like cells expressing il1b. Scale bars, 25 μm. (D) Quantification of il1b expression. The level of il1b expression was divided into four groups according to the ISH signal; the numbers in the bars indicate the ratios of the respective groups. Data are the sum of three experiments (total n > 13 for each sample). The data suggest that il1b expression extended into later stages in clo than in WT. (E) ISH analysis of il1b expression after LPS injection. Phenol red: negative control containing only phenol red; hpi: hours post injection. Scale bars, 200 μm.