Fig. 3. Transcriptomic analysis of early wound tissue reveals gene expression changes associated with regenerative outcomes.

(A) Tissue was collected from the amputation site from MDT and ND animals at 11 hpa, 24 hpa, and 7 dpa and subjected to RNA-seq analysis. (B) Heatmap comparing gene expression levels of MDT animals compared to ND shows significant differential gene expression at 11 hpa that persists to 24 hpa (see color-coded legend). At 7 dpa, however, dynamic gene expression levels return to normal, indicating a period of dynamic gene expression within 24 hours of amputation. Next, we compared the top 20 enriched (C) up-regulated and (D) down-regulated KEGG pathways in X. laevis treated with MDT versus ND overtime. (E and F) Gene set enrichment analysis (GSEA) revealed that inflammatory signaling and cell morphogenesis gene sets were up-regulated in blastema treated with CT at 11 hpa (left) and 24 hpa (middle) (G), which switched to more cellular regulation and metabolic mechanisms at 7 dpa (right). (H to J) We identified a handful of genes that were highly regulated in MDT blastema at 11 hpa (left), 24 hpa (middle), and 7 dpa (right)—particularly with MDT animals as compared to ND animals. Up-regulated genes included immune system–related transcripts (e.g., PTGS2, TGFB1, IL1B, and FOXP3), which suggest an important role of inflammation in pro-regenerative states.