IMAGE

Fig. 5

ID
ZDB-IMAGE-231215-81
Genes
Source
Figures for Thompson et al., 2020
Image
Figure Caption

Fig. 5 A TREE linked to cx43 directs blastemal gene expression. (A) RNA-seq and ATAC-seq browser tracks indicating the cx43E24 TREE near the upregulated cx43 transcript in regenerating fibroblast and whole-fin tissue. Tracks represent normalized combined replicates. (B) The cx43E24-fos:EGFP enhancer reporter construct. The 945 bp candidate TREE (blue arrow) was placed upstream of a 96 bp c-fos minimal promoter (yellow arrow) to direct fluorescent EGFP expression (green arrow). (C) Larval cx43E24:EGFP animals at 5 days post fertilization (dpf) displaying EGFP expression in trunk muscle (mus) and early pectoral fins. High magnification view of a larval pectoral fin (arrowhead) (C′). Scale bars: 500 μm. (D) The three dorsal-most caudal fin rays in some strongly expressing cx43E24:EGFP animals express EGFP in uninjured tissue, although this is not present in all lines. Scale bar: 300 μm. (E-G′) Longitudinal sections indicate cx43 expression (violet) in fibroblasts (white asterisks) and joint osteoblasts in wild-type fish (E) and cx43E24Δ/Δ fish (F) by in situ hybridization. Expression in forming joints is marked by black arrowheads. cx43E24:EGFP reporter fish exhibit a similar EGFP immunofluorescence pattern to endogenous cx43, although EGFP expression is detected in most blastemal osteoblasts (white arrowheads) in addition to blastemal fibroblasts (white asterisk) (G,G′). Scale bars: 100 μm. (H-J) cx43E24:EGFP fish display mesenchymal EGFP expression by 4 dpa, fading by 21 dpa. Arrowheads indicate amputation plane. Scale bars: 300 μm. (K,L) qPCR analysis of cx43 transcript levels in cx43E24Δ/Δ and wild-type fins. Expression is induced at 4 dpa but to a lesser extent than in wild-type fins. Each biological replicate pool of three fins each was performed in technical triplicate, and paired two-tailed t-tests were performed to indicate significance (n=8). (M) Lengths of regenerating fins are similar in cx43E24Δ/Δ and wild-type fish (n=14). Paired two-tailed t-tests were performed to indicate significance. (N) Fin ray segment length at 7 dpa was decreased by 6.2% distal to the amputation plane and 5.2% shorter proximal to the amputation plane in regenerating cx43E24Δ/Δ fins compared with wild-type fins (n=14). Paired two-tailed t-tests were performed to indicate significance. Data are mean±s.d.

Figure Data
Acknowledgments
This image is the copyrighted work of the attributed author or publisher, and ZFIN has permission only to display this image to its users. Additional permissions should be obtained from the applicable author or publisher of the image. Full text @ Development