FIGURE 4

FIGURE 4

Smc5 deficiency activates tp53‐related apoptosis pathway in zebrafish. (A) Volcano plot showing common differentially expressed genes (DEGs) of HOM and wild‐type (WT) 3‐dpf embryos. The horizontal line indicates a log10 (adjusted p value) of 1.3 (Qvalue of .05); and the vertical lines a log2 fold change of −.58 and .58. (B) Top 20 enriched KEGG pathway and gene ontology (GO) biological process (ranked by p.adjust) from DEGs as in (A) using the ClusterProfiler R package. (C) The expression of genes involved in the DNA damage response and signal transduction by tp53 detected in 3‐dpf larvae by quantitative real‐time PCR (qPCR). Actin was chosen as the internal reference gene. (D) Knockdown of tp53 partially rescued the short phenotype in smc5^−/− larvae. WT, n = 77; smc5^−/−, n = 36; smc5^−/− + Ctrl morpholino (MO), n = 26; smc5^−/− + tp53 MO, n = 31; (E) body length of smc5^−/− embryos at 5‐dpf treated with 10‐μM C3742 from 3.5 to 4.5 dpf or indicated concentration of PFT‐α from 24 hpf to 5 dpf. WT, n = 38; smc5^−/−, n = 38; C3742 (10 μM) + smc5^−/−, n = 46; PFT‐α (1 μM) + smc5^−/−, n = 9; PFT‐α (2 μM) + smc5^−/−, n = 46; (F) deletion of tp53 in smc5 knockout (KO) zebrafish rescued the reduced body length. tp53^+/+, smc5^+/+, n = 9; tp53^+/+, smc5^−/−, n = 6; tp53^−/−, smc5^−/−, n = 9. In parts (C–F), values represent the mean ± s.e.m. *p < .05, **p < .01, ***p < .001