Fig. 4

Atf4a deficiency disrupts energy metabolism in zebrafish. (A) Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of differentially abundant metabolites in wt and atf4a−/− zebrafish embryos treated with normoxia or hypoxia at 72 hpf. The X-axis represents the enrichment ratio, and color indicates the p-value. Yellow boxes highlight pathways with p < 0.05. (B–F) Relative abundance of key tricarboxylic acid (TCA) cycle metabolites, including pyruvate, succinate, fumarate, malate, and oxoglutarate in wt and atf4a−/− embryos treated with normoxia or hypoxia at 72 hpf. (G) Viability of wt and atf4a−/− embryos under hypoxic conditions, with or without 10 μg/mL malate or α-KG supplementation. Data are presented as mean ± SEM from three independent experiments. Statistical significance was determined by unpaired two-tailed Student's t-test. ns, not significant. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001.