Phenotype of mutants for housekeeping genes are similar and depend on p53 network upregulation.

A–C) Excessive neural apoptosis was manifested as gray areas in the brain at 24 hpf, which was rescued by p53 inhibition D–F) At 48 hpf, there were more apoptotic cells in mutants compared to siblings and p53 inhibition led to a decrease in apoptosis. Acridine orange staining. G–I) There were fewer erythroid cells in mutants compared to siblings, which was rescued by p53 inhibition. o-dianizidine staining, 84 hpf, arrow points to erythrocytes. K–L) tp53 upregulation was higher in the brain and blood cells, 48 hpf, in situ hybridization, arrow points to erythrocytes.

In mutants, biosynthesis was generally suppressed and catabolism was activated.>

A) Expression of structural proteins was downregulated; tuba2 is shown as an example. B) Expression of catabolizing enzymes was upregulated; mmp9 is shown as an example. C) Expression of neural genes was especially strongly suppressed in mutants; nrd is an example of a downregulated neural gene. D) Expression of a neural crest cell marker tfap2 was downregulated. E) Only rudiments of the head skeleton derived from neural crest cells were present in the mutants. Alcian blue. Day 4. F) Upregulation of p53 affects blood development; HSC marker runx1 was downregulated in the mutants; u2af1 mutant is shown as an example.