Tissue degeneration is accompanied by p53 induction with a puma acute response and sustained increase of cyclin G1 and cdkn1a expression.
A) Immunoblot analysis of p53 in 10-month old WT and tert-/- testes and gut lysates. 6 month-old WT zebrafish were injected with the DNA damaging agent doxorubicin to serve as positive control for p53 activation. Asterisk depicts a non-specific cross-reactive band that serves as loading control. RT-qPCR analysis showing expression of B) pro-apoptotic (puma) and cell cycle arrest targets (C) cyclin G1 and D) cdkn1a) in testes, head kidney, gut and muscle of 1, 3, 6 and c.12 months old WT and tert-/- zebrafish (N = 3 to 8 fish per genotype). Data are represented as mean +/- SEM. Rel. mRNA refers to relative mRNA levels of each gene normalized to beta-actin.