NPR-C Protects Embryonic Stem Cells from Apoptosis by Regulating p53 Levels

The identification of intrinsic factors required for propagation of self-renewing embryonic stem (ES) cells is important to improve the efficiency of expansion of ES cells for therapeutic purposes. Here, we report a novel role for natriuretic peptide receptor-C (NPR-C) in the survival of murine ES cells. We found that NPR-C was highly expressed in ES cells and was downregulated during ES cell differentiation. Knockdown of NPR-C in ES cells by using a small-interfering RNA resulted in apoptotic cell death, and the induction of p53 protein expression. Conversely, chemical inhibition of p53 by alpha-pifithrin significantly reduced apoptosis in NPR-C-deficient cells. cANF((4-23)), a selective NPR-C agonist, protected ES cells against oxidative stress-induced apoptosis, and blocked activation of p53 and Nanog suppression in the presence of DNA-damaging agents. Thus, NPR-C is required to control DNA damage-induced p53 levels to maintain ES cell self-renewal.