On the other hand, while chronic ERK1/2-signaling alone, similar to its serine/threonine protein kinase family members JNK and p38, may exert pro-apoptotic effects in some instances, for example during PD (Kulich and Chu, 2001; Gomez-Santos et al., 2002), ERK1/2 induces CREB-driven plasticity and survival gene expression (Hermann et al., 2000; Rai et al., 2019; Hölscher, 2020). This evidence concerns the gene MAPK8 and Parkinson disease.