Figure 3.

p38 MAPKs pathway and its upstream and downstream activation. The four p38 MAPK family members (p38α, p38β, p38γ, and p38δ) are activated by external stress, inflammatory cytokines, or UV radiation, which is similar to the JNK pathway. Once activated, this pathway initiates production of the pro-apoptotic transcription factors for inflammation, differentiation, proliferation, apoptosis, senescence, and RNA splicing.