Concretely, ERK1/2 inducible proteins Jun b proto-oncogene (JunB) mediates ERK1/2 activation via the AP-1 complex, which increases the expression of several Th2 cytokines and drives Th2 cell differentiation, causing childhood asthma (Alam and Gorska, 2011). Here, JUNB is linked to childhood onset asthma.