MAPK8 and psoriasis: In psoriasis, nuclear translocation of NF-κB and transcription of NF-κB target genes, such as AP-1 and C/EBPs, are increased.239 In addition to activating the NF-κB pathway, the signals can also activate the MAPK pathway (including JNK, ERK, and p38), and the released MAPKs phosphorylate and activate AP1.240 Of note, IL-17RA/RC can also recruit other signaling molecules, such as TRAF2 and TRAF5.