TRAF6 and TRAF2/5 signaling pathways. (a) The endogenous TRAF6 and TRAF2/5 signaling pathways and post-translational modifications. (b) The presence of the psoriatic arthritis-associated single-nucleotide polymorphism (SNP) (rs33980500) could affect the proteins downstream of Act1. The decrease in TRAF6 binding could result in an increase in the TRAF2/5 signaling pathway and this in turn may lead to increased CXCL1 mRNA and protein expression. Act1, nuclear factor-kappa-B activator 1; ASF, alternative splicing factor; IKK, IkB kinase; IL-17, interleukin-17; IL-17R, interleukin-17 receptor; NF-κB, nuclear factor-kappa-B; TAB, transforming growth factor-beta-activated kinase 1 (TAK1)-binding protein; TAK1, transforming growth factor-beta-activated kinase 1; TRAF6, tumor necrosis factor receptor-associated factor 6.