IL17A and colitis: Although TRAF5 (RNF84) promotes the ubiquitination and stabilisation of the retinoic acid-related orphan receptor γt that mediates proinflammatory Th17 cell differentiation and IL17A/IL17F expression [99, 100], TRAF5-deficient mice exhibit aggravated experimental colitis and upregulation of proinflammatory cytokines [101].