Differential regulation of JAK/STAT-signaling in patients with ulcerative colitis and Crohn’s disease

Figure 1 The JAK/STAT pathway. A: Canonical Janus kinase (JAK)/signal transducer and activator of transcription (STAT)-signaling initiates with the association of cytokines and their corresponding transmembrane receptors; B: Cytokine binding brings JAKs in proximity to the receptor, leading to phosphorylation of both the JAKs themselves and the cytoplasmic tails of the receptors, thereby creating docking sites for STAT monomers; C: STAT tyrosine phosphorylation (p-Tyr) is the major activating event, leading to dimerization of STATs, translocation to the nucleus, DNA binding of STAT dimers and subsequent target gene induction. JAK: Janus kinase; STAT: Signal transducer and activator of transcription.