RIPK2

Class

RIPK2 scaffolding inhibitor

RIPK2 (receptor-interacting protein kinase 2) is an intracellular signaling protein that relays alarm signals from two sensors, NOD1 and NOD2, which detect fragments of bacterial cell walls inside cells. When these sensors are triggered, they recruit RIPK2, which then organizes a molecular platform that activates the transcription factor NF-κB and related pathways, driving production of inflammatory messengers. This pathway is a normal part of defense against bacteria, but when it becomes chronically overactive it contributes to inflammatory bowel disease, including Crohn's disease, and to rare autoinflammatory conditions such as Blau syndrome and sarcoidosis-like granulomatous disease, many of which are linked to mutations in NOD2 itself. RIPK2 has two functional roles: an enzymatic (kinase) activity and a separate scaffolding role, in which the protein itself, once modified by ubiquitin tags, serves as a docking platform for downstream signaling components regardless of its enzymatic activity. Because blocking the kinase alone does not always stop the scaffold from working, inhibitors designed specifically to disrupt the scaffolding function aim to shut down signaling more completely. This approach is being explored as a way to dampen chronic gut and systemic inflammation driven by this pathway.