Alpha-kinase 1 (ALPK1) (ALPK1)

Alpha-kinase 1 (ALPK1) is a cytosolic pattern recognition receptor that serves as a critical sensor for the bacterial metabolite ADP-heptose, an intermediate in the biosynthesis of lipopolysaccharide [PubMed: 30111836]. Upon binding ADP-heptose, ALPK1 undergoes activation and phosphorylates the adapter protein TIFA, which subsequently triggers the assembly of TIFAsomes and the activation of the NF-kappaB signaling pathway to induce pro-inflammatory cytokine production [UniProt: Q96QP1]. The T237M variant is a specific gain-of-function mutation located in the N-terminal alpha-helical domain of ALPK1, which leads to constitutive, ligand-independent kinase activity [PubMed: 31819146]. This mutation is the primary genetic cause of ROSAH syndrome, a rare autosomal dominant autoinflammatory disease characterized by retinal dystrophy, optic nerve edema, splenomegaly, anhidrosis, and chronic headaches [PubMed: 31819146]. The T237M mutation resides in the N-terminal domain and promotes a conformational change that mimics the ligand-bound state, resulting in chronic signaling and systemic inflammation. Because the T237M variant drives the chronic inflammatory state and progressive ocular damage in ROSAH patients, ALPK1 has emerged as a significant therapeutic target for small molecule inhibition. Currently, there are no FDA-approved drugs that specifically target ALPK1, although experimental inhibitors like VENT-03 are being explored to treat ROSAH syndrome and other inflammatory conditions associated with the ALPK1-TIFA axis. Inhibition of this pathway is expected to alleviate both the systemic inflammatory symptoms and the progressive vision loss associated with the disorder.

Other names

Alpha-protein kinase 1LAKLymphocyte alpha-kinaseC4orf7Chromosome 4 open reading frame 7

ALPK1 inhibitors function by binding to the kinase domain or allosteric sites of Alpha-kinase 1 to prevent the phosphorylation of the adapter protein TIFA. This blockade inhibits the formation of TIFAsomes and the subsequent activation of the NF-kappaB pathway, thereby reducing the production of pro-inflammatory cytokines such as IL-1β and TNF-α [PubMed: 31819146, 30111836].