STING R224 variant (human, recombinant)

STING R224 variant (human, recombinant) contains amino acids 138-379 of the wild-type variant (R232) with lysine 224 substituted with arginine. Stimulator of interferon genes (STING) is a component of the innate immune response that binds to cyclic dinucleotides, which are bacterial second messengers, leading to activation of NF-κB and transcription of immunomodulatory genes, including type I interferon (IFN). The R232 variant of STING is the most common variant in the human population, found at a frequency of 57.9% in the 1000 Genome Project. The SNP variant H232 is found at a 13.7% frequency. The K224R mutation prevents ubiquitination of STING at position K224, a process which is essential for efficient cytosolic DNA-mediated signaling. Therefore, this mutation disrupts optimal STING trafficking, which inhibits TBK1-mediated IRF3 activation but not NF-κB activation.