Overview
- Two independent papers report that STING responds to the membrane lipid PI(3,5)P2 in addition to the nucleotide messenger cGAMP.
- Cryo-electron microscopy from a separate lab confirms that PI(3,5)P2 binds STING.
- Cells unable to produce PI(3,5)P2 show suppressed STING signaling, demonstrating a functional role for the lipid.
- Researchers describe cGAMP as an on–off trigger and PI(3,5)P2 as a dimmer that modulates the strength of the inflammatory response.
- Experts note that PIKfyve is the sole kinase that generates PI(3,5)P2, and altering its activity also affects other phosphoinositides and cellular processes.