Rapid, biochemical tagging of cellular activity history in vivo.
bioRxiv : the preprint server for biology May 14, 2024 Run Zhang, Maribel Anguiano, Isak K Aarrestad et al. 5 citations preprint
A new enzyme-based method called CaST (Ca2+-activated Split-TurboID) biochemically tags cells with elevated calcium levels in living animals within 10 minutes, without requiring implants or light delivery. The signal increases with calcium concentration and labeling time, acting as a time-gated integrator of calcium activity. Unlike transcriptional reporters that take hours, CaST allows immediate read-out after activity labeling. The approach was used to tag prefrontal cortex neurons activated by psilocybin in untethered mice, and the CaST signal correlated with psilocybin-induced head-twitch responses.