Red fluorescent proteins are useful as morphological markers in neurons, often complementing green fluorescent protein-based probes of neuronal activity. However, commonly used red fluorescent proteins show aggregation and toxicity in neurons or are dim. We report the engineering of a bright red fluorescent protein, Crimson, that enables long-term morphological labeling of neurons without aggregation or toxicity. Crimson is similar to mCherry and mKate2 in fluorescence spectra but is 100 and 28% greater in molecular brightness, respectively. We used a membrane-localized Crimson-CAAX to label thin neurites, dendritic spines and filopodia, enhancing detection of these small structures compared to cytosolic markers.
Keywords: RFP; crimson; label; long-term; neuron; non-aggregating; red fluorescent protein.
Copyright © 2022 Ning, Geng, Lovett-Barron, Niu, Deng, Wang, Ataie, Sens, Ng, Chen, Deisseroth, Lin and Chu.