"Optogenetics" allow researchers to stimulate synaptic activity in specific neurons that are made to express light-sensitive ion channels (channelrhodopsins).
Despite the variety of opsins with different peak wavelength sensitivities, until now it has not been possible to independently activate two distinct neural populations without significant cross-talk or losing temporal resolution.
Researchers at MIT reported in Nature on two new opsins with non-overlapping excitation spectra, Chronos and Chrimson, that allow independent optical excitation of distinct neural populations in mouse brain slices. These tools open the door to explore how multiple synaptic pathways interact to encode information in the brain.

Opsin genes occur naturally in microbial algae. In order to efficiently express these genes in mammalian cells, these researchers turned to GenScript for codon optimization and gene synthesis. GenScript has developed the leading codon-optimization algorithm: OptimumGene, patented in 2012 and continuously improved based upon the latest research findings.