A genetically encodable protein that emits fluorescence after appropriate excitation. Fusion constructs can label cellular structures, but expression and illumination must be controlled for effects on the process being observed.
GFP is a fluorescent protein used to report cellular location or gene expression. Fluorophore maturation and protein turnover introduce delays and filtering, so measured intensity does not in general reproduce an instantaneous transcription rate.
A fluorescent protein whose emission can be changed by controlled illumination. Conversion of one imaged progenitor enables independent spatial lineage tracing, limited by dilution, turnover and inadvertent conversion of neighbouring cells.
