Green Fluorescent Protein ( GFP )

Abstract

Green fluorescent protein (GFP), a fluorescent molecule, found in the jellyfish Aequorea victoria , was the first of a diverse family of fluorescent proteins cloned from marine invertebrates. Fluorescent proteins are useful reporter molecules for in vitro and whole organism gene expression studies and for tracking subcellular localisation of proteins in living cells. Because they fold robustly in nearly all biological systems studied and require no cofactors for development of fluorescence, fluorescent proteins have become ubiquitous tools in a broad range of cell biology subdisciplines. Colour variants covering the entire visible spectrum have been engineered from various wild‐type fluorescent proteins, allowing the simultaneous imaging of multiple proteins within the same cell, as well as advanced applications such as biochemical activity reporters. Additional engineering has produced variants that change colour upon illumination or whose fluorescence can be switched on and off, making them useful for other advanced imaging techniques. Key Concepts: The green fluorescent protein from Aequorea victoria was the first intrinsically fluorescent protein to be discovered. A diverse family of fluorescent proteins has been cloned from a wide variety of marine invertebrates including jellyfish, corals, copepods and lancelets. Fluorescent proteins are highly useful reporter genes in a wide variety of biological systems. Fluorescent proteins have been the subject of heavy engineering efforts to improve their physical and optical properties as genetically encoded tools. Colour variants of fluorescent proteins allow multicolour protein tracking in living cells. Advanced uses for fluorescent proteins include optical sensing of important signalling molecules such as calcium and biochemical activities such as kinase activation. Photoactivatable and photoswitchable fluorescent proteins can be used for ‘superresolution’ imaging of cellular structures below the optical diffraction limit.

The Benefits of Unnatural Amino Acid Incorporation as Protein Labels for Single Molecule Localization Microscopy

“…The structure of a FP consists of a β-sheet barrel that encloses a helix structure containing the central chromophore (Shaner, 2014 ). While FPs are generally resistant to denaturing, high temperatures and proteolysis, there is variability in the speed of chromophore maturation and in the aggregation of POI-FP fusions (Cranfill et al, 2016 ).…”