Red Fluorescence Spectrum From Soviet
Despite years of effort since its cloning in 1992, the GFP of the jellyfish Aequorea victoria (the most known and used green fluorescent reporter) has not been turned red... until now.
A team of Russian researchers started from a blueshifted GFP variant and performed a molecular mutagenesis evolution approach to get, not only shift toward red, but also some clues to the chromophore formation theory. Basically they made libraries of millions of mutants and sent them through a Dako cell sorter to select the best red performances that were mutated once again and analyzed iteratively until they achieved the desired shift to the red fluorescence. The results was a protein, R10-3, that has both red and green fluorescence, so a pure red protein has not derived yet (but the evolutive job is still in progress).
It is not the first time that a Russian team turns to red fluorescent reporters: some months ago we were reading the Nature Methods paper about Katushka and mKate. Is a matter of fact that red color is an innate hue in some countries: are there the basis to make a social association study about scientists, countries and reporter colors?
- Mishin, A.S., Subach, F.V., Yampolsky, I.V., King, W., Lukyanov, K.A., Verkhusha, V.V. (2008). The First Mutant of the Aequorea victoria Green Fluorescent Protein That Forms a Red Chromophore. Biochemistry, 47(16), 4666-4673. DOI: 10.1021/bi702130s