Single molecule FRET biosensor linker based on the principle of fluorescence resonance energy transfer

摘要

The present invention relates to a single molecule type based on the principle of fluorescence resonance energy transfer that enables non-invasive measurement of serine threonine kinase activity, tyrosine kinase activity, activity of low molecular weight GTP binding protein, and the like. It is an object of the present invention to provide a single molecule FRET biosensor including a FRET biosensor linker and a general linker. A polypeptide comprising 52 amino acid residues or more and 400 amino acid residues or less, wherein at least 95% of the total number of amino acid residues consists of glycine, serine, threonine and alanine, glycine is 35 to 65%, serine And a single molecule type FRET biosensor comprising a linker containing 10 to 40% of at least one of threonine, 10 to 40% of alanine, and a general linker, and an expression vector containing a gene encoding the biosensor. Cells and transgenic non-human animals.