Smallest near-infrared fluorescent protein evolved from cyanobacteriochrome as versatile tag for spectral multiplexing.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 30655515.
- Also identified by DOI 10.1038/s41467-018-08050-8 and PMC identifier 6336887.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
From a single domain of cyanobacteriochrome (CBCR) we developed a near-infrared (NIR) fluorescent protein (FP), termed miRFP670nano, with excitation at 645 nm and emission at 670 nm. This is the first CBCR-derived NIR FP evolved to efficiently bind endogenous biliverdin chromophore and brightly fluoresce in mammalian cells. miRFP670nano is a monomer with molecular weight of 17 kDa that is 2-fold smaller than bacterial phytochrome (BphP)-based NIR FPs and 1.6-fold smaller than GFP-like FPs. Crystal structure of the CBCR-based NIR FP with biliverdin reveals a molecular basis of its spectral and biochemical properties. Unlike BphP-derived NIR FPs, miRFP670nano is highly stable to denaturation and degradation and can be used as an internal protein tag. miRFP670nano is an effective FRET donor for red-shifted NIR FPs, enabling engineering NIR FRET biosensors spectrally compatible with GFP-like FPs and blue-green optogenetic tools. miRFP670nano unlocks a new source of diverse CBCR templates for NIR FPs.
Medical subject headings
- Bacterial Proteins
- Biosensing Techniques
- Cyanobacteria
- Luminescent Proteins
- Photoreceptors, Microbial