Difference between revisions of "Part:BBa K3380150"

Revision as of 12:19, 8 October 2020

iSpinach fluorescent RNA aptamer

iSpinach is a fluorescent RNA aptamer comprising a short ribonucleotide sequence that exhibits fluorescence upon binding to a specific fluorophore.

Characterization

The iSpinach fluorescent RNA aptamer is derived from the Spinach2 sequence described by [http://www.nature.com/nmeth/journal/v10/n12/full/nmeth.2701.html Strack et al. (2013)].

The iSpinach folding prediction as simulated by [http://www.nupack.org// NUPACK] is shown below.

Usage and Biology

It is usually used in live-cell imaging, however it can also be used in vitro. ISpinach can be used for visualisation by gene fusion to the target of interest. Its fluorescent colour is green. Some of the most commonly used fluorophores are DFHBI ((Z)-4-(3,5-Difluoro-4-hydroxybenzylidene)-1,2-dimethyl-1H-imidazol-5(4H)-one) and DFHBI-1T ((Z)-4-(3,5-difluoro-4-hydroxybenzylidene)-2-methyl-1-(2,2,2-trifluoroethyl)-1H-imidazol-5(4H)-one. The emission spectra depends on the bound fluorophore. The DFHBIfluorophore has an excitation wavelength of 492 (nm) and an emission wavelength of 516 (nm).

Its short length allows it to be synthesized rather than being cloned using plasmids. To increase its stability and increase its folding the iSpinach can be transcribed using tRNA scaffolds such as F30 (BBa_K3380101 and BBa_K3380102). The tRNA scaffolds increases its fluorescence.

Sequence and Features