Reporter

Part:BBa_K4245000

Designed by: Pablo Fernandez-Millan, Alexis Autour, Eric Ennifar, Eric Westhof, Michael Ryckelynck   Group: iGEM22_Lambert_GA   (2022-08-17)


iSpinach-D5-G30-A32 Aptamer

iSpinach-D5-G30-A32 is a co-crystallized, re-engineered version of iSpinach (BBa_K3380150) developed by researchers at the University of Strasbourg. They first re-engineered the original Spinach aptamer (BBa_K734002) to enhance fluorescence production and promote intermolecular interactions during crystallization. However, further research identified that with few mutations in the basal stem and UNCG loop, iSpinach-D5-G30-A32 optimizes iSpinach’s production and crystallization, improving its folding capacity (Millan et. al, 2017). iSpinach-D5-G30-A32 is a fluorescent light-up aptamers (FLAP) that binds to 3’5-difluoro-4-hydroxybenzylidene imidazolinone (DFHBI), a small dye derived from the GFP fluorophore, to produce fluorescence (Paige et al., 2011). As shown in Figure 1, the aptamer and DFHBI bind together to produce green fluorescence, which has roughly 50% of the fluorescence intensity of enhanced GFP (Neubacher & Hennig, 2018). However, FLAPs can be more effective than GFP in biosensing since they bind to a fluorophore after transcription (RNA), while GFP requires additional translation for expression. Similar to other FLAPs, iSpinach-D5-G30-A32 is expressed within a transfer RNA (tRNA) scaffold, which shields the RNA from misfolding and degradation (Paige et al., 2011).


Characterization-figure-3.png

Figure 1. DFHBI and iSpinach-D5-G30-A32 aptamer binding to form RNA-fluorophore complex.


Sequence and Features


Assembly Compatibility:
  • 10
    COMPATIBLE WITH RFC[10]
  • 12
    COMPATIBLE WITH RFC[12]
  • 21
    COMPATIBLE WITH RFC[21]
  • 23
    COMPATIBLE WITH RFC[23]
  • 25
    COMPATIBLE WITH RFC[25]
  • 1000
    COMPATIBLE WITH RFC[1000]


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