Composite

Part:BBa_K4245001

Designed by: Manasvi Gupta, Natalie Tan, Vandana Vijay Kumar, Christina Cho, Nick Lockhart, Hari Mudigonda, Janet Standeven   Group: iGEM22_Lambert_GA   (2022-08-17)
Revision as of 12:57, 10 October 2022 by Manasvigupta (Talk | contribs)


Spinach aptamer with LacI repression

This part produces the fluorescent RNA aptamer Spinach (BBa_K734002) under the control of IPTG. Originally generated by the Jaffrey Lab at Cornell University, the Spinach aptamer 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 assince they bind to a fluorophore after transcription (RNA), while GFP requires additional translation for expression. Similar to other FLAPs, Spinach 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 Spinach aptamer binding to form RNA-fluorophore complex.


The LacI protein represses the inducible promoter (BBa_R0010), which stops downstream transcription of the Spinach aptamer. When IPTG is present, LacI is inhibited, allowing for the transcription of the aptamer. Once DFHBI binds to the aptamer, the RNA-fluorophore complex produces a quantifiable green fluorescence.


Sequence and Features


Assembly Compatibility:
  • 10
    COMPATIBLE WITH RFC[10]
  • 12
    INCOMPATIBLE WITH RFC[12]
    Illegal NheI site found at 361
  • 21
    COMPATIBLE WITH RFC[21]
  • 23
    COMPATIBLE WITH RFC[23]
  • 25
    COMPATIBLE WITH RFC[25]
  • 1000
    COMPATIBLE WITH RFC[1000]


[edit]
Categories
Parameters
None