Markéta Procházková, 175241 Poster for presentation
Doctoral conference XD107 on June 9, 2022
1
Poster title:
Bioluminiscence probe for caspase imaging inside cells based on
Förster resonance energy transfer
Abstract
Nowadays, luminescent semiconductor quantum dots (QDs) are widely applied in different
areas due to their unique optical properties. Modern technologies and instrumentations of laserinduced
fluorescence or bioluminescence offer the possibility to study biological phenomena at
a cellular or even molecular level.
Our research is focused on biologically active molecules, such as caspases, which play
important roles in cell signaling regulation in normal and diseased states and are attractive
targets for biological diagnosis and also for medical therapy.
In this work, synthesis and testing of a novel quantum dot luminescent probe is presented. The
synthesized luminescent probe was tested by a model reaction with active human recombinant
caspase-3 protein in quartz cuvette of a fluorimeter and its luminescence properties were
checked by monitoring of the reaction inside the MC3T3-E1 cells treated with camptothecin.
The caspase enzyme reaction is based on the specific cleavage of the DEVD peptide sequence.
Thus, the BHQ-2 quencher is released, the Förster resonance transfer between quantum dot and
quencher is interrupted, and consequently the red light luminescence of the quantum dot is
emitted (Figure 1).
Figure 1: Scheme of the quantum dot FRET-based luminescent probe reaction with cleaving enzyme.
Markéta Procházková, 175241 Poster for presentation
Doctoral conference XD107 on June 9, 2022
2
Thus, due to the high stability, the synthetized QD FRET-based luminescent probe proved to
enable much longer observation of active caspases in living cells under fluorescence
microscope than commercially available probes. The luminescence properties of the novel
quantum dot luminescent probe were checked by monitoring of the reaction inside the MC3T3E1
cells treated with camptothecin (Figure 2).
Figure 2 Comparison of the white light microscope picture (in the left) and the fluorescence microscope
picture (in the right) of the MC3T3-E1cells treated with camptothecin 24 hours after incubation with
fluorescent probe.
Acknowledgement
The work has been supported by the Grant Agency of the Czech Republic, project no. GA20-00726S.