In vitro selection of dye-fluorescence-enhancing peptide aptamer by cDNA display.

Area of Science:

• Biotechnology
• Molecular Biology
• Biochemistry

Background:

• Green Fluorescent Protein (GFP) is widely used but has limitations like steric hindrance and slow chromophore formation.
• Developing smaller fluorescent peptides with reduced molecular weight is challenging.
• Alternative methods using non-fluorescent dyes and peptides are being explored for improved cell imaging.

Purpose of the Study:

• To select a novel peptide aptamer capable of enhancing the fluorescence of non-fluorescent dyes.
• To overcome the limitations associated with Green Fluorescent Protein (GFP) in molecular imaging.
• To develop a new peptide-dye system for advanced cell imaging applications.

Main Methods:

• Selection of a dye-fluorescence-enhancing peptide aptamer using the cDNA display method.
• Confirmation of the selected peptide aptamer's function using the yeast surface display method.
• Investigation of the peptide aptamer's mechanism, involving binding to QSY®9 and inhibiting benzene sulfone group rotation.

Main Results:

• A novel peptide aptamer was successfully selected and confirmed.
• The peptide aptamer binds to the non-fluorescent dye QSY®9.
• Binding of the peptide aptamer enhances QSY®9 fluorescence by restricting molecular rotation.

Conclusions:

• The developed peptide aptamer effectively enhances the fluorescence of a non-fluorescent dye.
• This peptide-dye system provides a potential alternative to traditional fluorescent proteins for cell imaging.
• The findings enable the development of novel cell imaging techniques utilizing non-fluorescent dyes and peptide aptamers.