A DNA origami platform for quantifying protein copy number in super-resolution

Area of Science:

• Biophysics
• Cell Biology
• Microscopy

Background:

• Super-resolution microscopy enables nanoscale protein quantification.
• Calibration standards exist for fluorescent proteins but not for immunofluorescence with small organic fluorophores.

Purpose of the Study:

• To develop a calibration tool for quantifying protein copy number using immunofluorescence and super-resolution microscopy.
• To adapt DNA origami for calibrating labeling efficiency with small organic fluorophores.

Main Methods:

• Utilized DNA origami structures as a calibration platform.
• Combined DNA origami with antibodies targeting Green Fluorescent Protein (GFP).
• Employed single-molecule-based super-resolution microscopy techniques.

Main Results:

• Demonstrated DNA origami as a versatile platform for calibration.
• Successfully calibrated fluorophore and antibody labeling efficiency.
• Enabled accurate protein copy number quantification in cellular contexts.

Conclusions:

• DNA origami provides a novel solution for calibrating immunofluorescence in super-resolution microscopy.
• This method enhances the accuracy of protein copy number measurements.
• Facilitates quantitative analysis of protein expression at the nanoscale.