Quantification of a Neurological Protein in a Single Cell Without Amplification

Area of Science:

• Biophysics
• Molecular Biology
• Cellular Biology

Background:

• Proteins are crucial biomolecules involved in numerous biological functions and serve as disease biomarkers.
• Quantifying proteins at the single-cell level is essential for advancing our understanding of cellular processes and disease mechanisms.

Purpose of the Study:

• To develop and apply atomic force microscopy (AFM) for the precise quantification of neurological proteins within individual cells.
• To investigate the expression levels of specifically disrupted-in-schizophrenia 1 (DISC1) protein in single cells.

Main Methods:

• Utilized atomic force microscopy (AFM) for high-resolution imaging and force mapping.
• Immobilized antibodies specific to DISC1 onto a microspot for targeted protein capture.
• Performed force mapping on single cells to visualize and quantify individual DISC1 molecules.

Main Results:

• Successfully visualized and quantified DISC1 protein at the single-cell level.
• Observed significant variation in DISC1 numbers across individual cells.
• Determined an average DISC1 count of 4.38 × 10^3 per cell, consistent with ensemble-averaged data.

Conclusions:

• The developed AFM approach enables quantitative analysis of proteins in single cells.
• This technique offers potential for in-depth studies of protein behavior and cellular responses.
• The method can advance the diagnosis of diseases and cellular abnormalities by analyzing individual cell physiology.