Protocol to analyze chromatin-bound proteins through the cell cycle using Chromoflow flow cytometry

Area of Science:

• Molecular Biology
• Cell Biology
• Biochemistry

Background:

• Conventional methods for measuring chromatin-bound proteins, such as subcellular fractionation and immunofluorescence microscopy, can be labor-intensive and may not provide quantitative single-cell resolution.
• Existing techniques often require normalization steps to account for technical variability, adding complexity to the analysis.

Purpose of the Study:

• To introduce Chromoflow, a novel protocol for the quantitative analysis of protein levels on chromatin in single cells.
• To enable the assessment of chromatin-bound protein levels throughout the cell cycle.
• To provide a streamlined and robust method that minimizes experimental variability.

Main Methods:

• Chromoflow utilizes flow cytometry for high-throughput quantitative analysis of nuclear proteins.
• The protocol includes detailed steps for cell harvesting and nuclear extraction.
• A sample barcoding strategy is employed to multiplex samples, reducing antibody staining variability and eliminating the need for normalization.

Main Results:

• Chromoflow enables accurate and quantitative measurement of chromatin-bound protein levels at a single-cell resolution.
• The protocol allows for the analysis of protein dynamics throughout the cell cycle.
• Multiplexing via barcoding enhances throughput and reduces experimental variability.

Conclusions:

• Chromoflow offers a powerful and efficient method for studying chromatin-bound proteins.
• This protocol facilitates quantitative analyses of protein levels in single cells and across the cell cycle.
• Chromoflow simplifies experimental workflows and improves the reliability of protein quantification in chromatin studies.