Biophysical-to-DNA Catalytic Cumulative Birecorder for Measuring Continuous Membrane Fluidity

Area of Science:

• Cell Biology
• Biophysics
• Molecular Biology

Background:

• Recording cellular biophysical processes is essential for understanding cell behavior.
• Developing methods to continuously monitor membrane fluidity has been a significant challenge.

Purpose of the Study:

• To develop a novel system for recording continuous membrane fluidity events.
• To enable in situ imaging and digital quantification of membrane dynamics.

Main Methods:

• Engineered DNAzyme probe sets were used to create a biophysical-to-DNA catalytic cumulative birecorder (BioDIMER).
• BioDIMER accumulates bimodal signals responsive to transient membrane encounters, recording events in both fluorescent signals and DNA unique molecular identifiers (UMIs).
• In situ imaging captured spatiotemporal information, while UMI sequencing provided digital quantification of membrane fluidity events.

Main Results:

• The BioDIMER system successfully recorded continuous membrane fluidity changes in various cell types and states.
• Differential membrane fluidity dynamics were observed during cell cycle phases, showing an initial decrease followed by an increase.
• Cardiac hypertrophy was associated with enhanced membrane fluidity, whereas cellular senescence led to a significant reduction.

Conclusions:

• The BioDIMER method provides a powerful tool for multidimensional interpretation of membrane fluidity timing.
• The findings highlight the highly dynamic organization of cell membrane components.
• This approach offers new insights into cell membrane responses to different physiological and pathological states.