Peptide nucleic acid based tension sensor for cellular force imaging with strong DNase resistance

Area of Science:

• Biomaterials Science
• Cell Biology
• Molecular Biology

Background:

• Deoxyribonucleic acid (DNA) is widely used for tension sensors to measure cellular forces.
• Existing DNA tension sensors are susceptible to degradation by deoxyribonucleases (DNases).
• DNase activity can compromise sensor function, leading to inaccurate cellular force imaging.

Purpose of the Study:

• To develop DNase-resistant tension sensors for cellular force imaging.
• To evaluate alternative biomaterials like peptide nucleic acid (PNA) and modified RNA for tension sensor construction.
• To compare the performance of DNA, PNA/DNA, dsRNA, and PNA/RNA tension sensors.

Main Methods:

• Synthesized four types of duplexes: dsDNA, PNA/DNA, dsRNA, and PNA/RNA.
• Assessed DNase resistance against soluble DNase I and membrane-bound DNases.
• Evaluated cellular force imaging capability, signal-to-noise ratio, and specificity.
• Tested material robustness and stability in DNase-expressing cellular environments.

Main Results:

• PNA/DNA, dsRNA, and PNA/RNA duplexes demonstrated significant DNase resistance.
• PNA/RNA sensors exhibited low signal-to-noise ratios, while dsRNA sensors showed high non-specific signals.
• PNA/DNA tension sensors provided the highest signal-to-noise ratio and specificity in reporting cellular forces.
• PNA/DNA sensors remained stable and functional in the presence of DNase-expressing cells.

Conclusions:

• Peptide nucleic acid/DNA (PNA/DNA) hybrids are effective DNase-resistant materials for tension sensors.
• PNA/DNA sensors maintain force-reporting capabilities and stability in challenging cellular conditions.
• This advancement expands the utility of tension sensors in cell mechanobiology research, particularly in environments with DNase activity.