Optical tweezers have become the method of choice in single-molecule manipulation
studies. In this Primer, we first review the physical principles of optical tweezers and the …

The twin-supercoiled-domain model describes how transcription can drive DNA
supercoiling, and how DNA supercoiling, in turn, plays an important role in regulating gene …

We introduce magnetic torque tweezers, which enable direct single-molecule
measurements of torque. Our measurements of the effective torsional stiffness C of dsDNA …

In cells, DNA is constantly twisted, bent and stretched by numerous proteins mediating
genome transactions. Understanding these essential biological processes requires in-depth …

RNA plays myriad roles in the transmission and regulation of genetic information that are
fundamentally constrained by its mechanical properties, including the elasticity and …

Type IIA topoisomerases are essential DNA processing enzymes that must robustly and
reliably relax DNA torsional stress. While cellular processes constantly create varying …

DNA torsional elastic properties play a crucial role in DNA structure, topology, and the
regulation of motor protein progression. However, direct measurements of these parameters …

Nucleic acids are central to the storage and transmission of genetic information. Mechanical
properties, along with their sequence, both enable and fundamentally constrain the …

Multiple biological processes involve the stretching of nucleic acids (NAs). Stretching forces
induce local changes in the molecule structure, inhibiting or promoting the binding of …

DNA melting under torsion plays an important role in a wide variety of cellular processes. In
the present Letter, we have investigated DNA melting at the single-molecule level using an …