Scientists in Dundee have become among the first in the world to observe the effect of forces on DNA molecules as human cells divide.
Scientists applied barely detectable forces to the molecules
Researchers used lasers to examine the miniscule shape changes caused by tugging on the fragments.
They wanted to find out how DNA in chromosomes is held together when cells split apart.
The study was aimed at better understanding cell division, which can be used in the fight against cancer.
The research team used laser light beams to apply barely detectable mechanical forces to the molecules, which are about a millionth of a millimetre in size.
The nature of the resulting fluorescent glow enable the scientists to determine the effect.
Physicists only recently developed ways of measuring such tiny forces.
Professor David Lilley from the University of Dundee said: "These weak forces are actually more relevant to biology than larger ones, so the new approach is telling scientists a lot about how DNA molecules react to mechanical force.
"This is providing a greater understanding of very basic processes involved during cell division."
This work is the result of five years of collaboration between Professor Lilley and Professor Taekjip Ha at the University of Illinois at Urbana-Champaign.