Why are our tissues elastic?

Think about how much you move – from walking, reaching and turning to the less obvious but vital tasks such as breathing and pumping blood around the body.

One of the components in tissues such as skin, lungs and blood vessels that allow them to survive the ride is elastin, which forms elastic fibres.

And a new study has identified a structure within the molecule that seems to act like a shock absorber.

The discovery “answers the mystery of how our bodies accommodate our living tissue without it being torn to shreds by its interaction with so many moving parts”, says researcher Prof Tony Weiss, from the University of Sydney.

The study, published online this month in the Proceedings of the National Academy of Sciences, looked at the structure of tropoelastin, a building block of elastin protein fibres.

The molecule has a coil-shaped component at one end, which provides elasticity, and a foot-shaped part at the other, and they are connected by a bridge, which appears to act like a shock absorber, according to the release.

“This tiny shock absorber neatly connects specialised molecular parts: one part is dedicated to elasticity and another part dedicated to binding living tissue.

“It performs the same function for humans at a molecular level as shock absorbers do in a car; we can enjoy a smooth ride because they keepthe body of the car from being violently rattled by the movement of the wheels.”