Scientists have found that the movement of a protein, which exists within the bundles of hair-like protrusions atop hair cells, exhibits the hallmarks of a repair and renewal process.

Reported in the Cell Reports journal, the researchers, working at Case Western Reserve University School of Medicine, genetically modified zebrafish so that a certain protein present in the bundles, fascin 2b, was fused with a fluorescent green protein, allowing them to be studied in greater detail than usual.

The scientists were surprised to find that the proteins constantly circulated around the bundles - also known as sterocilia - seemingly moving to repair breaks in the structures that occurred when the zebrafish were exposed to loud noise.

Conventional understanding theorised that hair cells were crafted out of cellular scaffolding proteins that experienced no change or interior circulation, but the discovery completely questions this understanding.

Senior author Brian McDermott was quoted saying: "We found that the constant, dynamic movement likely contributes to the permanency of the hair bundle structure to last a lifetime, or 70 to 90 years in human terms."