Clear as Day

The more light your eyes can take in, the better the picture you see, and the lens at the front of your eye is transparent to help this. Most body cells contain lots of membranes – they have important roles like manufacturing cellular components, but they scatter light and aren’t transparent. Cells in the lens become transparent by losing all but their most vital internal membranes as they develop and move towards the middle of the lens: the central cells (shown here in a chick’s eye) are flatter, with rounder nuclei (blue). It wasn’t known how the membranes were lost until recently, when scientists discovered a structure called the excisosome. This forms inside cells and breaks down the membranes, possibly by stripping them apart into the proteins and lipids they’re made of. Current research implies that excisosomes form in the lenses of all animals, helping us understand how our eyes develop.

Written by Esther Redhouse White

Esther Redhouse White

Writer

A recent Biochemistry graduate from York, Esther has worked on bacterial killing proteins and genetic switches in worms. In her spare time she likes visiting museums full of skeletons.

• Image from work by M.Joseph Costello and colleagues
• Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill, NC, USA
• Image originally published under a Creative Commons Licence (BY 4.0)
• Published in PLOS One, August 2016