A mesh of stringy tubes stretches out inside us – inside every single cell in fact. Among its many vital jobs, the endoplasmic reticulum (ER) helps to form the proteins that our cells need to move, grow and repair. A faulty ER can cause fatal diseases. Until now, though, large areas of the ER were thought to be fairly uninteresting flat sheets. It took a new technique called structured illumination microscopy to examine their structure in finer detail than before, leading to a discovery that rewrites all the biology textbooks. The flat sheets are in fact webs of tiny tubes that bend, adapt and remodel over time – perhaps preparing different areas of the ER for specific tasks. The newly-revealed structure (its 3D shape highlighted here with different colours) presents an exciting new set of mechanical parts for researchers to investigate, in healthy cells and diseased ones, too.
Written by John Ankers
BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.