A developing embryo needs regular care and attention. Like trees and shrubs in an ornamental garden, our nerve cells, or neurons, were regularly pruned to shape their growth in the womb. Here we see magnified areas from the brains of two fruit flies, Drosophila, viewed under a high-powered microscope and stained purple. Their neurons (stained green) have branch-like tips called axons which were pruned back before these pictures were taken to see how they would re-grow. The neurons on the left have blossomed into a thriving network of axons, 2,000 times smaller than the average bonsai tree. The neurons on the right, which lack the guidance of a gene called unf, have failed to re-grow correctly. Human versions of such ‘nerve gardening’ genes may one day be manipulated with drugs to help damaged nerves to regenerate after brain or spinal injuries.
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.