Our bones are a mix of minerals, protein and cells. As you sit reading this, your bone matrix is being gobbled up and reshaped continuously. Bone-gobbling cells, or osteoclasts, are formed by the fusion of smaller cells called monocytes. Normally about ten or so merge into one, but in some bone diseases the process goes into overdrive creating gigantic bone-guzzling monster cells. Scientists have found that where the cell membranes (here fluorescing green) of neighbouring monocytes join, structural proteins (dyed red) in each cell come together to form a ‘zipper’. Understanding what regulates these zips will help researchers figure out why too many cells sometimes fuse and perhaps even how to unzip them.
Written by Ruth Williams
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.