It’s difficult to imagine a factory that makes factories. Conveyor belts full of new conveyor belts; machines building machines; each pieced together with a precise blueprint and then exported for use elsewhere. In the cell nucleus, protein factories called ribosomes are assembled in a ‘factory of factories’ called the nucleolus (shown here stained in blue) and then exported to the cytoplasm to begin work. Manufacturing the cell’s estimated 15000 Ribosomes requires a special combination of tools that exist together in nucleoli. Enzymes called fibrillarin (stained here in red) and HP1β (shown here attached to a green fluorescent protein) help to build ribosomes by regulating how quickly their DNA blueprint can be read, an example of epigenetics.
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.
BPoD is also available in Catalan at www.bpod.cat with translations by the University of Valencia.