Protein complex (yellow), DNA (red and blue)and activating protein (green)

Before any cell can divide, it must copy its DNA so there will be a complete set of genes to pass on to the new cells. The process starts at defined DNA sites called origins of replication. To find these sites, cells use a protein machine called the "origin recognition complex," or ORC. In its simplest form, the ORC starts as crescent-shaped protein complex (yellow). It wraps around and bends the DNA (red and blue). When an activating protein (green) joins the ORC, the ORC is ready to load the protein that will unwind the double-stranded DNA and further enable replication. These details may answer fundamental questions about the replication process and how errors can lead to disease. Read more... Link to external Web site

Featured in the April 19, 2012, issue of Biomedical Beat.

Learn more in the extended caption published on LiveScience Link to external Web site.