The Actin Superhighway
Posted on by Dr. Francis Collins
What looks like a traffic grid filled with roundabouts is nothing of the sort: It’s actually a peek inside a tiny microchamber that models a complex system operating in many of our cells. The system is a molecular transportation network made of the protein actin, and researchers have reconstructed it in the lab to study its rules of the road and, when things go wrong, how it can lead to molecular traffic accidents.
This 3D super-resolution image shows the model’s silicone beads (circles) positioned in a tiny microfluidic-chamber. Suspended from the beads are actin filaments that form some of the main cytoskeletal roadways in our cells. Interestingly, a single dye creates the photo’s beautiful colors, which arise from the different vertical dimensions of a microscopic image: 300 nanometers below the focus (red), at focus (green), and 300 nanometers above the focus (blue). When a component spans multiple dimensions—such as the spherical beads—all the colors of the rainbow are visible. The technique is called 3D stochastic optical reconstruction microscopy, or STORM .