December 23, 2013
3D Force Microscopes
Like most students I know, it took a basic biology class in my early years of college. I never really had a head for the subject, which turned out to be a pretty profound realization since at the time my major was environmental sciences/wildlife conservation. Even so, as I do with many subjects, I found it fascinating. I may not get it, but it is still an interesting field of study. I especially loved those days in lab when we brought out those really cool microscopes and got a much closer look at what makes up our world. I remember taking a sample of my own skin and looking at it under the lens, which in turn made me disgusted with my own flesh for many days following. Little did I know that these impressive pieces of technology were so limited in what they could show us. Sure, I knew that much more powerful microscopes existed, but even those have been somewhat limited by their ability to study membrane proteins in that they were only able to explore a single dimension. Now, technology has finally allowed for this dimensional barrier to be broken, giving researchers the ability to view these cellular gatekeepers in 3D.
As mentioned above, membrane proteins are often referred to as the gatekeepers of a cell, allowing molecules to pass in and out. Until now, force microscopes, which were used to study them, could only view them in a single dimension because of their design. They work by using a tiny needle to slide across the surface of the specimen being studied. Normally, they measure the force the needle is exerting on the specimen (thus the name) by bouncing a single laser off of the arm that holds the needle in place. As it moves it deflects light that is interpreted by computers to give the viewer an impression of the membrane. Think of it like how a needle of an old record player slid across the surface of the record to read them. In addition, because of this limitation, the specimen needed to first be crystallized, which means it was frozen. This made it impossible to study the membrane proteins during their natural interactions with neighboring cells. Recently, researchers from the University of Missouri have developed a three-dimensional force microscope that is not so limited. Gavin King, assistant professor of physics and astronomy, and Krishna Sigdel, postdoctoral in the Department of Physics at the College of Arts & Science at MU, accomplished this by using a traditional one-dimensional force microscope as a guide while adding an additional laser that could measure the second and third dimensions of the needle’s movement, which in turn gives researchers a more dynamic view of the membrane and the changes that it undergoes in a more natural environment.
So, you might be asking yourself “what’s the big deal?” Why should we care about a breakthrough in how scientists are able to study the membrane proteins? Because this new innovation could allow for a better understanding of how a protein’s shape dictates its function, which could not be done with frozen specimens. In studying this, researchers can better learn how drugs will bind together and interact with the cells of the body. Using this new information, pharmaceutical companies could determine which molecules to pursue when developing new treatments, which could also lead to bring new drugs to the market much faster than previously possible. Proof that even seemingly small innovations in science and technology can have potentially incredible results.
Image Credit: Asylum Research