It’s been estimated that humans have between 20,000 and 25,000 genes. In order to understand our vastly comprehensive genetic makeup, we need to be able to capture clear images. Fortunately, researchers at the California Institute of Technology have recently discovered a way to visualize gene expression through magnetic resonance imaging (MRI).
A team of scientists led by assistant professor chemical engineering Mikhail Shapiro found that by increasing the quantity of aquaporins, a natural protein that barricades water molecules, analysts could produce clearer cell visualizations. Eventually, this new technique would allow physicians to conduct non-invasive gene expression observations without surgical procedures like biopsies. The team published their discovery in Nature Communications journal this past December.
MRI only allows us to see physiological functions like blood flow. Before CalTech’s discovery, the imaging wasn’t detailed enough to let us examine the activity of certain cells. By linking aquaporin to specific genes (also known as reporter genes) analysts can see when those genes are turned on as they will overexpress aquaporin, making it look darker under diffusion-weighted MRI.
Shapiro’s team tested the technique by implanting brain tumors in mice. The mice ingested a drug to trigger the tumor cells to express the aquaporin reporter genes, giving the tumor a dark shade in MRI images.
"Overexpression of aquaporin has no negative impact on cells because it is exclusive to water and simply allows the molecules to go back and forth across the cell membrane," Shapiro said in a CalTech press release. Aquaporin is a very convenient way to genetically change the way that cells look under MRI."