New Research Tech Makes Individual Cells Glow
A new, glowing, colorful, microscopic barcode could help biologists stick ID tags onto individual cells in cancer, HIV and other research. The tags would help researchers track more cells than ever during studies, using an adaptation of a technique already well known among biologists.
The barcodes consist of a series of colored dots that glow under ultraviolet light. The dots are fluorescent proteins, molecules originally discovered in a glowing jellyfish called the crystal jelly, but that biologists now use in experiments when they want to watch exactly what certain cells do over time. Without the fluorescent proteins, it's often difficult to distinguish individual cells seen in a mass under a microscope.
Usually, however, biologists are able to stick only one color onto a single cell. The new barcode, created by biologists at Harvard University's Wyss Institute for Biologically Inspired Engineering, lets scientists create an enormous number of possible tags with various color combinations: blue-green-red versus green-green-green-green versus red-yellow-green-blue-red, and so on. The colored dots don't necessarily need to sit in a straight line, either; they may be arranged above or below one another.
A foundation constructed from pieces of DNA holds the fluorescent proteins in place. The Wyss researchers used a technique called "DNA origami" to manipulate pieces of DNA to fold into various, nano-sized shapes. The folds were held in place with smaller pieces of DNA, each of which acts like a staple holding two parts of the DNA strand together. The shapes are stiff and sturdy, according to the barcode's creators.
"The intrinsic rigidity of the engineered DNA nanostructures is this method's greatest advantage," Peng Yin, a Wyss biologist and computer scientist who led the research, said in a statement. "It holds the fluorescent pattern in place without the use of external forces."
Yin and his colleagues attached one of their glowing barcodes onto a yeast cell in order to show the barcode is a useable tag. They now need to test what happens if they mix several different barcodes in a Petri dish full of cells.
The researchers are publishing their work today (Sept. 24) in the journal Nature Chemistry.