Custom DNA: scientists flouresce DNA to visualize cell

(Photo credit: Wyss Institute) This fluorescently tagged image shows the light emitted within organelles in a human cell.

Harvard researchers at the Wyss Institute for Biologically Inspired Engineering recently created this image of a human cell enhanced by Exchange-PAINT, a method that marks certain organelles with fluorescent markers, according to the Wyss Institute's Feb. 3 press release. 

The green displays microtubules, the red the Golgi Apparatus, the yellow the peroxisomes, and the purple, the mitochondria.

One of the team leaders, Peng Yin, Ph.D, published his dissertation (will prompt to open a document) in 2012 on watching metabolic reactions take place through fluorescent tagging. At the time, however, the samples were still dead, and he was merely comparing relative levels over time.
  
This new method allows scientists not only to see objects that are extremely close together in higher resolution than ever, but also specimens that are still living. 

The goal of such imaging is to analyze processes as they occur in real time, watching each of the components interact.These images display many of those components, organelles, simultaneously, and suggest that the right combinations of markers could allow scientists to observe processes in the organelles, upholding or rejecting earlier hypotheses.