A Guide to Choosing Fluorescent Proteins

The recent explosion in the diversity of available fluorescent proteins (FPs)1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16 promises a wide variety of new tools for biological imaging. With no unified standard for assessing these tools, however, a researcher is faced with difficult questions. Which FPs are best for general use? Which are the brightest? What additional factors determine which are best for a given experiment? Although in many cases, a trial-and-error approach may still be necessary in determining the answers to these questions, a unified characterization of the best available FPs provides a useful guide in narrowing down the options.