Chromophores, a new class of reporters

ResearchBlogging.orgA new Nature letter has the potential to abnormally extend (until extinction) the whole spectrum of reporter genes. So far, "reporters" were those genes coding for an easily detectable product (i.e., those coding for fluorescent or luminescent proteins). Wei Min and other Harvard's colleagues introduced a new technique, namely stimulated emission microscopy, that seems able to turn into mini-lasers any non-fluorescent light-absorbing molecule. It means that several chromophores, such as haemoglobin and cytochromes, can now be directly detected through a new contrast mechanism for optical microscopy which is orders of magnitude more sensitive than absorption, is not subject to interference from other chromophores in the sample, and is amenable to three-dimensional sectioning. This open the race to the intelligent design of new chromo-reporters able to produce images of unlabelled, non-fluorescent molecules at sub-diffraction (nanoscale) resolution. Seeing is believing. The potential to kill the field of reporters is easily explained: who ever need a "reporter" when you can spy in a cell the whole bunch of molecular processes with resolutions at googlemeter per googlesecond?

Min, W., Lu, S., Chong, S., Roy, R., Holtom, G., & Xie, X. (2009). Imaging chromophores with undetectable fluorescence by stimulated emission microscopy Nature, 461 (7267), 1105-1109 DOI: 10.1038/nature08438