doi:10.1038/nindia.2013.69 Published online 28 May 2013
Researchers have devised a new cell biology technology that can simultaneously measure the pH in two different places inside one cell1. The technology using two DNA nanomachines is promising as a powerful tool to study problems in intracellular traffic and to customize therapies for infectious and autoimmune diseases.
The simultaneous pH sensing technology called 'SimpHony' uses two different kinds of DNA nanomachines, each carrying a distinct pH sensing module, latching onto two different proteins inside a cell and reporting the pH around them. It is thus possible to find out the abnormal acidity of the contents of cellular organelles with altered morphology.
The researchers targeted DNA nanomachines in different cellular destinations either by tagging them to different proteins or by interfacing with a protein recognition motif. This targeting was later utilized to label different organelles with two different DNA nanomachine in a same cell and report high resolution pH dynamics of individual organelle simultaneously. By combining these two, SimpHony revealed that perturbation of organelle morphology leads to defective acidification which may explain altered protein trafficking in these compartments.
So far, only a single type of DNA nanodevice had been shown to be functional at a time, inside living systems. This is the first report of multiplexing DNA devices inside the same living cell opening up avenues for multipronged approaches in sensing and therapy in living systems.
The team has outlined a strategy to position multiple DNA nanodevices at will in multiple, distinct, sub-cellular locations within the same cell. "This strategy is highly general in that it is in a 'plug and play' format immediately implementable by researchers," one of the researchers Yamuna Krishnan told Nature India.
The authors of this work are from: National Centre for Biological Sciences, Bangalore, India and Laboratoire Interdisciplinaire de Physique, CNRS-Université Grenoble I, Grenoble, France.