Organic Chemistry Seminar
Positions: Current: Professor of Chemistry at University of Chicago 1994: B. Sc in Chemistry at the Women’s Christian College – a small liberal arts college at the University of Madras 2002: PhD in organic Chemistry at the Indian Institute of Science, Bangalore, India 2001-05: “1851 Research Fellow”, University of Cambridge, UK. This is an independent fellowship awarded by the Royal Commission for the Exhibition of 1851 that has supported outstanding scholars for over ~100 years including Rutherford, Dirac, James Chadwick, Cockroft, Aaron Klug, Homi Bhabha, Sydney Brenner and Alex Todd among others. 2005-2013: Yamuna returned to India, set up her independent lab at the National Center for Biological Sciences in Bangalore in 2005 and 8 years later (2014) found herself at the Department of Chemistry at the University of Chicago where she has been ever since. Research: Her lab has pioneered the application of DNA nanotechnology in living systems. She developed DNA-based nanodevices to sense and image the chemical contents of sub-cellular organelles in live cells and animals. In doing so, she developed DNA nanodevices into a next-generation targeting platform, where the accuracy reaches sub-cellular precision. Krishnan’s DNA-nanodevices have unblocked decades-old bottlenecks that have hindered the analysis of ions in organelles and enabled the discovery of new organellar ion channels and transporters.
I have been interested in exploring how the ionic milieu within an organelle facilitates its lumenal biochemistry and thereby, organelle function. To map these lumenal chemistries, my lab developed a DNA-based, fluorescent reporter technology to quantitatively map ions such as H+, Cl- and Ca2+ within organelles (1). We can now interrogate organelles of cells in culture, in live organisms (2) and in human patient cells (3,4). Our most recent reporter for absolute membrane potential ended a previous misconception by showing that many organelles do in fact, have membrane potential (4). Today I will discuss two new reporters for organellar Na+ and K+ : the final pieces needed to build an electrochemical model for organelle membranes (5,6). The only existing electrochemical model of a biological membrane is that of the neuronal cell membrane, first developed by Hodgkin and Huxley in 1952 (7). To accomplish this for organelles we will need input from physicists, cell biologists and electrophysiologists.