Channel Hoppers Land Chemistry Nobel Jim Giles Two Structural Biologists Credited With

news Channel hoppers land chemistry Nobel Jim Giles Two structural biologists credited with

A. ABBOTT transforming our understanding of how cells work have been awarded the 2003 R. BOREA/AP Nobel Prize in Chemistry. Peter Agre of Johns Hopkins University in Baltimore and Roderick MacKinnon of the Rockefeller University in New York share the prize for experiments that revealed the intri- cate workings of the channels that allow ions and water to enter and leave cells. MacKinnon is perhaps the most widely tipped Nobel winner of recent years.In a land- mark 1998 paper (D. A. Doyle et al. Science 280, 69–77; 1998), he and his colleagues pro- vided the first detailed three-dimensional Roderick MacKinnon (left) and Peter Agre’s work on cell-membrane proteins has won them recognition. picture of a protein that acts as a channel to control the flow of potassium ions across cell deserved a Nobel.“His work is a tour de force,” Kuhajda and P. Agre J. Biol. Chem. 263, membranes. This channel is immensely says John Walker, a structural biologist at the 15634–15642; 1988). “No one had seen it important to neuroscientists, as the flow of University of Cambridge, UK. “The award is before,but we found that it was the fifth most potassium ions helps to generate the voltage absolutely spot on and richly deserved.” abundant protein in the cell,” says Agre. pulses that brain cells use to communicate. MacKinnon was on holiday when the “That’s like coming across a big town that’s Before MacKinnon’s paper, many biolo- prize was announced, and couldn’t be not on the map.It gets your attention.” gists had questioned whether the technique informed directly by the Nobel prize com- The protein, now known as aquaporin 1, he used — X-ray crystallography — could be mittee. “My assistant called to tell me but I is a cell-membrane channel that lets water used to image membrane proteins. The didn’t believe him,”says MacKinnon. “I had pass through, but not other substances.“We method involves forming crystals of the pro- to do a Google search on ‘Nobel prize’.” weren’t looking for the water channel,” says tein to be studied, but researchers had previ- When asked what he would do with the prize Agre.“We were very lucky.” ously failed to get large enough quantities of money, MacKinnon suggested that buying a “Agre’s work changed the way we think channel proteins for effective crystallization. mobile phone might be a good idea. about membranes,” says Stefan Hohmann, a MacKinnon experimented with potassium- Agre’s breakthrough came in 1988, when cell biologist at Gothenburg University in channel proteins from many different he cracked a problem that had survived more Sweden.The studies could have many medical organisms, eventually extracting enough than a century of study — the way in which spin-offs,he adds.Aquaporins play an impor- from the bacterium Streptomyces lividans. cells absorb and flush out water.Agre and his tant role in the brain swelling that can occur When he went on to describe how such colleagues, while studying cell membranes, after stroke, for example, and blocking their channels open, close and prevent other ions identified a previously unknown protein in function could help to reduce this effect. I from entering, many colleagues felt that he red blood cells (B.M.Denker,B.L.Smith,F.P. ± www.nobel.se

Economics prize for duo who resolved random results

Philip Ball such indices over analysis, and helps The Nobel prize for economics has been time — known as to identify causal awarded to researchers whose mastery of time series — using connections P. GARDIN/AP mathematical methods could have a concept that he between data sets. J. MCCOMBE/AP consequences way beyond the ‘dismal science’. called autoregressive “If you are going The prize was awarded to Robert Engle conditional to give a prize for of New York University and Clive Granger of heteroskedasticity economic time- the University of California, San Diego, for (ARCH). Models of series analysis, these their development of methods to analyse market volatility are the two to give it apparently random fluctuations in Risk assessor: based on the idea Clive Granger: on top to,”says economist economic data. Robert Engle. are now widely used of time series. Paul Ormerod of The dynamics of economic statistics — by market analysts London-based including indices of national output, stock and bankers to evaluate risk. company Volterra Consulting. prices and exchange rates — pose a Welsh-born Granger, meanwhile, Besides economics, the winners’ methods daunting challenge to scientific study. These developed statistical methods that help have found widespread application in the indices tend to vary unpredictably over analysts to deal with time series that analysis of nonlinear systems in such diverse time, with periods of high volatility fluctuate around a moving baseline, by areas as climatology, physiology and interspersed with calmer spells. combining them in a way that removes their physics. Granger’s techniques have proved to Engle, an American who trained as a long-term drift, through a phenomenon that be particularly versatile and have been used, physicist at Cornell University, devised he called co-integration. This makes such for example, to assess human influences on statistical models to describe the plots of data amenable to conventional statistical climate change. I