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Nobel Laureate Roger Tsien dies at 64 Biochemist advanced the use of green fluorescent protein as a ubiquitous biological marker Roger Y. Tsien, the Nobel Prize-winning biochemist who helped make green fluorescent protein (GFP), one of the most valuable tools for examining biological systems, has died. He was 64. Tsien, who was a professor of pharmacology, chemistry, and biochemistry at the University of California, San Diego, died on Aug. 24 while bicycling on a trail in Eugene, Ore. Tsien’s family has declined to disclose the cause of death, according to a UCSD spokesman. Tsien The news has shocked and saddened not only colleagues and friends, but the science community at large. Amy Palmer, a chemistry and biochemistry professor at the University of Colorado, Boulder, was a postdoctoral researcher in Tsien’s lab during the early 2000s. “For me, he was an inspiration for how to do science: to be constantly curious, to never stop exploring, and most important, to appreciate the beauty of science and have fun,” she says. Tsien is most well-known for his work on GFP, which scientists now routinely use to tag and observe proteins in cells. He shared the 2008 Nobel Prize in Chemistry with Osamu Shimomura, emeritus professor at the Marine Biological Laboratory, in Woods Hole, Mass., and Martin Chalfie, professor of biological sciences at Columbia University.
Shimomura identified GFP, which glows green under blue to ultraviolet light, in jellyfish; Chalfie devised methods to link GFP to other proteins, making it a biological marker; and Tsien synthesized a whole class of related proteins that fluoresced even more brightly—and in an array of different colors. Tsien “was a remarkable and spectacularly innovative scientist who was always seeing the next wonderful goal,” Chalfie says. “Then he would do something amazing and different to accomplish that goal.” Tsien was born in 1952 in New York City. He excelled at science from an early age, winning first prize in the prestigious Westinghouse Science Talent Search for high school seniors in 1968. He graduated summa cum laude in chemistry and physics from Harvard University in 1972, then earned his Ph.D. at the University of Cambridge in 1977. After several years at UC Berkeley, he moved to UCSD in 1989. “Roger was a brilliant and creative scientist,” says MIT chemistry professor Stephen J. Lippard, who once worked with Tsien. “His insights inspired many to pursue the chemistry of biological processes. Importantly, he provided the tools to allow them to do so. He will be sorely missed.”—ELIZABETH WILSON
OVERHEARD
“This is the best news that we’ve had in my 25 years doing Alzheimer’s clinical research. It brings new hope for patients and families most affected by the disease. Obviously these results need to be confirmed in Phase III.” —Stephen Salloway, director of the memory and aging program at Butler Hospital, in Providence, speaking at a press conference about Phase Ib clinical trial data showing that Biogen’s aducanumab antibody reduces amyloid-β plaques in the brains of Alzheimer’s disease patients. A team he worked with published the data last week in Nature (DOI: 10.1038/nature19323).
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C&EN | CEN.ACS.ORG | SEPTEMBER 5, 2016
Resizing the chemical elements Ever stop to contemplate the size of an atom or ion? Martin Rahm, Roald Hoffmann, and Neil W. Ashcroft have. For consistency’s sake, these Cornell University scientists have just completed a systematic theoretical estimate of the atomic and ionic radii of the first 96 elements of the periodic table (Chem. Eur. J. 2016, DOI: 10.1002/ chem.201602949). They say the size question has been a natural one to ask over the past century, given that we have been collecting good experimental data on atoms in every form of matter and have increasingly reliable theories about the nature of atoms. Still, the Cornell group posits, there’s no unique answer to the query: “What is the size of an atom or an ion?” One can just come up with carefully defined—but, in the end, arbitrary—criteria, Hoffmann says. And many researchers have. Ultimately, the validity of one or another definition is measured by how well it aligns with experimental data, in particular with crystal structures. The importance of having standardized estimates such as the Cornell team’s is to help understand ambiguities when rationalizing material properties, such as crystal packing and molecular structures. Rahm, Hoffmann, and Ashcroft began by setting up a size limit. Building on prior estimates, they settled on a cutoff being the average distance from the nucleus where the electron density falls to 0.001 electrons per bohr3, where bohr is the Bohr radius, which is 0.53 Å. The radii were then derived using relativistic all-electron density functional theory calculations. This approach provides radii that “agree remarkably well” with experimental estimates of radii derived from crystal structures, the researchers note.—STEVE RITTER
CREDIT: UC SAN DIEGO HEALTH
OBITUARY
