Two articles in this week's issue of Science provide insight into the function of the ribosome in bacterial protein synthesis, specifically how its structure affects decoding and translocation in Thermus thermophilus. Work led by first authors T. Martin Schmeing and Rebecca Voorhees of the MRC Laboratory of Molecular Biology, Cambridge, resolved the crystal structure of the ribosome bound to elongation factor-Tu and amino-acyl tRNA, lending insight into how EF-Tu aids decoding. A complementary paper describes the crystal structure of the ribosome bound to elongation factor-G trapped in post-translocation, which lends insight into how EF-G functions in translocation. A perspective adds more.
Two more papers have identified the F-box protein FBXL5 as a human iron sensor, which contributes to the regulation of genes related to cellular iron levels. In work led by scientists at UCLA and the University of Texas Southwestern Medical Center in Dallas, they found that cells regulate the activity of iron regulatory proteins IRP1 and IRP2 via the protein FBXL5. "FBXL5 senses iron through an evolutionarily conserved hemerythrin domain that is related to a family of iron- and oxygen-binding proteins in bacteria and invertebrates," says a related perspective article.
In news, a study from Rutgers University analyzing education and employment trends between 1972 and 2005 found that while the US continues to produce just as many scientists, the number of the highest performing of those students taking science and engineering jobs has seen a "steep drop," says the story. "The findings suggest that the United States risks losing its economic competitiveness not because of a work force inadequately trained in science, as conventional wisdom holds, but because of a lack of social and economic incentives to pursue careers in science and technology."
Finally, another news item focuses on the unusually high number of women who won Nobel Prizes this year. With four women claiming the prize, it's the first time that more than one woman has been selected in any given year. Still, only 17 female scientists have won, making up only 2.8 percent of the total number. This year's laureates, Elizabeth Blackburn and Carol Greider in physiology or medicine, Ada Yonath in chemistry, and Elinor Ostrom in economics, talk about what it will take to raise the number in a Q&A roundtable. They address issues of assuming leadership roles, finding mentorship, and cultivating a sense of scientific curiosity at an early age.