5-Prime | Prions - The Terminators What are they? The prion protein (PrP) is a widely expressed, membrane-associated protein transcribed from the PRNP gene, which is highly conserved among mammals. PrPs exist in two forms: a common, harmless alpha-helical form, and a rare beta-sheet form that causes fatal mammalian brain diseases such as scrapie, Creutzfeld-Jacob disease, and mad cow disease. Prion diseases collectively are called spongiform encephalopathies, causing sponge-like vacuoles in

 NETWORKED: (A) Effects of the gal4D+gal perturbation are superimposed on a gene interaction network… Click for larger version (92K) Large-scale biology once conjured images of brute-force genetic screens resulting in collections of mutants. More recently, it has meant genome sequencing on unprecedented scales. But today, as this issue's Hot Papers demonstrate, the leading edge in large-scale biology is proteomics. As in the large-scale efforts of the past, researchers rely on simp

Courtesy of California Department of Health Services Faster than an injection, more reinforcing than crack cocaine: Smoking a cigarette speeds nicotine to the brain faster than any other delivery method, giving smokers precise control over their exact nicotine dose with each puff they take. It turns out that those two attributes--speed and control--greatly enhance nicotine's addictive effect on the brain. "It's not just the drug, but how you take it," says Timothy Baker, associate director, U

Quitting the habit means fighting nicotine addiction. "It's not like drinking, where you have a huge social drinking population of nonaddicted people. People who smoke regularly tend to be addicted," says Timothy Baker, associate director, University of Wisconsin Center for Tobacco Research and Intervention. With nearly half the US adult population lighting up in 2000, public-health researchers are hard-pressed to figure out what helps--and what doesn't--in the fight against nicotine addictio

Courtesy of Vector Tobacco  READY, SET, STOP: Quest's 'step down' low- and no-nicotine cigarettes. The major toxins in cigarettes, perhaps surprisingly, don't come from the chemicals that manufacturers add. "The carcinogens mostly come from the burning of tobacco," says Kenneth Warner, director, University of Michigan Tobacco Research Network. Just burning tobacco also produces carbon monoxide, a big contributor to heart disease. So, tobacco companies are turning to science to make ciga

Front Page | New Lead for Sporadic CJD Cause; Enlisting Evolutionary Help; Science Seen Courtesy of Astrid & Hanns-Frieder Michler/Science, Photo Library  SCIENCE SEENA cross section of a madonna lily anther shows four pollen sacs filled with pollen grains (blue dots with red nuclei). Some of the pollen grains of this Lilium candidum are undergoing meiosis, the process whereby a normal diploid cell divides to form four haploid cells, called gametes.   Courtesy of Keith Welle

Front Page | New Pill Box Possibilities; Super Monkey Moms; Science Seen PhotoDisc GENE THERAPY | New Pill Box Possibilities "Take two genes and call me in the morning"--not exactly what one would expect a family doctor to say, but it could become a common prescription if a new "gene pill" pans out. James Hagstrom, vice president of Mirus, Madison, Wis., says "This technology would be extremely useful for wide ranging therapeutic applications." Hagstrom moderated a talk at the recent Kno

Gin Lane, William Hogarth (1697-1764); Courtesy: McCormick Library of Special Collections, Northwestern University Library For a teenager, sneaking a beer is one thing; shooting up heroin is quite another. Missing a parentally imposed curfew is almost expected; disappearing for days is heart-wrenching. There is risk, and then there is risk. Figuring out what differentiates experimenting teenagers from delinquents and lifelong reckless hearts is not easy; behaviors typically stem from complex

Image: Courtesy of Mignon Fogarty  LEARNING ABOUT RESISTANCE: Most cancers engage multiple growth factor, angiogenic, cell cycle, and apoptosis pathways. Frequently, redundant pathways exist, so that as drugs shut one pathway down another pathway takes over. This is one way that cancers become resistant to targeted agents. Early stage tumors tend to secrete a small number of pro-angiogenic factors, whereas late stage tumors secrete a larger number of pro-angiogenic factors. Targeted anti

The Faculty of 1000 is aWeb-based literature awareness tool published by BioMed Central. For more information visit www.facultyof1000.com. Although controversial fetal stem cells hog the limelight, hematopoietic stem cells (HSCs), which give rise to the entire adult blood system, quietly facilitate high-dose chemotherapy on a regular basis in hospitals worldwide. But HSCs have not been without intrigue--whence they come and how they arise in early development remains mysterious. Now, two colla

Image: Erica Johnson A healthy volunteer died in a Johns Hopkins asthma study because the researcher missed information about an inhalant's potential dangers. A vendor to a large pharmaceutical company says that the firm wasted almost two years trying to isolate a compound, not realizing that fellow colleagues had already obtained a patent for it. University of Minnesota researchers, as many others do, discovered after three years of research that results they were writing up had already been

Oncologists often describe cancer as a seed that grows in the body's soil. For these seeds to become tumors, the "soil" must be stocked with nutrients such as growth factors to help them proliferate. "Cancer is not a single-cell disease but involves cancer cells and how they collaborate or cooperate with surrounding cells," says Leland Chung, director of molecular urology and therapeutics at Winship Cancer Institute, Emory University School of Medicine. New approaches to starving cancer cells fi