Scott Sternson has always wondered what drives behavior, especially those fundamental motivations required for survival. Hunger, for example, is so crucial that it must be evolutionarily “hard-wired” deep within the brain. After all, as Sternson observes, “if the animal doesn’t eat, it dies.” read story
“Every morning we took a short walk to the local market for groceries. One day, on the way back, there was a thunderstorm, so we took shelter in a little shed. After the rain, I said, ‘Let’s go home now.’ I looked at my grandmother’s face and it was completely without expression. ‘Home?’ she asked. ‘Where is home?'” read in full issue (pdf)
With the help of genetically engineered mice whose livers turned into glowing light bulbs, researchers at the Salk Institute for Biological Studies have illuminated the underpinnings of an insidious and growing health concern – type II diabetes. read story
Imagine your mechanic yanked the engine out of your car. You buckle up, turn the ignition, and off you drive, undoubtedly with a shattered notion of how automobiles work. That’s essentially what researchers led by HHMI investigator Pietro De Camilli experienced earlier this year when they eliminated a brain protein from mice thought to be an engine for transmitting nerve impulses. read in full issue (pdf)
Some lab mice can see the world in a whole new light, thanks to HHMI investigator Jeremy Nathans and his colleague Gerald H. Jacobs. Their findings provide insight into the remarkable plasticity of mammalian brains, and shed light on a plausible means by which humans may have acquired the ability to see many colors. read in full issue (pdf)
Elaine Fuchs used to do crossword puzzles as a diversion from her undergraduate studies. With crosswords, every solved clue creates new hints to help solve neighboring clues. Fuchs, an HHMI investigator at The Rockefeller University, has followed a similar approach throughout her professional life. By honing each experimental finding into a new set of tools, she has probed deeper into the question that first piqued her curiosity three decades ago. read in full issue (pdf)
Embryonic stem (ES) cells are plain enough to look at, forming a nondescript clump within the hollow ball of an early embryo. But that generic character is key to their magical rejuvenating potential. Unlike all other cells, which are preordained toward a specialized form and function, ES cells have a clean slate. The developing embryo can mold them into any cell type it needs.
If the thought of invasive medical procedures makes you queasy, HHMI investigator Owen N. Witte points out that “there’s a noninvasive trend in medical diagnosis—to measure things inside the body without having to stick tubes in a patient or do an operation.” Witte, a researcher at the University of California, Los Angeles, has recently furthered this trend, leading a team from three medical institutions to develop a noninvasive technique based on positron emission tomography (PET). The scientists captured three-dimensional views of one body component never before seen from the outside—the immune system.
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“About 40 percent of the sequences in our genome, and in the mouse genome, are actually transposon sequences,” Xu says. Those transposons are no longer active, however, but are the molecular relics of an era when transposons ran rampant through mammalian genomes. read in full issue (pdf)
A fountain of youth springs from within the brain of every mammal, report HHMI investigator Alexandra L. Joyner and her former postdoctoral associate Sohyun Ahn in the October 6, 2005, issue of Nature. No, the two researchers haven’t unlocked the secret to immortality. But their discovery of a method to visualize an elusive population of stem cells that has the potential to regenerate nerves and other brain cells may explain how certain regions of the brain rejuvenate themselves. Moreover, the findings may allow researchers to tap the revitalizing powers of stem cells for repairing injured and diseased brain tissue.
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