Scientific discoveries sometimes emerge from the most unexpected places. HHMI Professor Graham C. Walker, for instance, never predicted that a classroom experiment with soil bacteria would uncover a missing link in the biochemical pathway for manufacturing vitamin B12.
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As you turn the pages of this Bulletin, motor neurons that project from your spinal cord are coordinating the precise actions of more than 50 muscles in each of your arms. Each muscle is individually controlled by its own motor neuron cluster, which has a distinct identity and pattern of connectivity. read in full issue (pdf)
Using robots and other high-throughput technologies, the researchers screened more than 32,000 protein combinations, identifying 2,846 unique pairwise interactions in their study. Even so, says Fields, “We’ve only scratched the surface of what’s out there.” read in full issue (pdf)
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 Those transposons are no longer active, however, but are the molecular relics of an era when transposons ran rampant through mammalian genomes.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)
Colorectal tumors take the lives of more adult Americans than any other cancer except lung cancer, even though colon cancer is almost always curable by surgery if detected early enough. 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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HHMI investigator Richard Flavell and his team observed the first instance of genes from separate chromosomes coordinating their activities by touching each other.
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Combining high-resolution serial electron microscopic tomography, neuroelectrophysiological measurements, mathematical modeling, and computer graphics, a multi-institution team led by HHMI investigator Terrence J. Sejnowski at the Salk Institute for Biological Studies has overturned a half-century’s dogma in neurobiology.
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“It’s a way to get at virtually all of the muscles in the body, not just the major ones that we can see. Every muscle fiber is fed by the bloodstream in one way or another, so if you can really get something delivered through the bloodstream rather than in some localized way, it’s potentially a very powerful therapy.” read story