Biomedical Beat - A monthly digest of research news from NIGMS

December 19, 2006

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The National Institute of General Medical Sciences (NIGMS), one of the National Institutes of Health, supports all research featured in this digest. Although only the lead scientists are named, coworkers and other collaborators also contributed to the findings. To read additional news items, visit NIGMS News. To check out other free NIGMS publications, go to the order form.

Cool Image: Cholesterol and Huntington's Disease

Cholesterol and Huntington's Disease. Courtesy of Cynthia McMurray.
High res. image (32 KB JPEG)

This web-like structure shows the abnormal accumulation of cholesterol in a mouse brain cell that contains an aberrant protein linked to Huntington's disease, a fatal condition marked by a progressive degeneration of brain nerve cells. While the gene underlying the disease has been identified, little is known about how it leads to such neuronal damage. But the discovery that cholesterol builds up in mouse brain cells expressing the Huntington's protein could offer new clues for understanding the mechanism of the disease in humans. Courtesy of Cynthia McMurray, a molecular biologist at the Mayo Clinic.

This work was also supported by the National Institute of Neurological Disorder and Stroke at NIH.

Full story (Link no longer available)
McMurray home page
Article abstract (from the December 15, 2006, issue of Human Molecular Genetics)

Worm Research May Help Clear the Air

Results of a recent study show that microscopic worms can get hooked on nicotine. Geneticist X.Z. Shawn Xu of the University of Michigan Medical School discovered that genes involved in how cells react to external stimuli play a role in nicotine-dependent behavior. The research could open the door to identifying risk factors and new treatments for tobacco addiction. Xu and his team also found that worms display behavioral responses to nicotine exposure similar to those observed in mammals, making the worms a useful model for substance abuse studies.

This work was co-funded by the National Institute on Drug Abuse and the National Eye Institute at NIH.

Full story
Xu lab home page
Article abstract (from the November 3, 2006, issue of Cell)

Moving Toward Molecular Machines

A new device made entirely of DNA and measuring just millionths of an inch in each dimension marks a huge step toward creating molecular machines. The device, developed by New York University chemist Nadrian C. Seeman and his graduate student Baoquan Ding, mimics the action of a construction crane with a fixed base and a rotating arm. By altering the sequence of the DNA components, the scientists can program the arm's position. Scientists predict that controllable, DNA-based devices like this will pave the way for sophisticated nanotechnology tools capable of assembling nanoelectronics, encrypting information, and constructing made-to-order pharmaceuticals and research tools.

Full story
Seeman lab home page
Article abstract (from the December 8, 2006, issue of Science)

Gender-Bending Flies Shed Light on Aggression

Fighting male fruit flies. Courtesy of the Kravitz Lab.
High res. image (120 KB JPEG)
Fighting male fruit flies. Courtesy of the Kravitz Lab.

Gender differences in fighting styles are hardwired in fruit flies, according to a new study co-led by Edward Kravitz, a neuroscientist at Harvard Medical School. Typically, male fruit flies fend off competitors by lunging, while females favor head-butting and shoving. Kravitz and his team discovered that these fighting patterns hinge on a gene called fruitless. Swapping versions of the gene between the sexes switches the behavior. Because flies share many genes with humans, the insects are a promising tool for studying other possible genetic contributors to behavior.

Full story (no longer available)
Kravitz home page
Article abstract (from the November 14, 2006, issue of PNAS):

Synthetic Biologist Named Scientist of the Year

From the Nobel Prize award ceremony to "breakthroughs of the year," scientific achievements take center stage every December. A new honor joins the roster: Discover magazine's "Scientist of the Year." The inaugural winner is NIGMS grantee Jay Keasling of the University of California, Berkeley, who works in the area of synthetic biology, also called metabolic engineering—a field dedicated to re-engineering genomes for useful purposes. Keasling has developed tools to direct the metabolic machinery of microbes so they churn out drugs cheaply for treating malaria and other diseases. He is among a growing cadre of scientists who blend the principles of engineering and biology to find out how life works and how we can harness its operations.

Full story
Keasling home page (no longer available)