Featured Research

from universities, journals, and other organizations

Flies On Crack: New Study Isolates Gene Mutation Responsive To Cocaine

Date:
November 25, 2004
Source:
New York University
Summary:
Researchers at the University of California, San Francisco (UCSF) and New York University have discovered a gene mutation in fruit flies that alters sensitivity to crack cocaine and also regulates their internal body clock.

Researchers at the University of California, San Francisco (UCSF) and New York University have discovered a gene mutation in fruit flies that alters sensitivity to crack cocaine and also regulates their internal body clock. The findings, reported in the December issue of Public Library of Science (PLoS) Biology, may have implications for understanding innate differences in sensitivity to cocaine in humans, potentially providing targets for development of drugs to treat or prevent addiction.

Related Articles


Headed by UCSF's Ulrike Heberlein, the research team discovered a mutation of the Drosophila LIM-only (Lmo) gene. Normal fruit flies increase their activity when exposed to low doses of crack cocaine over a one-minute period. At medium levels, fruit flies exhibit frenzied, jerky motions. At high doses, the flies become immobile. However, flies with the Lmo gene mutated were much more sensitive to crack cocaine and became immobile at much lower levels than normal fruit flies.

Heberlein's group also showed that Lmo is normally produced in the pacemaker neurons that control 24-hour--or circadian--rhythms of sleep/wake cycles in flies. Comprising about 10 cells per hemisphere, these neurons provide the fly with an internal clock, driving circadian rhythms of behavior even in the absence of light. While Lmo is found throughout the body, it is enriched in the brain. By expressing normal Lmo in over-sensitive mutants, the researchers discovered that Lmo's cocaine-related effects were localized to the circadian pacemaker neurons.

The researchers then asked if the Lmo mutations also affect the normal rhythms in circadian behavior. Subsequently, NYU's Justin Blau, an assistant professor of biology, found that many Lmo mutant flies no longer had clear rhythms of sleep/wake cycles. Together, the two sets of findings showed that the new gene modulates sensitivity to cocaine within the cells of the fruit fly's internal clock.

Previous researchers had only been able to demonstrate that cocaine enhances the mammalian brain's ability to block re-uptake of dopamine by cells in a brain region called the nucleus acumbens. But numerous experiments show this is not the whole story. The latest study by Heberlein, Blau, and their colleagues reveal a more complex neurological process.

From 400 different mutants, they identified seven with an increased response to cocaine, and for two of these, the disrupted gene was the same--Lmo. The Lmo protein, whose levels were reduced by the mutations, is known to regulate certain transcription factors during development. However, no developmental defects were detected in the loss-of-function mutants that might explain the cocaine effect. They also found that a third mutation in the same gene, previously associated with disruption in wing formation in fruit flies, increased levels of the Lmo protein and decreased response to cocaine. Thus, they concluded that Lmo appears to play a central role in regulating cocaine sensitivity.

The researchers suggested that because Lmo-related proteins are found in mammalian brains, the results may have implications for understanding innate differences in sensitivity to cocaine in humans, potentially providing targets for development of drugs to treat or prevent addiction.

"It's been established the some individuals may be predisposed to addiction," Blau added. "These findings suggest that a specific genetic make-up in humans could further explain why some individuals are more susceptible than others."


Story Source:

The above story is based on materials provided by New York University. Note: Materials may be edited for content and length.


Cite This Page:

New York University. "Flies On Crack: New Study Isolates Gene Mutation Responsive To Cocaine." ScienceDaily. ScienceDaily, 25 November 2004. <www.sciencedaily.com/releases/2004/11/041123112553.htm>.
New York University. (2004, November 25). Flies On Crack: New Study Isolates Gene Mutation Responsive To Cocaine. ScienceDaily. Retrieved December 19, 2014 from www.sciencedaily.com/releases/2004/11/041123112553.htm
New York University. "Flies On Crack: New Study Isolates Gene Mutation Responsive To Cocaine." ScienceDaily. www.sciencedaily.com/releases/2004/11/041123112553.htm (accessed December 19, 2014).

Share This


More From ScienceDaily



More Mind & Brain News

Friday, December 19, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Researchers Test Colombian Village With High Alzheimer's Rates

Researchers Test Colombian Village With High Alzheimer's Rates

AFP (Dec. 19, 2014) In Yarumal, a village in N. Colombia, Alzheimer's has ravaged a disproportionately large number of families. A genetic "curse" that may pave the way for research on how to treat the disease that claims a new victim every four seconds. Duration: 02:42 Video provided by AFP
Powered by NewsLook.com
Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Buzz60 (Dec. 19, 2014) A double-amputee makes history by becoming the first person to wear and operate two prosthetic arms using only his mind. Jen Markham has the story. Video provided by Buzz60
Powered by NewsLook.com
Prenatal Exposure To Pollution Might Increase Autism Risk

Prenatal Exposure To Pollution Might Increase Autism Risk

Newsy (Dec. 18, 2014) Harvard researchers found children whose mothers were exposed to high pollution levels in the third trimester were twice as likely to develop autism. Video provided by Newsy
Powered by NewsLook.com
Yoga Could Be As Beneficial For The Heart As Walking, Biking

Yoga Could Be As Beneficial For The Heart As Walking, Biking

Newsy (Dec. 17, 2014) Yoga can help your weight, blood pressure, cholesterol and heart just as much as biking and walking does, a new study suggests. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins