Navigation Links
Gene involved in neurodegeneration keeps clock running
Date:5/16/2013

Northwestern University scientists have shown a gene involved in neurodegenerative disease also plays a critical role in the proper function of the circadian clock.

In a study of the common fruit fly, the researchers found the gene, called Ataxin-2, keeps the clock responsible for sleeping and waking on a 24-hour rhythm. Without the gene, the rhythm of the fruit fly's sleep-wake cycle is disturbed, making waking up on a regular schedule difficult for the fly.

The discovery is particularly interesting because mutations in the human Ataxin-2 gene are known to cause a rare disorder called spinocerebellar ataxia (SCA) and also contribute to amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's disease. People with SCA suffer from sleep abnormalities before other symptoms of the disease appear.

This study linking the Ataxin-2 gene with abnormalities in the sleep-wake cycle could help pinpoint what is causing these neurodegenerative diseases as well as provide a deeper understanding of the human sleep-wake cycle.

The findings will be published May 17 in the journal Science. Ravi Allada, M.D., professor of neurobiology in the Weinberg College of Arts and Sciences, and Chunghun Lim, a postdoctoral fellow in his lab, are authors of the paper.

Period (per) is a well-studied gene in fruit flies that encodes a protein, called PER, which regulates circadian rhythm. Allada and Lim discovered that Ataxin-2 helps activate translation of PER RNA into PER protein, a key step in making the circadian clock run properly.

"It's possible that Ataxin-2's function as an activator of protein translation may be central to understanding how, when you mutate the gene and disrupt its function, it may be causing or contributing to diseases such as ALS or spinocerebellar ataxia," Allada said.

The fruit fly Drosophila melanogaster is a model organism for scientists studying the sleep-wake cycle because the fly's genes are highly conserved with the genes of humans.

"I like to say that flies sleep similarly to humans, except flies don't use pillows," said Allada, who also is associate director for Northwestern's Center for Sleep and Circadian Biology. The biological timing mechanism for all animals comes from a common ancestor hundreds of millions of years ago.

Ataxin-2 is the second gene in a little more than two years that Northwestern researchers have identified as a core gear of the circadian clock, and the two genes play similar roles.

Allada, Lim and colleagues in 2011 reported their discovery of a gene, which they dubbed "twenty-four," that plays a role in translating the PER protein, keeping the sleep-wake cycle on a 24-hour rhythm.

Allada and Lim wanted to better understand how twenty-four works, so they looked at proteins that associate with twenty-four. They found the twenty-four protein sticking to ATAXIN-2 and decided to investigate further. In their experiments, reported in Science, Allada and Lim discovered the Ataxin-2 and twenty-four genes appear to be partners in PER protein translation.

"We've really started to define a pathway that regulates the circadian clock and seems to be especially important in a specific group of neurons that governs the fly's morning wake-up," Allada said. "We saw that the molecular and behavioral consequences of losing Ataxin-2 are nearly the same as losing twenty-four."

As is the case in a mutation of the twenty-four gene, when the Ataxin-2 gene is not present, very little PER protein is found in the circadian pacemaker neurons of the brain, and the fly's sleep-wake rhythm is disturbed.


'/>"/>

Contact: Megan Fellman
fellman@northwestern.edu
847-491-3115
Northwestern University
Source:Eurekalert

Related biology news :

1. Penn biologists identify a key enzyme involved in protecting nerves from degeneration
2. Gene involved in sperm-to-egg binding is key to fertility in mammals
3. London researchers discover novel mechanism involved in key immune response
4. UCLA scientists discover how key enzyme involved in aging, cancer assembles
5. Protein involved in DNA replication, centrosome regulation linked to dwarfism, small brain size
6. 1 of the key circuits in regulating genes involved in producing blood stem cells is deciphered
7. Mechanisms involved in resistance to the bacteria Salmonella studied in a Ph.D. thesis
8. Circuitry of cells involved in immunity, autoimmune diseases exposed
9. Stay-at-home transcription factor prevents neurodegeneration
10. Researchers discover a missing link in signals contributing to neurodegeneration
11. Diversity keeps grasslands resilient to drought, climate change
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/29/2017)... , March 29, 2017  higi, the health IT ... North America , today announced a ... the acquisition of EveryMove. The new investment and acquisition ... of tools to transform population health activities through the ... data. higi collects and secures data today ...
(Date:3/24/2017)... , March 24, 2017 The Controller General ... Controller Mr. Abdulla Algeen have received the prestigious international IAIR ... Continue Reading ... ... picture) and Deputy Controller Abdulla Algeen (small picture on the right) have ...
(Date:3/23/2017)... 23, 2017 Research and Markets has announced ... & Trends - Industry Forecast to 2025" report to their ... The ... CAGR of around 8.8% over the next decade to reach approximately ... the market estimates and forecasts for all the given segments on ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... ... October 11, 2017 , ... A new study published ... frozen and fresh in vitro fertilization (IVF) transfer cycles. The multi-center ... success. , After comparing the results from the fresh and frozen transfer cohorts, ...
(Date:10/10/2017)... ... 2017 , ... San Diego-based team building and cooking events company, Lajollacooks4u, has ... The bold new look is part of a transformation to increase awareness, appeal to ... period. , It will also expand its service offering from its signature gourmet cooking ...
(Date:10/10/2017)... ... October 10, 2017 , ... For the second time in ... STEM Mentoring Award. Representatives of the FirstHand program travelled to Washington, D.C. Tuesday, ... , US2020’s mission is to change the trajectory of STEM education in America ...
(Date:10/10/2017)... Oct. 10, 2017 International research firm Parks Associates ... speak at the TMA 2017 Annual Meeting , October 11 in ... the residential home security market and how smart safety and security products ... Parks Associates: Smart ... "The residential security market ...
Breaking Biology Technology: