Featured Research

from universities, journals, and other organizations

Gene Controlling Number Of Brain Cells Pinpointed

Date:
October 5, 2009
Source:
University of North Carolina School of Medicine
Summary:
A new study suggests that a single gene, called GSK-3, controls the signals that determine how many neurons actually end up composing the brain. This has important implications for patients with neuropsychiatric illness, as links have recently been drawn between GSK-3 and schizophrenia, depression and bipolar disorder.

A new study suggests that a single gene, called GSK-3, controls the signals that determine how many neurons actually end up composing the brain.
Credit: Image courtesy of University of North Carolina School of Medicine

In populating the growing brain, neural stem cells must strike a delicate balance between two key processes – proliferation, in which the cells multiply to provide plenty of starting materials – and differentiation, in which those materials evolve into functioning neurons.

Related Articles


If the stem cells proliferate too much, they could grow out of control and produce a tumor. If they proliferate too little, there may not be enough cells to become the billions of neurons of the brain. Researchers at the University of North Carolina at Chapel Hill School of Medicine have now found that this critical balance rests in large part on a single gene, called GSK-3.

The finding suggests that GSK-3 controls the signals that determine how many neurons actually end up composing the brain. It also has important implications for patients with neuropsychiatric illness, as links have recently been drawn between GSK-3 and schizophrenia, depression and bipolar disorder.

One of the genes associated with schizophrenia appears to use GSK-3 as an intermediary to exert its effects on nerve cells. In addition, lithium, a popular treatment for bipolar disorder, acts, in part, by shutting down GSK-3. “I don’t believe anyone would have imagined that deleting GSK-3 would have such dramatic effects on neural stem cells,” said senior study author William D. Snider, M.D., professor of neurology and cell and molecular physiology, and director of the UNC Neuroscience Center. “People will have to think carefully about whether giving a drug like lithium to children could have negative effects on the underlying structure of the nervous system.”

In a study appearing online October 4th in the journal Nature Neuroscience, Snider and his colleagues created a mouse model in which both forms of the GSK-3 gene – designated alpha and beta – had been deleted. They decided to go after GSK-3 – which stands for glycogen synthase kinase 3 – because it is one of the most studied kinases or signaling molecules in all of biology.

The researchers used a “conditional knock-out” strategy to remove GSK-3 at a specific time in the development of the mouse embryo, when a type of cell called a radial progenitor cell had just been formed.

As the brain develops, neural stem cells evolve through three different stages -- neural epithelial cells, radial progenitor cells and intermediate neural precursors. The radial progenitor cells are especially important because they are thought to provide the majority of the neurons of the developing brain but also differentiate themselves to give rise to all the cellular elements of the brain. The researchers discovered that deleting GSK-3 during this second phase of development caused the radial progenitor cells to be locked in a constant state of proliferation.

“It was really quite striking,” said Snider. “Without GSK-3, these neural stem cells just keep dividing and dividing and dividing. The entire developing brain fills up with these neural stem cells that never turn into mature neurons.”

GSK-3 is known to coordinate signals for proliferation and differentiation within nerve cells through multiple “signaling pathways.” Thus, the researchers looked to see what effect deleting the molecule had on some of these pathways. They found that every one of the pathways that they studied went awry.

Snider and his colleagues now want to see if adding GSK-3 back to their genetically engineered mice can convert the proliferating stem cells into neurons, possibly resulting in three to four times as many neurons in the mutants as normal.

“I find that quite interesting because I can’t think of any other manipulation that potentially would enable you to simply dial up and down the number of neurons that are generated in the brain,” said Snider.

Funding for the studies led at UNC came from the National Institutes of Health. Study co-authors from Snider’s laboratory at UNC include lead author Woo-Yang Kim, Ph.D., postdoctoral research associate; Xinshuo Wang, graduate student and Yaohong Wu, chief technician. Researchers from the laboratory of James R. Woodgett, Ph.D. at the University of Toronto also collaborated on the project.


Story Source:

The above story is based on materials provided by University of North Carolina School of Medicine. Note: Materials may be edited for content and length.


Cite This Page:

University of North Carolina School of Medicine. "Gene Controlling Number Of Brain Cells Pinpointed." ScienceDaily. ScienceDaily, 5 October 2009. <www.sciencedaily.com/releases/2009/10/091004141221.htm>.
University of North Carolina School of Medicine. (2009, October 5). Gene Controlling Number Of Brain Cells Pinpointed. ScienceDaily. Retrieved November 26, 2014 from www.sciencedaily.com/releases/2009/10/091004141221.htm
University of North Carolina School of Medicine. "Gene Controlling Number Of Brain Cells Pinpointed." ScienceDaily. www.sciencedaily.com/releases/2009/10/091004141221.htm (accessed November 26, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Wednesday, November 26, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Pet Dogs to Be Used in Anti-Ageing Trial

Pet Dogs to Be Used in Anti-Ageing Trial

Reuters - Innovations Video Online (Nov. 26, 2014) Researchers in the United States are preparing to discover whether a drug commonly used in human organ transplants can extend the lifespan and health quality of pet dogs. Video provided by Reuters
Powered by NewsLook.com
From Popcorn To Vending Snacks: FDA Ups Calorie Count Rules

From Popcorn To Vending Snacks: FDA Ups Calorie Count Rules

Newsy (Nov. 25, 2014) The US FDA is announcing new calorie rules on Tuesday that will require everywhere from theaters to vending machines to include calorie counts. Video provided by Newsy
Powered by NewsLook.com
Daily Serving Of Yogurt Could Reduce Risk Of Type 2 Diabetes

Daily Serving Of Yogurt Could Reduce Risk Of Type 2 Diabetes

Newsy (Nov. 25, 2014) Need another reason to eat yogurt every day? Researchers now say it could reduce a person's risk of developing type 2 diabetes. Video provided by Newsy
Powered by NewsLook.com
Madagascar Working to Contain Plague Outbreak

Madagascar Working to Contain Plague Outbreak

AFP (Nov. 24, 2014) Madagascar said Monday it is trying to contain an outbreak of plague -- similar to the Black Death that swept Medieval Europe -- that has killed 40 people and is spreading to the capital Antananarivo. Duration: 00:42 Video provided by AFP
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