Featured Research

from universities, journals, and other organizations

Mixing And Matching Genes To Keep Nerve Cells Straight

Date:
June 11, 2008
Source:
Baylor College of Medicine
Summary:
With fewer than 30,000 human genes with which to work, Nature has to mix and match to generate the myriad types of neurons or nerve cells needed to assemble the brain and nervous system. Keeping this involved process on the straight and narrow requires a clever balance of promotion and inhibition, said researchers from Baylor College of Medicine.

With fewer than 30,000 human genes with which to work, Nature has to mix and match to generate the myriad types of neurons or nerve cells needed to assemble the brain and nervous system. Keeping this involved process on the straight and narrow requires a clever balance of promotion and inhibition, said researchers from Baylor College of Medicine in Houston in a report that appeared recently in the journal Developmental Cell.

"Our finding should have implications for the entire stem cell field," said Dr. Soo-Kyung Lee, assistant professor of molecular and cellular biology at BCM. "Scientists are seeking to make particular cell types using combinations of embryonic genes. They need to keeping mind that you do not just push them forward down one pathway. You must also suppress related pathways."

"During embryonic development, one needs to generate a lot of different types of neurons," said Lee, also a faculty member in the BCM Graduate School of Biomedical Sciences. "How are they being generated at the right time and place? To assemble the brain, you need all these different types of neurons. With a limited number of genes, how do you generate such a complex system?"

"We want to understand the molecular mechanisms that allow one gene to influence the formation of many neurons," she said.

They found that both promotion of one pathway and inhibition of another are required to keep the cells on the right road to cell fate determination.

"One factor does not determine cell fate," she said. It's a combination of factors or genes that together affect neuron formation.

She and her colleagues concentrated their work on the development of motor neurons in mice. Two types of nerve cells -- spinal motor neurons and V2-interneurons -- are required for motor coordination. As they become those cells, they share important regulatory factors, said Lee.

"They share a cell lineage pathway," she said. "We asked how do we generate two different lineages from one pathway?"

A cocktail of the transcription factors Isl1 and Lhx3 can cause embryonic cells to become motor neurons, she said.

"If we put only Lhx3 into the embryonic neural stem cells, they become V2-interneurons," she said. However, deleting the genes can cause the pathways to converge, resulting in hybrid cells that result in the death of the embryos.

This does not happen in Nature, she said, and they found that a gene called Hb9, expressed only in motor neurons, blocks the ability of Lhx3 to cause embryonic neural stem cells to become the V2-interneurons.

"Once you turn on the complex of Isl1 and Lhx3, then you also turn on a repressor that blocks the cells from going down the alternative pathway to becoming V2-interneurons," she said. The motor neuron fate of those cells is sealed. They found a similar repressor function in the V2-interneuron pathway.

"We think this is a delicately developed system," said Lee. "We don't think this mechanism is restricted to motor neurons."

Others who took part in this work include Seunghee Lee, Bora Lee, Kaumudi Joshi and Jae W. Lee, all of BCM and Samuel L. Pfaff of the Salk Institute in La Jolla, California.

The research was funded by the National Institute of Neurological Disorders and Stroke, PEW, March of Dimes Foundations and the Mental Retardation/Developmental Disabilities Research Center.


Story Source:

The above story is based on materials provided by Baylor College of Medicine. Note: Materials may be edited for content and length.


Cite This Page:

Baylor College of Medicine. "Mixing And Matching Genes To Keep Nerve Cells Straight." ScienceDaily. ScienceDaily, 11 June 2008. <www.sciencedaily.com/releases/2008/06/080609124611.htm>.
Baylor College of Medicine. (2008, June 11). Mixing And Matching Genes To Keep Nerve Cells Straight. ScienceDaily. Retrieved September 22, 2014 from www.sciencedaily.com/releases/2008/06/080609124611.htm
Baylor College of Medicine. "Mixing And Matching Genes To Keep Nerve Cells Straight." ScienceDaily. www.sciencedaily.com/releases/2008/06/080609124611.htm (accessed September 22, 2014).

Share This



More Health & Medicine News

Monday, September 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Liberia Pleads for Help to Fight Ebola

Liberia Pleads for Help to Fight Ebola

AP (Sep. 22, 2014) Liberia's finance minister is urging the international community to quickly follow through on pledges of cash to battle Ebola. Bodies are piling up in the capital Monrovia as the nation awaits more help. (Sept. 22) Video provided by AP
Powered by NewsLook.com
Global Ebola Aid Increasing But Critics Say It's Late

Global Ebola Aid Increasing But Critics Say It's Late

Newsy (Sep. 21, 2014) More than 100 tons of medical supplies were sent to West Africa on Saturday, but aid workers say the global response is still sluggish. Video provided by Newsy
Powered by NewsLook.com
Sierra Leone in Lockdown to Control Ebola

Sierra Leone in Lockdown to Control Ebola

AP (Sep. 21, 2014) Sierra Leone residents remained in lockdown on Saturday as part of a massive effort to confine millions of people to their homes in a bid to stem the biggest Ebola outbreak in history. (Sept. 20) Video provided by AP
Powered by NewsLook.com
Sierra Leone's Nationwide Ebola Curfew Underway

Sierra Leone's Nationwide Ebola Curfew Underway

Newsy (Sep. 20, 2014) Sierra Leone is locked down as aid workers and volunteers look for new cases of Ebola. 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:
from the past week

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