Featured Research

from universities, journals, and other organizations

New Model For Embryonic Limb Development Revealed

Date:
May 1, 2008
Source:
University of Southern California
Summary:
Researchers have found a new model to explain how signals between cells in the embryo control limb development. They discovered that secreted growth factors at the distal tip of the embryonic limb act as instructive molecules that control the pattern of bones along the length of the limb in an animal model.

A study led by a researcher at the University of Southern California has found a new model to explain how signals between cells in the embryo control limb development.

Related Articles


The study, which will be published in the May issue of the journal Nature and now available online, found that secreted growth factors at the distal tip of the embryonic limb act as instructive molecules that control the pattern of bones along the length of the limb in an animal model.

"For many years, biologists have been fascinated by the question of how the skeleton forms during embryonic development so that all the bones are in the proper place and the proper shapes, says Francesca V. Mariani, Ph.D., assistant professor at the Keck School of Medicine of USC and one of the lead authors of the study. "Much of the research has been focused on the limb as a framework for understanding the basic steps of skeletal development."

Researchers have long known that the apical ectodermal ridge (AER), a special epithelial structure at the distal tip of the embryonic limb, is important for limb outgrowth. Less clear has been the role of the fibroblast growth factor (FGF) family that emanate from the AER, Mariani says.

"Our study shows that FGFs are not just important for limb outgrowth but act as instructive molecules that control the pattern of bones along the length of the mouse limb," she says. "The study of limb development may help contribute to the further understanding of how limbs might regenerate."

Mariani, a recent recruit to the Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research at USC conducted the research while at the University of California, San Francisco. She worked in collaboration with Gail Martin, a pioneer in embryonic stem cell research.

Researchers concluded that FGFs act as instructive molecules by examining the expression of a gene called Meis1 found at the proximal portion of the developing limb bud. The new model presented in the study proposes that proximal and distal domains are specified by two opposing signals: a proximal signal from the flank and a distal signal from the AER, and that a middle domain forms as an interaction between the two domains or two signals.

The model proposed by the study is provocative because it is similar to a model proposed for limb regeneration in amphibians, Mariani says. The findings could have a significant impact on future study in this area.

"This exciting study proposes a new model to explain how signals between cells in the embryo control the growth and formation of the mammalian limb," says Martin Pera, Ph.D., director of the Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research at USC. "Tissue repair processes in the adult often use the same cellular programs in building the embryo, so these new findings may provide important clues to guide future treatment of injuries using cell-based therapies."

The study was supported by a grant from the National Institutes of Health awarded to Gail Martin. Francesca Mariani was supported by postdoctoral grants from the NIH and the American Heart Association.

Reference: Francesca V. Mariani, Christina P. Ahn & Gail R. Martin. "Genetic evidence that FGFs have an instructive role in limb proximal-distal patterning," Nature (2008). Doi:10.1038/nature06876


Story Source:

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


Cite This Page:

University of Southern California. "New Model For Embryonic Limb Development Revealed." ScienceDaily. ScienceDaily, 1 May 2008. <www.sciencedaily.com/releases/2008/04/080430134243.htm>.
University of Southern California. (2008, May 1). New Model For Embryonic Limb Development Revealed. ScienceDaily. Retrieved October 26, 2014 from www.sciencedaily.com/releases/2008/04/080430134243.htm
University of Southern California. "New Model For Embryonic Limb Development Revealed." ScienceDaily. www.sciencedaily.com/releases/2008/04/080430134243.htm (accessed October 26, 2014).

Share This



More Plants & Animals News

Sunday, October 26, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Reuters - Innovations Video Online (Oct. 24, 2014) Miniature deep sea animals discovered off the Australian coast almost three decades ago are puzzling scientists, who say the organisms have proved impossible to categorise. Academics at the Natural History of Denmark have appealed to the world scientific community for help, saying that further information on Dendrogramma enigmatica and Dendrogramma discoides could answer key evolutionary questions. Jim Drury has more. Video provided by Reuters
Powered by NewsLook.com
Black Bear Cub Goes Sunday Shopping

Black Bear Cub Goes Sunday Shopping

Reuters - Light News Video Online (Oct. 23, 2014) Price check on honey? Bear cub startles Oregon drugstore shoppers. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Dances With Wolves in China's Wild West

Dances With Wolves in China's Wild West

AFP (Oct. 23, 2014) One man is on a mission to boost the population of wolves in China's violence-wracked far west. The animal - symbol of the Uighur minority there - is under threat with a massive human resettlement program in the region. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com
Breakfast Debate: To Eat Or Not To Eat?

Breakfast Debate: To Eat Or Not To Eat?

Newsy (Oct. 23, 2014) Conflicting studies published in the same week re-ignited the debate over whether we should be eating breakfast. 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


Plants & Animals

Earth & Climate

Fossils & Ruins

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