Featured Research

from universities, journals, and other organizations

Ancient gene gives planarians a heads-up in regeneration

Date:
May 13, 2011
Source:
Whitehead Institute for Biomedical Research
Summary:
A little-studied gene known as notum plays a key role in the planarian's regeneration decision-making process, according to scientists. At head-facing (anterior) wounds, the gene notum acts as a dimmer switch to dampen the Wnt pathway -- an ancient signaling circuit that operates in all animals -- and promote head regeneration.

A seldom-studied gene known as notum plays a key role in the planarian's regeneration decision-making process, according to Whitehead Institute scientists. Protein from this gene determines whether a head or tail will regrow at appropriate amputation sites.

Since the late 1800s, scientists have been fascinated by the planarian's amazing ability to regenerate its entire body from a small wedge of tissue. Whitehead Member Peter Reddien and former postdoctoral fellow Christian Petersen recently found that the Wnt pathway -- an ancient signaling circuit that operates in all animals -- inhibits head regeneration at wound sites in the tiny flatworms. Intriguingly, Petersen and Reddien also noticed that wounding triggers activation of a Wnt gene at injury sites that normally regenerate a head, suggesting that something else must determine whether a wound makes a head or a tail.

In a paper published in the May 13 issue of Science, authors Christian Petersen and Peter Reddien describe how the gene notum acts at head-facing (anterior) wounds as a dimmer switch to dampen the Wnt pathway and promote head regeneration. When the head or tail of a planarian is cut off, Wnt is activated. This Wnt activity turns on notum, but only at anterior-facing wounds. In a feedback loop, notum then turns Wnt down low enough that it can no longer prevent a head from forming. In tail-facing wounds, however, notum is not activated highly, a condition that promotes tail regrowth.

"These results suggest that animals 'decide' what needs to be regenerated, in part, by using cues that indicate axis direction with respect to the wound," says first author Petersen, who is a former postdoctoral fellow in the Reddien lab and currently Assistant Professor of Molecular Biosciences at Northwestern University. "It's telling us that for the head/tail decision, proper regeneration requires sensing and responding to tissue orientation at wound sites."

Petersen and Reddien are intrigued by this new role for notum. Like the Wnt signaling pathway, notum is highly conserved throughout species, from sea anenomes to fruit flies to humans, but little is known about its roles in biology. Because both notum and the Wnt signaling pathway are so evolutionarily ancient, their interaction in planarians may indicate a relationship that is important in other animals as well.

"We anticipate that this phenomenon of feedback inhibition regulating the levels of Wnt activity will be seen broadly in other biological contexts," says Reddien, who is also an Associate Professor of Biology at MIT and a Howard Hughes Medical Institute (HHMI) Early Career Scientist. "Wnt signaling is so broadly studied and important in biology, including for tissue repair and regeneration. notum isn't really on the map for the broad roles Wnt signaling plays in tissue repair, but this work demonstrates the central role it can play."

This research was supported by the National Institutes of Health (NIH), the American Cancer Society (ACS), and the Keck Foundation.

Peter Reddien's primary affiliation is with Whitehead Institute for Biomedical Research, where his laboratory is located and all his research is conducted. He is also a Howard Hughes Medical Institute Early Career Scientist and an associate professor of biology at Massachusetts Institute of Technology.


Story Source:

The above story is based on materials provided by Whitehead Institute for Biomedical Research. The original article was written by Nicole Giese. Note: Materials may be edited for content and length.


Journal Reference:

  1. Christian P. Petersen, Peter W. Reddien. Polarized notum Activation at Wounds Inhibits Wnt Function to Promote Planarian Head Regeneration. Science, 2011; 332 (6031): 852-855 DOI: 10.1126/science.1202143

Cite This Page:

Whitehead Institute for Biomedical Research. "Ancient gene gives planarians a heads-up in regeneration." ScienceDaily. ScienceDaily, 13 May 2011. <www.sciencedaily.com/releases/2011/05/110512150725.htm>.
Whitehead Institute for Biomedical Research. (2011, May 13). Ancient gene gives planarians a heads-up in regeneration. ScienceDaily. Retrieved October 22, 2014 from www.sciencedaily.com/releases/2011/05/110512150725.htm
Whitehead Institute for Biomedical Research. "Ancient gene gives planarians a heads-up in regeneration." ScienceDaily. www.sciencedaily.com/releases/2011/05/110512150725.htm (accessed October 22, 2014).

Share This



More Plants & Animals News

Wednesday, October 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Cadaver Dogs Aid Search for More Victims of Suspected Indiana Serial Killer

Cadaver Dogs Aid Search for More Victims of Suspected Indiana Serial Killer

Reuters - US Online Video (Oct. 21, 2014) Police in Gary, Indiana are using cadaver dogs to search for more victims after a suspected serial killer confessed to killing at least seven women. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
White Lion Cubs Unveiled to the Public

White Lion Cubs Unveiled to the Public

Reuters - Light News Video Online (Oct. 21, 2014) Visitors to Belgrade zoo meet a pair of three-week-old lion cubs for the first time. Tara Cleary reports. Video provided by Reuters
Powered by NewsLook.com
'Cadaver Dog' Sniffs out Human Remains

'Cadaver Dog' Sniffs out Human Remains

AP (Oct. 21, 2014) Where's a body buried? Buster's nose can often tell you. He's a cadaver dog, specially trained to find human remains and increasingly being used by law enforcement and accepted in courts. These dogs are helping solve even decades-old mysteries. (Oct. 21) Video provided by AP
Powered by NewsLook.com
White Lion Cubs Born in Belgrade Zoo

White Lion Cubs Born in Belgrade Zoo

AFP (Oct. 20, 2014) Two white lion cubs, an extremely rare subspecies of the African lion, were recently born at Belgrade Zoo. They are being bottle fed by zoo keepers after they were rejected by their mother after birth. 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


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