About Careers MedBlog Contact us
Medindia LOGIN REGISTER
Advertisement

Study:in Planarian Flatworms Tissue Loss Triggers Regeneration

by Rukmani Krishna on September 5, 2013 at 11:23 PM
Font : A-A+

 Study:in Planarian Flatworms Tissue Loss Triggers Regeneration

Unlike humans, planarian flatworms have the remarkable ability to regrow any missing body part. Thus, they are an ideal model with which to study the molecular basis of regeneration.

Over the years scientists have learned that planarians mount recovery responses that differ depending on the severity of the injury they suffer. For example, a worm with a cut or a puncture wound reacts at the cellular and molecular levels quite differently from one that loses its head or tail. What has remained unclear, however, is just exactly how these responses are triggered.

Advertisement

Whitehead Institute Member Peter Reddien and two of his former graduate students, Michael Gaviño and Danielle Wenemoser, address this longstanding question this week in the journal eLife, revealing a fascinating interplay of signals between two wound-induced genes.

According to the work of Gavino, Wenemoser, and Reddien, regeneration initiation in planarians is regulated by the expression of the genes Smed-follistatin (or fst) and Smed-activin-1 and -2 (or act-1 and act-2), that together act like a switch. After a planarian is wounded, the type of injury determines the level fst expression——the more extreme the loss of tissue, the higher the level of fst expressed. At puncture wounds, fst expression is low, and regeneration is inhibited. However, following amputation, which results in major loss of tissue, fst levels rise and in turn inhibit Activin proteins, allowing regeneration to begin.
Advertisement

To the researchers' surprise, this interaction only affects regeneration and healing related to injury. Normal maintenance and cell turnover throughout the planarian body continue unaffected when fst is inhibited, even though these activities rely on the same neoblast cell population that creates new tissue during regeneration.

"It's a really great phenotype," says Reddien, who is also a Howard Hughes Medical Institute Early Career Scientist and an associate professor of biology at Massachusetts Institute of Technology. "It's one of the dream phenotypes—to have a defect that's regeneration-specific, where the neoblasts are working. It's just regeneration that isn't working."

Such a phenotype could be a powerful tool in the further exploration of mechanisms that control regeneration. And many questions about these mechanisms remain.

"For example, the animals know how far to grow in regeneration, so they don't make tumorous outgrowths," says Wenemoser, who is now a postdoctoral researcher at Stanford University. "There's some kind of regulation on homeostatic size, so they're not growing out all wild and crazy. There's definitely more to investigate there."

Gaviño agrees, and points out that the fst/act-1/2 switch may ultimately help scientists tease apart regeneration in other organisms, including humans.

"This regulation by activin and follistatin may be conserved in other systems," says Gaviño, who is currently a postdoctoral researcher at Univeristy of California, San Francisco. "There are a lot of hints in the scientific literature that versions of activin or follistatin or both are activated by injury and may play a role in regeneration in other animals, but pinning the role of initiating regeneration to them hasn't happened yet."

Source: Eurekalert
Advertisement

Advertisement
Advertisement

Latest Research News

Beyond the Campus: Contrasting Realities Revealed!
Sobering truth about foot travel in the United States emerges from international statistics, highlighting the prevalence of walking on the Blacksburg campus.
Astounding Link Between Darwin's Theory and Synaptic Plasticity — Discovered!
Unveiling a hidden mechanism, proteins within brain cells exhibit newfound abilities at synapses, reinforcing Darwin's theory of adaptation and diversity in the natural world.
Unlocking the Fountain of Youth: Exploring the Synergistic Power!
Combining micro-needling and cupping, two emerging and alternative techniques, in an experimental study reveals a potential synergy for skin rejuvenation.
Imminent Threat of the Next Pandemic - Disease X
Despite a decline in COVID-19 cases, the World Health Organisation (WHO) raises global concerns by warning of an "inevitable" next pandemic known as "Disease X".
Future of Reproduction: Laboratory Babies!
According to a study, a team of Japanese researchers aims to pioneer a laboratory-based method for baby development by 2028.
View All
This site uses cookies to deliver our services.By using our site, you acknowledge that you have read and understand our Cookie Policy, Privacy Policy, and our Terms of Use  Ok, Got it. Close
×

Study:in Planarian Flatworms Tissue Loss Triggers Regeneration Personalised Printable Document (PDF)

Please complete this form and we'll send you a personalised information that is requested

You may use this for your own reference or forward it to your friends.

Please use the information prudently. If you are not a medical doctor please remember to consult your healthcare provider as this information is not a substitute for professional advice.

Name *

Email Address *

Country *

Areas of Interests