Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Three-banded panther worm debuts as a new model in the study of regeneration

25.04.2014

Closely resembling plump grains of wild rice set in motion, the three-banded panther worms swimming in disposable containers in Whitehead Institute Member Peter Reddien's lab hardly seem like the next big thing in regeneration.

And yet, these little-studied organisms possess the ability to regenerate any part of their bodies and are amenable to molecular studies in the lab, making them a valuable addition to a field keen on understanding how mechanisms controlling regeneration have evolved over millennia and how they might be activated in humans.


The lab of Whitehead Institute Member Peter Reddien is introducing the scientific community to the three-banded panther worm (Hofstenia miamia), a small organism with the ability to regenerate any missing body part. As a model, Hofstenia could help further our understanding of regeneration, how its mechanisms have evolved over millennia, and what limits regeneration in other animals, including humans. Intriguingly, Hofstenia and the planarian Schmidtea mediterranea -- long the mainstay of Reddien's research -- rely on similar molecular pathways to control regeneration despite having evolved separately over the course of roughly 550 million years.

Credit: Kathleen Mazza and Mansi Srivastava/Whitehead Institute

Four years ago, postdoctoral researcher Mansi Srivastava and Reddien, collected these intriguing animals swimming among submerged mangrove leaves and other aquatic detritus in a chilly Bermudan pond. Known scientifically as Hofstenia miamia, the worm earned its common name from the three cream-colored stripes running across its body as well as its voracious appetite for live prey.

Found in the Caribbean, Bahamas, Bermuda, and even as far away as Japan and the Red Sea, the worms were reported to be endowed with regenerative capabilities. In the 1960s, one scientist described the fact that three-banded panther worms could regrow a severed head, although no additional reports followed.

"It was a big risk for us—it was not a project where you knew it was going to work from the beginning," says Reddien, who is also an associate professor of biology at MIT and a Howard Hughes Medical Institute (HHMI) Investigator. "I had no idea how successful we'd be with culturing the animals or how successful the methods for development would be. There are all kinds of ways we could've failed on this one, but it was fun. It's the kind of science that has an adventurous spirit to it. And the organism is an even better model organism than we could have hoped for."

Reddien and Srivastava present their new model to the scientific community in the May 19th issue of the journal Current Biology.

Once the worms arrived in their new home in Cambridge, the first test was to acclimate them to lab life and determine their needs for survival. Initially, the worms were dying. The salinity of their water was off, even though it matched the pond where they were found. Hofstenia also rejected the liver that is the dietary mainstay for Reddien's other model of regeneration, the planarian (Schmidtea mediterranea). The three-banded panther worms shrank in size and some resorted to cannibalism.

Eventually, the water quality was fixed and a preferred food source was identified: sea monkeys, also known as brine shrimp. Now the worms are thriving and laying numerous eggs, enough to create an ample supply of animals for experiments.

Through a series of dissections, Reddien and Srivastava established that Hofstenia not only regenerate their heads, but, like planarians, are also able to regrow any body part. The scientists then documented the worm's transcriptome—a list of all of the genes that are transcribed in the animal—and established that RNA interference (RNAi) could be used in this animal to inhibit specific genes and unlock the molecular functions that allow regeneration.

With these tools in hand, they determined that in Hofstenia, as in planarians, Wnt signaling controls regeneration along the anterior-posterior (head-tail) axis and Bmp-Admp signaling controls regeneration along the dorsal-ventral (back-belly) axis.

If Hofstenia and planarians were phylogenetically close, such similarities would not be surprising. But after analyzing the Hofstenia transcriptome, the team determined that the three-banded panther worm and planarians are only very distantly related, a view that had been proposed based on analyses with sequences from a small number of genes.

"I find that there is no evidence, even with this large dataset, for Hofstenia to be classified with planarians, which means the last common ancestor that these two species shared existed 550 million years ago. This is the common ancestor that we, humans, also share with these species," says Srivastava, who has a background in evolutionary developmental biology and authored the Current Biology article. "The cool thing is that this raises the question of whether our common ancestor used these pathways—Wnt and Bmp signaling—to regenerate or not."

###

This work is supported by the Jane Coffin Childs Memorial Fund, Human Frontier Science Program, and the Keck Foundation.

Written by Nicole Giese Rura

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 Investigator and an Associate Professor of Biology at the Massachusetts Institute of Technology.

Full Citation:

"Whole-body acoel regeneration is controlled by Wnt and Bmp-Admp signaling"

Current Biology, May 19, 2014.

Mansi Srivastava (1), Kathleen L. Mazza-Curll (1), Josien C. van Wolfswinkel (1), and Peter W. Reddien (1).

1. Howard Hughes Medical Institute, Whitehead Institute for Biomedical Research, and Department of Biology, Massachusetts Institute of Technology, 9 Cambridge Center, Cambridge, MA 02142, USA.

Matt Fearer | Eurek Alert!

Further reports about: Biology Biomedical Medical Technology Wnt ancestor animals genes humans organism species

More articles from Life Sciences:

nachricht Perseus translates proteomics data
27.07.2016 | Max-Planck-Institut für Biochemie

nachricht Severity of enzyme deficiency central to favism
26.07.2016 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Self-assembling nano inks form conductive and transparent grids during imprint

Transparent electronics devices are present in today’s thin film displays, solar cells, and touchscreens. The future will bring flexible versions of such devices. Their production requires printable materials that are transparent and remain highly conductive even when deformed. Researchers at INM – Leibniz Institute for New Materials have combined a new self-assembling nano ink with an imprint process to create flexible conductive grids with a resolution below one micrometer.

To print the grids, an ink of gold nanowires is applied to a substrate. A structured stamp is pressed on the substrate and forces the ink into a pattern. “The...

Im Focus: The Glowing Brain

A new Fraunhofer MEVIS method conveys medical interrelationships quickly and intuitively with innovative visualization technology

On the monitor, a brain spins slowly and can be examined from every angle. Suddenly, some sections start glowing, first on the side and then the entire back of...

Im Focus: Newly discovered material property may lead to high temp superconductivity

Researchers at the U.S. Department of Energy's (DOE) Ames Laboratory have discovered an unusual property of purple bronze that may point to new ways to achieve high temperature superconductivity.

While studying purple bronze, a molybdenum oxide, researchers discovered an unconventional charge density wave on its surface.

Im Focus: Mapping electromagnetic waveforms

Munich Physicists have developed a novel electron microscope that can visualize electromagnetic fields oscillating at frequencies of billions of cycles per second.

Temporally varying electromagnetic fields are the driving force behind the whole of electronics. Their polarities can change at mind-bogglingly fast rates, and...

Im Focus: Continental tug-of-war - until the rope snaps

Breakup of continents with two speed: Continents initially stretch very slowly along the future splitting zone, but then move apart very quickly before the onset of rupture. The final speed can be up to 20 times faster than in the first, slow extension phase.phases

Present-day continents were shaped hundreds of millions of years ago as the supercontinent Pangaea broke apart. Derived from Pangaea’s main fragments Gondwana...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

GROWING IN CITIES - Interdisciplinary Perspectives on Urban Gardening

15.07.2016 | Event News

SIGGRAPH2016 Computer Graphics Interactive Techniques, 24-28 July, Anaheim, California

15.07.2016 | Event News

Partner countries of FAIR accelerator meet in Darmstadt and approve developments

11.07.2016 | Event News

 
Latest News

New study reveals where MH370 debris more likely to be found

27.07.2016 | Earth Sciences

Dirty to drinkable

27.07.2016 | Materials Sciences

Exploring one of the largest salt flats in the world

27.07.2016 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>