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 Single-stranded DNA and RNA origami go live
15.12.2017 | Wyss Institute for Biologically Inspired Engineering at Harvard

nachricht New antbird species discovered in Peru by LSU ornithologists
15.12.2017 | Louisiana State University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: First-of-its-kind chemical oscillator offers new level of molecular control

DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.

Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Engineers program tiny robots to move, think like insects

15.12.2017 | Power and Electrical Engineering

One in 5 materials chemistry papers may be wrong, study suggests

15.12.2017 | Materials Sciences

New antbird species discovered in Peru by LSU ornithologists

15.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>