Navigation Links
Zebrafish regrow fins using multiple cell types, not identical stem cells

What does it take to regenerate a limb? Biologists have long thought that organ regeneration in animals like zebrafish and salamanders involved stem cells that can generate any tissue in the body. But new research suggests that multiple cell types are needed to regrow the complete organ, at least in zebrafish.

Researchers at Washington University School of Medicine in St. Louis have shown that cells capable of regenerating a zebrafish fin do not revert to stem cells that can form any tissue. Instead, the individual cells retain their original identities and only give rise to more of their own kind.

The findings support a recent shift in how biologists understand organ regeneration in organisms such as salamanders and zebrafish. Understanding regeneration in model organisms gives hope that it may one day be possible for amputees to regrow limbs or for heart attack patients to regrow healthy heart muscle.

"Limb regeneration has long captured people's imaginations," says Stephen L. Johnson, PhD, associate professor of genetics at the School of Medicine. "Traditionally, when people have looked at how a limb regenerates, they see a group of cells forming at the amputation site and the cells all look the same. So they've imagined that these cells have lost their identities and can become anything else. Our results show that this is not the case in the zebrafish fin. And there is mounting evidence that this is not the case in the salamander limb."

The study appears online May 16 in Developmental Cell.

When a zebrafish loses its fin, a special group of cells forms on the remaining stump. These cells, which appear identical to one another, regrow the entire limb, complete with all cell types required for a complex organ. This has suggested that these cells may be "pluripotent" stem cells, capable of forming almost every tissue in the body.

To determine if this was indeed the case, Johnson and postdoctoral research associate Shu Tu, PhD, who did this work for her doctoral thesis, used genetic techniques to label individual cells in the stump with a fragment of DNA that makes the cells glow green.

When a cell divides, it copies its DNA so that each daughter cell has a complete set of genetic material. Since Johnson and Tu's label is inserted into the cell's DNA, the cells also duplicate the label and pass it on to each daughter cell. By simply observing which cells glow green, Johnson and Tu could track the subsequent daughter cells and determine what cell types they become.

For example, they saw that when they had glowing skin cells in the stump, only skin cells glowed in the regenerated limb. Likewise, when a nerve cell glowed in the stump, only nerve cells glowed in the regenerated limb. In other words, they saw no evidence that a skin cell glowing in the stump could give rise to a nerve cell glowing later in the fin's development or regeneration.

Using this technique, Johnson and Tu identified nine separate cell lineages present at the end of the stump that contribute to forming the fin's skin, nerves, pigment, blood vessels, bone and immune cells.

Johnson points out possible implications for future regenerative medicine in humans.

"This is evidence that we can't necessarily do regenerative medicine by plopping in generalized stem cells," he says. "The key may be to induce the cells that are already there to grow again. We need to understand and account for every cell lineage and then convince them to play ball together."


Contact: Julia Evangelou Strait
Washington University School of Medicine

Related biology news :

1. Digital zebrafish embryo provides the first complete developmental blueprint of a vertebrate
2. NIH grants Phylonix Phase II SBIR to develop high-throughput in vivo zebrafish assays
3. AZTI-Tecnalia coordinates a platform promoting the use of zebrafish in scientific research
4. Alzheimer cell death in Zebrafish: Demise of neurons observed live for the first time
5. Zebrafish provide a model for cancerous melanoma in humans
6. Pitt team finds molecule that regulates heart size by using zebrafish screening model
7. Drug-proof zebrafish reveal secrets of addiction
8. Zebrafish swim into drug development
9. The zebrafishs neural circuit prevents it from biting off more than it can chew
10. Zebrafish yield clues to how we process visual information
11. New research tool targets microRNA expression in zebrafish
Post Your Comments:
Related Image:
Zebrafish regrow fins using multiple cell types, not identical stem cells
(Date:5/3/2016)... , May 3, 2016  Neurotechnology, a ... the MegaMatcher Automated Biometric Identification System (ABIS) ... large-scale multi-biometric projects. MegaMatcher ABIS can process multiple ... using any combination of fingerprint, face or iris ... MegaMatcher SDK and MegaMatcher Accelerator , ...
(Date:4/19/2016)... 20, 2016 The new GEZE ... compact web-based "all-in-one" system solution for all door components. ... or the door interface with integration authorization management system, ... systems. The minimal dimensions of the access control and ... building installations offer considerable freedom of design with regard ...
(Date:3/31/2016)... , March 31, 2016   ... ("LegacyXChange" or the "Company") LegacyXChange is excited ... of its soon to be launched online site for ... ) will also provide potential shareholders a ... DNA technology to an industry that is notorious for ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... June 27, 2016   Ginkgo Bioworks , a ... engineering, was today awarded as one of the ... the world,s most innovative companies. Ginkgo Bioworks is ... the real world in the nutrition, health and ... directly with customers including Fortune 500 companies to ...
(Date:6/23/2016)... ... June 23, 2016 , ... ... its second eBook, “Clinical Trials Patient Recruitment and Retention Tips.” Partnering with experienced ... this eBook by providing practical tips, tools, and strategies for clinical researchers. , ...
(Date:6/23/2016)... Houston Methodist Willowbrook Hospital has signed ... to serve as their official health care provider. ... will provide sponsorship support, athletic training services, and ... volunteers, athletes and families. "We are ... and to bring Houston Methodist quality services and ...
(Date:6/23/2016)... ... , ... Supplyframe, the Industry Network for electronics hardware design ... Located in Pasadena, Calif., the Design Lab’s mission is to bring together inventors ... and brought to market. , The Design Lab is Supplyframe’s physical representation of ...
Breaking Biology Technology: