Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study of planarians offers insight into germ cell development

24.04.2007
The planarian is not as well known as other, more widely used subjects of scientific study - model creatures such as the fruit fly, nematode or mouse. But University of Illinois cell and developmental biology professor Phillip Newmark thinks it should be.

As it turns out, the tiny, seemingly cross-eyed flatworm is an ideal subject for the study of germ cells, precursors of eggs and sperm in all sexually reproducing species.

The planarian Newmark studies, Schmidtea mediterranea, is a tiny creature with a lot of interesting traits. Cut it in two (lengthwise or crosswise) and each piece will regenerate a new planarian, complete with brains, guts and - in most cases - gonads. Even when the planarian's brain is severed from its body, it can regenerate all that is removed, including the reproductive organs.

In a new study published this month in the Proceedings of the National Academy of Sciences, Newmark and his colleagues at the U. of I. report that planarians share some important characteristics with mammals that may help scientists tease out the mechanisms by which germ cells are formed and maintained. Newmark's team made a few discoveries related to a gene, called nanos, which was previously known to play a critical role in germ cell development in several other model organisms.

... more about:
»Newmark »germ cells »inductive »nanos »planarian

Unlike fruit flies and nematodes, which show signs of germ cell initiation in the earliest stages of their embryonic development, planarians do not generally express nanos or produce germ cells until several days after hatching. This delayed initiation of germ cell growth is called inductive specification, and is common to mammals and a number of other animals.

Graduate student Yuying Wang and the other team members were able to show that nanos is essential for inductive specification in planarians. Blocking nanos expression by means of RNA interference immediately after the planarians hatched prevented the emergence and development of germ cells. Blocking nanos in mature adults caused their ovaries and testes to disappear. And when the researchers blocked nanos expression in planarians that had had their bodies and reproductive organs detached from their brains, the planarians regenerated new bodies, but with no reproductive cells.

"This is the first time that nanos gene function has been studied in a non-traditional model organism," Newmark said. "This is important because planarians, like mammals, seem to make their germ cells by an inductive mechanism. So we're hoping that we can use the molecular biological tools available for studying planarians to get at the mechanisms that tell a cell: 'You're going to be a germ cell.' "

S. mediterranea also has the ability to reproduce asexually: It clones itself by means of fission. In looking at nanos in asexual individuals of this species, the researchers made the surprising discovery that these asexual individuals also express nanos and produce germ cells. Some other mechanism, as yet unknown, prevents these germ cells from developing into functional testes and ovaries.

"Having a simple organism that also uses inductive signaling is going to help us tease apart the more conserved mechanisms (of germ cell development and maintenance)," Newmark said. "We hope that this information will also prove informative for understanding these processes in higher organisms."

Editor's note: To reach Phillip Newmark, call 217-244-4674; e-mail:
pnewmark@uiuc.edu.

Diana Yates | University of Illinois
Further information:
http://www.news.uiuc.edu/news/07/0423germcells.html

Further reports about: Newmark germ cells inductive nanos planarian

More articles from Life Sciences:

nachricht Flow of cerebrospinal fluid regulates neural stem cell division
22.05.2018 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht Chemists at FAU successfully demonstrate imine hydrogenation with inexpensive main group metal
22.05.2018 | Friedrich-Alexander-Universität Erlangen-Nürnberg

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

Im Focus: Dozens of binaries from Milky Way's globular clusters could be detectable by LISA

Next-generation gravitational wave detector in space will complement LIGO on Earth

The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...

Im Focus: Entangled atoms shine in unison

A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.

The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...

Im Focus: Computer-Designed Customized Regenerative Heart Valves

Cardiovascular tissue engineering aims to treat heart disease with prostheses that grow and regenerate. Now, researchers from the University of Zurich, the Technical University Eindhoven and the Charité Berlin have successfully implanted regenerative heart valves, designed with the aid of computer simulations, into sheep for the first time.

Producing living tissue or organs based on human cells is one of the main research fields in regenerative medicine. Tissue engineering, which involves growing...

Im Focus: Light-induced superconductivity under high pressure

A team of scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg investigated optically-induced superconductivity in the alkali-doped fulleride K3C60under high external pressures. This study allowed, on one hand, to uniquely assess the nature of the transient state as a superconducting phase. In addition, it unveiled the possibility to induce superconductivity in K3C60 at temperatures far above the -170 degrees Celsius hypothesized previously, and rather all the way to room temperature. The paper by Cantaluppi et al has been published in Nature Physics.

Unlike ordinary metals, superconductors have the unique capability of transporting electrical currents without any loss. Nowadays, their technological...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

 
Latest News

Supersonic waves may help electronics beat the heat

18.05.2018 | Power and Electrical Engineering

Keeping a Close Eye on Ice Loss

18.05.2018 | Information Technology

CrowdWater: An App for Flood Research

18.05.2018 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>