Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Rearranging the Cell’s Skeleton

06.02.2012
Small molecules at the cell’s membrane enable cell movement

Cell biologists at Johns Hopkins have identified key steps in how certain molecules alter a cell’s skeletal shape and drive the cell’s movement.

Results of their research, published in the December 13 issue of Science Signaling, have implications for figuring out what triggers the metastatic spread of cancer cells and wound-healing.

“Essentially we are figuring out how cells crawl,” says Takanari Inoue, Ph.D., an assistant professor of cell biology and member of the Center for Cell Dynamics in the Johns Hopkins University School of Medicine’s Institute for Basic Biomedical Sciences. “With work like ours, scientists can reveal what happens when cells move when they aren’t supposed to.”

Their new discovery highlights the role of the cell’s skeleton, or cytoskeleton, in situations where “shape shifting” can rapidly change a cell’s motion and function in response to differing environmental conditions.

When cell’s such as fibroblasts, which gather to heal wounds, move from one place to another, its cytoskeleton forms ripple-like waves or ruffles across its surface that move towards the front of the cell and down, helping pull the cell across a surface. Researchers have shown that these ruffles form when a small molecule, PIP2, appears on the inside surface of the membrane at the front edge of a cell. Until now, however, they have been unable to recreate cell ruffles simply by directing PIP2 to the cell’s front edge. Manipulations have instead led the cytoskeleton to form completely different structures, squiggles that zip across the inside of the cell like shooting stars across the sky, which the researchers call comets.

In their experiments, Inoue and his group looked for factors that determined whether a cell forms ruffles or comets. The researchers tried to create ruffles on the cell by sending in an enzyme to the cell membrane that converts another small molecule into PIP2. Using cytoskeleton building blocks marked to glow, the team used a microscope to watch the cytoskeleton assembling itself and saw that this approach caused the cytoskeleton to form comets, not the ruffles that the researchers had predicted.

The team suspected that comets formed because of a fall in levels of another small molecule used to make PIP2, PI4P.

To test this idea, the researchers tried to make ruffles on cells only by increasing PIP2 at the membrane, rather than changing the quantities of any other molecules. Using molecular tricks that hid existing PIP2 then revealed it, the researchers effectively increased the amount of available PIP2 at the membrane. This time the researchers saw ruffles.

“Now that we’ve figured out this part of how cells make ruffles, we hope to continue teasing apart the mechanism of cell movement to someday understand metastasis,” says Inoue.

“It will be interesting to manipulate other molecules at the cell surface to see what other types of cytoskeletal conformations we can control,” he says.

Tasuku Ueno and Christopher Pohlmeyer of Johns Hopkins University School of Medicine and Björn Falkenburger of the University of Washington were additional authors of the study.

This study was funded by grants from the National Institutes of Health and the Japan Society for the Promotion of Science.

*Images available upon request*

Videos:
Cell membrane ripples (ruffles): http://www.youtube.com/watch?v=FdX1UeekIFU
Comets: http://www.youtube.com/watch?v=UFYvAaq2hUM
Related Stories:
Researchers Use Light To Move Molecules: http://www.hopkinsmedicine.org/news/media/releases/hopkins_researchers_use

_light_to_move_molecules

Researchers Put Proteins Right Where They Want Them: Location Determines a Protein's Role: http://www.hopkinsmedicine.org/news/media/releases/Hopkins_Researchers_Put

_Proteins_Right_Where_They_Want_Them

Takanari Inoue on the leading edge of migrating cells: http://www.hopkinsmedicine.org/institute_basic_biomedical_sciences/about_us

/scientists/takanari_inoue.html

On the Web:
Takanari Inoue: http://www.hopkinsmedicine.org/cellbio/dept/InoueProfile.html
Department of Cell Biology: http://www.hopkinsmedicine.org/cellbio/dept/index.html

Institute for Basic Biomedical Sciences: http://www.hopkinsmedicine.org/institute_basic_biomedical_sciences/

Vanessa McMains | Newswise Science News
Further information:
http://www.jhmi.edu

Further reports about: Biomedical Biomedical Science Rearranging building block cell death skeleton

More articles from Life Sciences:

nachricht Molecular libraries for organic light-emitting diodes
24.04.2017 | Goethe-Universität Frankfurt am Main

nachricht Fine organic particles in the atmosphere are more often solid glass beads than liquid oil droplets
21.04.2017 | Max-Planck-Institut für Chemie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

Molecular libraries for organic light-emitting diodes

24.04.2017 | Life Sciences

Research sheds new light on forces that threaten sensitive coastlines

24.04.2017 | Earth Sciences

Making lightweight construction suitable for series production

24.04.2017 | Machine Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>