Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Under pressure: Mechanical stress is a key driver of cell-cell fusion, study finds

13.02.2015

Just as human relationships are a two-way street, fusion between cells requires two active partners: one to send protrusions into its neighbor, and one to hold its ground and help complete the process. Researchers have now found that one way the receiving cell plays its role is by having a key structural protein come running in response to pressure on the cell membrane, rather than waiting for chemical signals to tell it that it's needed. The study, which helps open the curtain on a process relevant to muscle formation and regeneration, fertilization, and immune response, appears in the March 9 issue of the journal Developmental Cell.

"We knew that in cell fusion, one cell attacks its fusion partner, but we didn't know what the other cell was doing," says Elizabeth Chen, Ph.D. , an associate professor of molecular biology and genetics at the Johns Hopkins University School of Medicine. "Now we know that the other cell is putting up some resistance."


Myosin (red) swarms to the site where a cell is probed.

Credit: Win Pin Ng and Sungmin Son

The merging of two cells, which is crucial to conception, development and physiology of complex organisms, was long thought to be a symmetrical process, where two cells contribute equally. But two years ago, Chen's research group showed that, in fact, one of the fusion partners initiates the process by extending fingerlike protrusions into the other partner.

For this study, Chen's group and collaborators focused on the receiving partner. Using fruit fly embryos and lab-grown fly cells that were induced to fuse, they saw that in the areas where the attacking cells drilled in, the receiving cells quickly fortified their cellular skeletons, effectively pushing back.

"We think that by stiffening its skeleton in this way, the receiving cell avoids moving away from the attacking cell, in which case fusion couldn't occur," Chen says. "The interplay of the two cells pushing against one another brings the two cell membranes into close proximity so that fusion can proceed."

But how were the cellular skeleton's building blocks, such as the protein myosin II, being summoned to the fusion site? To find out, Chen's group altered cell surface proteins that are known to relay chemical signals in the receiving cells of fly embryos.

"In most of the cells, we still saw myosin swarm to the fusion site, despite the fact that chemical signaling had been disabled," Chen says. In other words, myosin is able to sense and respond to pressure on the outside of the cell. Myosin's "mechanosensory" response was also seen when Chen's collaborators used either a tiny pipette to apply a pulling force or a tiny probe to apply a pushing force to lab-grown cells.

There is much still to learn about the cell fusion process, however. Next, Chen's group plans to examine how pressure is conveyed from the cell membrane to its skeleton and which proteins on the membrane facilitate fusion.

###

Other authors on the paper are Ji Hoon Kim, Yixin Ren, Shuo Li, Yee-Seir Kee, Shiliang Zhang and Douglas N. Robinson of The Johns Hopkins University; Win Pin Ng, Sungmin Son and Daniel A. Fletcher of the University of California, Berkeley; and Guofeng Zhang of the National Institute of Biomedical Imaging and Bioengineering.

Read the Developmental Cell article. http://www.cell.com/developmental-cell/abstract/S1534-5807%2815%2900028-3

Media Contact

Shawna Williams
shawna@jhmi.edu
410-955-8236

 @HopkinsMedicine

http://www.hopkinsmedicine.org 

Shawna Williams | EurekAlert!

More articles from Life Sciences:

nachricht Topologische Quantenchemie
21.07.2017 | Max-Planck-Institut für Chemische Physik fester Stoffe

nachricht Topological Quantum Chemistry
21.07.2017 | Max-Planck-Institut für Chemische Physik fester Stoffe

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: 3-D scanning with water

3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects

A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

Im Focus: The proton precisely weighted

What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.

To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...

Im Focus: On the way to a biological alternative

A bacterial enzyme enables reactions that open up alternatives to key industrial chemical processes

The research team of Prof. Dr. Oliver Einsle at the University of Freiburg's Institute of Biochemistry has long been exploring the functioning of nitrogenase....

Im Focus: The 1 trillion tonne iceberg

Larsen C Ice Shelf rift finally breaks through

A one trillion tonne iceberg - one of the biggest ever recorded -- has calved away from the Larsen C Ice Shelf in Antarctica, after a rift in the ice,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

The technology with a feel for feelings

12.07.2017 | Event News

 
Latest News

Ultrathin device harvests electricity from human motion

24.07.2017 | Power and Electrical Engineering

Scientists announce the quest for high-index materials

24.07.2017 | Materials Sciences

ADIR Project: Lasers Recover Valuable Materials

24.07.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>