Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Iowa State, Ames Lab researchers find three unique cell-to-cell bonds

02.11.2012
The human body has more than a trillion cells, most of them connected, cell to neighboring cells.
How, exactly, do those bonds work? What happens when a pulling force is applied to those bonds? How long before they break? Does a better understanding of all those bonds and their responses to force have implications for fighting disease?

Sanjeevi Sivasankar, an Iowa State assistant professor of physics and astronomy and an associate of the U.S. Department of Energy’s Ames Laboratory, is leading a research team that’s answering those questions as it studies the biomechanics and biophysics of the proteins that bond cells together.

The researchers discovered three types of bonds when they subjected common adhesion proteins (called cadherins) to a pulling force: ideal, catch and slip bonds. The three bonds react differently to that force: ideal bonds aren’t affected, catch bonds last longer and slip bonds don’t last as long.

The findings have just been published by the online Early Edition of the Proceedings of the National Academy of Sciences.

Sivasankar said ideal bonds – the ones that aren’t affected by the pulling force – had not been seen in any previous experiments. The researchers discovered them as they observed catch bonds transitioning to slip bonds.

“Ideal bonds are like a nanoscale shock absorber,” Sivasankar said. “They dampen all the force.”

And the others?

“Catch bonds are like a nanoscale seatbelt,” he said. “They become stronger when pulled. Slip bonds are more conventional; they weaken and break when tugged.”

In addition to Sivasankar, the researchers publishing the discovery are Sabyasachi Rakshit, an Iowa State post-doctoral research associate in physics and astronomy and an Ames Laboratory associate; Kristine Manibog and Omer Shafraz, Iowa State doctoral students in physics and astronomy and Ames Laboratory student associates; and Yunxiang Zhang, a post-doctoral research associate for the University of California, Berkeley’s California Institute for Quantitative Biosciences.

The project was supported by a $308,000 grant from the American Heart Association, a $150,000 Basil O’Connor Award from the March of Dimes Foundation and Sivasankar’s Iowa State startup funds.

The researchers made their discovery by taking single-molecule force measurements with an atomic force microscope. They coated the microscope tip and surface with cadherins, lowered the tip to the surface so bonds could form, pulled the tip back, held it and measured how long the bonds lasted under a range of constant pulling force.

The researchers propose that cell binding “is a dynamic process; cadherins tailor their adhesion in response to changes in the mechanical properties of their surrounding environment,” according to the paper.

When you cut your finger, for example, cells filling the wound might use catch bonds that resist the pulls and forces placed on the wound. As the forces go away with healing, the cells may transition to ideal bonds and then to slip bonds.

Sivasankar said problems with cell adhesion can lead to diseases, including cancers and cardiovascular problems.

And so Sivasankar said the research team is pursuing other studies of cell-to-cell bonds: “This is the beginning of a lot to be discovered about the role of these types of interactions in healthy physiology as well as diseases like cancer.”

Sanjeevi Sivasankar | EurekAlert!
Further information:
http://www.iastate.edu

More articles from Life Sciences:

nachricht Discovery of a fundamental limit to the evolution of the genetic code
03.05.2016 | Institute for Research in Biomedicine (IRB Barcelona)

nachricht Perfect imperfection
03.05.2016 | Christian-Albrechts-Universität zu Kiel

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Nuclear Pores Captured on Film

Using an ultra fast-scanning atomic force microscope, a team of researchers from the University of Basel has filmed “living” nuclear pore complexes at work for the first time. Nuclear pores are molecular machines that control the traffic entering or exiting the cell nucleus. In their article published in Nature Nanotechnology, the researchers explain how the passage of unwanted molecules is prevented by rapidly moving molecular “tentacles” inside the pore.

Using high-speed AFM, Roderick Lim, Argovia Professor at the Biozentrum and the Swiss Nanoscience Institute of the University of Basel, has not only directly...

Im Focus: 2+1 is Not Always 3 - In the microworld unity is not always strength

If a person pushes a broken-down car alone, there is a certain effect. If another person helps, the result is the sum of their efforts. If two micro-particles are pushing another microparticle, however, the resulting effect may not necessarily be the sum their efforts. A recent study published in Nature Communications, measured this odd effect that scientists call “many body.”

In the microscopic world, where the modern miniaturized machines at the new frontiers of technology operate, as long as we are in the presence of two...

Im Focus: Tiny microbots that can clean up water

Researchers from the Max Planck Institute Stuttgart have developed self-propelled tiny ‘microbots’ that can remove lead or organic pollution from contaminated water.

Working with colleagues in Barcelona and Singapore, Samuel Sánchez’s group used graphene oxide to make their microscale motors, which are able to adsorb lead...

Im Focus: ORNL researchers discover new state of water molecule

Neutron scattering and computational modeling have revealed unique and unexpected behavior of water molecules under extreme confinement that is unmatched by any known gas, liquid or solid states.

In a paper published in Physical Review Letters, researchers at the Department of Energy's Oak Ridge National Laboratory describe a new tunneling state of...

Im Focus: Bionic Lightweight Design researchers of the Alfred Wegener Institute at Hannover Messe 2016

Honeycomb structures as the basic building block for industrial applications presented using holo pyramid

Researchers of the Alfred Wegener Institute (AWI) will introduce their latest developments in the field of bionic lightweight design at Hannover Messe from 25...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

The “AC21 International Forum 2016” is About to Begin

27.04.2016 | Event News

Soft switching combines efficiency and improved electro-magnetic compatibility

15.04.2016 | Event News

Grid-Supportive Buildings Give Boost to Renewable Energy Integration

12.04.2016 | Event News

 
Latest News

Quantum Logical Operations Realized with Single Photons

03.05.2016 | Physics and Astronomy

Discovery of a fundamental limit to the evolution of the genetic code

03.05.2016 | Life Sciences

Cavitation aggressive intensity greatly enhanced using pressure at bubble collapse region

03.05.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>