Featured Research

from universities, journals, and other organizations

Key mechanism that drives movement in living cells discovered

Date:
August 14, 2014
Source:
National University of Singapore
Summary:
Living cell migration is regulated by the engagement of a force transmitter composed of vinculin and talin, two types of cytoskeletal protein, researchers have discovered. They showed that force-dependent vinculin binding to talin plays a critical role in mechanically connecting the actin cytoskeleton to the extracellular substrate to contribute towards cell migration.

Schematic showing the model of vinculin binding to the integrin-talin-actin complex, subsequently arresting the actin filament retrograde flow.
Credit: Image courtesy of National University of Singapore

A team of international researchers led by Professor Lim Chwee Teck, Principal Investigator, and Dr Hiroaki Hirata, Research Fellow, at the Mechanobiology Institute at the National University of Singapore (NUS), together with Professor Masahiro Sokabe from Nagoya University Graduate School of Medicine, has recently discovered that living cell migration is regulated by the engagement of a force transmitter composed of vinculin and talin, two types of cytoskeletal protein. The researchers showed that force-dependent vinculin binding to talin plays a critical role in mechanically connecting the actin cytoskeleton to the extracellular substrate to contribute towards cell migration.

This understanding of the fundamental machinery that drives living cells movement is crucial in paving the way for physiological and pathological processes in modern medicine, ranging from normal tissue development to treating cardiovascular disorders and cancer metastasis. The findings were recently published in an international journal, American Journal of Physiology -- Cell Physiology, in March 2014.

Demystifying cell movement

Individual cells possess distinct structures, known as focal adhesions, which allow them to grip onto a surface of the extracellular substrate. Inside the cell, focal adhesions are physically linked to a network of filaments, composed of a protein called actin, that form near the protruding cell membrane. These are highly dynamic and are constantly undergoing assembly and disassembly. Due to their dynamic nature, as well as the activity of protein known as myosin, the actin filaments are constantly moving inwards, towards the center of the cell.

For cells to move forward, cells have to transmit force from dynamic actin filaments to the extracellular substrate through focal adhesions. The force transmitter is engaged when force is exerted onto it. This is akin to the "automatic clutches" in vehicles. The researchers found that the force-dependent vinculin binding to talin underlies engagement of the transmitter. When the transmitter was artificially disengaged by inhibiting the vinculin-talin binding, the cells failed to move as they no longer transmit force.

It was observed that talin solely serves as slipping connection between the moving actin filament and the adhesion molecule called integrin. However, force-dependent vinculin binding to talin forms a stable integrin-talin-vinculin-actin link. The link with multiple vinculin molecules could sustain a far greater force, and this was sufficient to tether actin filaments to focal adhesions.

Although the actin filaments no longer move inwards, they are still growing near the cell membrane. This enables the membrane to protrude outwards around the growing filaments. Eventually, new adhesions form at the tip of the protrusion, allowing the cell to grab onto the substrate surface. These cycles allow the cell to move forward.

With better understanding of these processes, the researchers hope to identify new technologies and therapies targeted at encouraging or preventing cell motility.

The team has also developed a dominant-negative form of vinculin which inhibits the vinculin binding to talin, thereby inhibiting engagement of the force transmitter. If a method can be developed to introduce this dominant negative mutant specifically into cancer cells, invasion and metastasis of cancer cells could largely be suppressed.


Story Source:

The above story is based on materials provided by National University of Singapore. Note: Materials may be edited for content and length.


Journal Reference:

  1. H. Hirata, H. Tatsumi, C. T. Lim, M. Sokabe. Force-dependent vinculin binding to talin in live cells: a crucial step in anchoring the actin cytoskeleton to focal adhesions. AJP: Cell Physiology, 2014; 306 (6): C607 DOI: 10.1152/ajpcell.00122.2013

Cite This Page:

National University of Singapore. "Key mechanism that drives movement in living cells discovered." ScienceDaily. ScienceDaily, 14 August 2014. <www.sciencedaily.com/releases/2014/08/140814021500.htm>.
National University of Singapore. (2014, August 14). Key mechanism that drives movement in living cells discovered. ScienceDaily. Retrieved October 22, 2014 from www.sciencedaily.com/releases/2014/08/140814021500.htm
National University of Singapore. "Key mechanism that drives movement in living cells discovered." ScienceDaily. www.sciencedaily.com/releases/2014/08/140814021500.htm (accessed October 22, 2014).

Share This



More Plants & Animals News

Wednesday, October 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Working Mother DIY: Pumpkin Pom-Pom

Working Mother DIY: Pumpkin Pom-Pom

Working Mother (Oct. 22, 2014) How to make a pumpkin pom-pom. Video provided by Working Mother
Powered by NewsLook.com
San Diego Zoo's White Rhinos Provide Hope for the Critically Endangered Species

San Diego Zoo's White Rhinos Provide Hope for the Critically Endangered Species

Reuters - Light News Video Online (Oct. 22, 2014) The pair of rare white northern rhinos bring hope for their species as only six remain in the world. Elly Park reports. Video provided by Reuters
Powered by NewsLook.com
Raw: Bear Cub Strolls Through Oregon Drug Store

Raw: Bear Cub Strolls Through Oregon Drug Store

AP (Oct. 22, 2014) Shoppers at an Oregon drug store were surprised by a bear cub scurrying down the aisles this past weekend. (Oct. 22) Video provided by AP
Powered by NewsLook.com
Family Pleads for Pet Pig to Stay at Home

Family Pleads for Pet Pig to Stay at Home

AP (Oct. 22, 2014) The Johnson family lost their battle with the Chesterfield County, Virginia Planning Commission to allow Tucker, their pet pig, to stay in their home, but refuse to let the board keep Tucker away. (Oct. 22) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins