Navigation Links
Dividing cells 'feel' their way out of warp
Date:9/10/2009

Every moment, millions of a body's cells flawlessly divvy up their genes and pinch perfectly in half to form two identical progeny for the replenishment of tissues and organs even as they collide, get stuck, and squeeze through infinitesimally small spaces that distort their shapes.

Now Johns Hopkins scientists, working with the simplest of organisms, have discovered the molecular sensor that lets cells not only "feel" changes to their neat shapes, but also to remodel themselves back into ready-to-split symmetry. In a study published September 15 in Current Biology, the researchers show that two force-sensitive proteins accumulate at the sites of cell-shape disturbances and cooperate first to sense the changes and then to resculpt the cells. The proteins myosin II and cortexillin I monitor and correct shape changes in order to ensure smooth division.

"What we found is an exquisitely tuned mechanosensory system that keeps the cells shipshape so they can divide properly," says Douglas N. Robinson, Ph.D., an associate professor of Cell Biology, Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine.

Faulty cell division can put organisms, including people, on the pathway to diseases such as cancer, Robinson notes, and a better understanding of how cells respond to mechanical stress on their shapes could present new targets for both diagnosing and treating such diseases.

Working with hardy, single-celled protozoa that move and divide similarly to human cells, the scientists watched through microscopes while they deformed the cells' shapes with a tiny instrument that, like a soda straw, sucks in on the cell surface and creates distorted shapes.

"This particular method, based on a very old principle that dates back to Archimedes, enables us to deform cells without killing them, much in the same way that natural processes in the body constantly assault them, Robinson says."

Once the cells were warped, the scientists monitored the movements of fluorescent-tagged myosin II and cortexillin I. Myosin, which normally accumulates in the middles of cells during division to help power that process, collected instead at the sites of disturbances made by the micropipette. Also amassing with myosin was cortexillin I, a so-called actin-crosslinking protein that, like glue, holds the toothpick-like filaments of a cell's housing together.

In the experiments, as soon as the two proteins accumulated to a certain level, the cells contracted, escaping the pipettes and assuming their original shapes. After the cells righted themselves, the proteins realigned along the cells' midlines and pinched to divide symmetrically into two daughter cells.

The researchers repeated the experiment using cells engineered to lack myosin II and then again with cells lacking cortexillin I. They discovered that cortexillin I responded to deformations except when myosin II was removed, and myosin II responded to deformations except when cortexillin I was removed.

"It's clear that the two need each other to operate as a cellular mechanosensor," Robinson says.


'/>"/>

Contact: Maryalice Yakutchik
myakutc1@jhmi.edu
443-287-2251
Johns Hopkins Medical Institutions
Source:Eurekalert  

Related biology news :

1. Carbon nanotubes could make efficient solar cells
2. Size of fat cells and waist size predict type 2 diabetes in women
3. Pandemic flu can infect cells deep in the lungs, says new research
4. Individual cells isolated from biological clock can keep daily time, but are unreliable
5. Researchers find first evidence of virus in malignant prostate cells
6. Liposuction leftovers easily converted to IPS cells, Stanford study shows
7. Making more efficient fuel cells
8. UT Southwestern researchers examine mechanisms that help cancer cells proliferate
9. Lower-cost solar cells to be printed like newspaper, painted on rooftops
10. Glow-in-the-dark red blood cells made from human stem cells
11. When cells run out of fuel
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Dividing cells 'feel' their way out of warp
(Date:2/7/2017)... 2017   MedNet Solutions , an innovative SaaS-based ... clinical research, is pleased to announce that the latest ... highly flexible and award winning eClinical solution, is now ... is a proven Software-as-a-Service (SaaS) clinical research technology ... but also delivers an entire suite of eClinical tools ...
(Date:2/7/2017)... 2017 Ipsidy Inc. ( www.ipsidy.com ... IDGS], ("Ipsidy" or the "Company") a provider of secure, ... is pleased to announce the following changes as part ... January 31, 2017, Philip D. Beck was ... President.  An experienced payment industry professional and public company ...
(Date:2/3/2017)... , Feb. 3, 2017  Texas Biomedical Research Institute ... Larry Schlesinger as the Institute,s new President ... Biomed effective May 31, 2017. He is currently the Chair ... of the Center for Microbial Interface Biology at Ohio State ... as the new President and CEO of Texas Biomed," said ...
Breaking Biology News(10 mins):
(Date:2/15/2017)...  Trianni, Inc. („TRIANNI") gab heute bekannt, man ... über die Verwendung der The Trianni Mouse unterschrieben, ... Entdeckung monoklonaler Antikörper. Die Trianni Plattform ... das Janssen den Zugang zu einer ... für die schelle Isolierung vollständig menschlicher Therapeutika optimiert ...
(Date:2/15/2017)... 2017  Vanda Pharmaceuticals Inc. (Vanda) (NASDAQ: VNDA), ... fourth quarter and full year ended December 31, ... for Vanda as we continued to demonstrate strong ... exclusivity for Fanapt," said Mihael H. Polymeropoulos, M.D., ... pipeline with important 2017 milestones underscores Vanda,s commitment ...
(Date:2/15/2017)... Feb. 15, 2017 Windtree Therapeutics, Inc. (Nasdaq: ... developing aerosolized KL4 surfactant therapies for respiratory diseases, will ... presentation) at 8:00 AM EST on Thursday, February 16, ... clinical program, the recently announced closing of a $10.5 ... To participate in the live call and ...
(Date:2/15/2017)... ... February 15, 2017 , ... Diameter Health ... Diameter Health technology in the hands of Lantana analysts. The high-performance platform of ... and public health entities – all those mining value from clinical data – ...
Breaking Biology Technology: