Featured Research

from universities, journals, and other organizations

How E. coli bacteria hijack cells' directional mechanism

Date:
March 1, 2012
Source:
UT Southwestern Medical Center
Summary:
Working in the emerging field of systems biology, researchers mathematically predicted how bacteria that cause food poisoning hijack a cell's sense of direction and then confirmed those predictions in living cells.

Dr. Neal Alto (left) and Robert Orchard are investigating how a disease-causing form of E. coli bacteria hijacks a cell’s sense of direction.
Credit: Image courtesy of UT Southwestern Medical Center

Working in the emerging field of systems biology, UT Southwestern Medical Center researchers mathematically predicted how bacteria that cause food poisoning hijack a cell's sense of direction and then confirmed those predictions in living cells.

The study proposed a new model to explain how mammalian cells establish the sense of direction necessary to move, as well as the mechanism that a disease-causing form of E. coli bacteria employ to hijack that ability. Cells need to orient themselves for several basic processes, such as keeping biochemical reactions separated in space and, in the case of immune cells, pursuing pathogens. Importantly, disruption of the cell's sense of direction often leads to human disease.

"This is a great example of scientists from different fields of research coming together to solve a complex and important biological problem," said Dr. Neal Alto, assistant professor of microbiology and senior author of the study, published Feb. 17 in Cell.

Systems biology aims to discover and understand a "circuit theory" for biology -- a set of powerful and predictive principles that will reveal how networks of biological components are wired to display the complex properties of living things. The rapidly emerging field requires experts in several scientific disciplines -- including biology, physics, mathematics and computer science -- to come together to create models of biological systems that consider both the individual parts and how these parts react to each other and to changes in their environment.

Scientists from UT Southwestern's microbiology department and the newly expanded Cecil H. and Ida Green Comprehensive Center for Molecular, Computational and Systems Biology teamed up to examine the problem collaboratively. They initially conceived a mathematical model for their hypothesis of how the cell would respond during an E. coli-induced infection and then tested their computational predictions in living cells.

"Bacteria inject protein molecules into human cells with a needle-and-syringe action," Dr. Alto said. "The human cell responds by producing a local actin-rich membrane protrusion at the spot where the bacteria attaches to the cell."

For healthy cells to move normally, these actin polymers push against a cell's membrane, protruding and propelling the cell in one direction or another. When E. coli molecules are injected, however, actin polymers rush to the site infection and help bacterial molecules both move within the cell and establish an internal site of infection.

Robert Orchard, graduate student of microbiology and the study's lead author, said: "By asking 'How does a bacterial pathogen from outside the cell regulate the host cells' actin dynamics within the cell?' we have uncovered a fundamentally new molecular circuit involved in mammalian cell polarity and bacterial infection. These findings provide new insight into the regulatory mechanisms that control both disease-causing agents and normal mammalian cell behavior."

Other UT Southwestern researchers from the Green Center involved in the work were Dr. Steven Altschuler and Dr. Lani Wu, both associate professors of pharmacology; Dr. Gürol Süel, assistant professor of pharmacology; and Mark Kittisopikul, a student in the Medical Scientist Training Program.

The National Institutes of Health, the James S. McDonnell Foundation and The Welch Foundation supported the study. The researchers also received assistance from the UT Southwestern Live Cell Imaging Facility, which is supported in part by the National Cancer Institute.


Story Source:

The above story is based on materials provided by UT Southwestern Medical Center. Note: Materials may be edited for content and length.


Journal Reference:

  1. Robert C. Orchard, Mark Kittisopikul, Steven J. Altschuler, Lani F. Wu, Gürol M. Süel, Neal M. Alto. Identification of F-actin as the Dynamic Hub in a Microbial-Induced GTPase Polarity Circuit. Cell, 2012; 148 (4): 803 DOI: 10.1016/j.cell.2011.11.063

Cite This Page:

UT Southwestern Medical Center. "How E. coli bacteria hijack cells' directional mechanism." ScienceDaily. ScienceDaily, 1 March 2012. <www.sciencedaily.com/releases/2012/03/120301084140.htm>.
UT Southwestern Medical Center. (2012, March 1). How E. coli bacteria hijack cells' directional mechanism. ScienceDaily. Retrieved October 1, 2014 from www.sciencedaily.com/releases/2012/03/120301084140.htm
UT Southwestern Medical Center. "How E. coli bacteria hijack cells' directional mechanism." ScienceDaily. www.sciencedaily.com/releases/2012/03/120301084140.htm (accessed October 1, 2014).

Share This



More Plants & Animals News

Wednesday, October 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Earth Has Lost Half Its Vertebrate Wildlife Since 1970: WWF

Earth Has Lost Half Its Vertebrate Wildlife Since 1970: WWF

Newsy (Sep. 30, 2014) — A new study published by the World Wide Fund for Nature found that more than half of the world's wildlife population has declined since 1970. Video provided by Newsy
Powered by NewsLook.com
Dolphins Might Use Earth's Magnetic Field As A GPS

Dolphins Might Use Earth's Magnetic Field As A GPS

Newsy (Sep. 30, 2014) — A study released Monday suggests dolphins might be able to sense the Earth's magnetic field and possibly use it as a means of navigation. Video provided by Newsy
Powered by NewsLook.com
How To Battle Stink Bug Season

How To Battle Stink Bug Season

Newsy (Sep. 30, 2014) — Homeowners in 33 states grapple with stink bugs moving indoors at this time of year. Here are a few tips to avoid stink bug infestations. Video provided by Newsy
Powered by NewsLook.com
California University Designs Sustainable Winery

California University Designs Sustainable Winery

Reuters - US Online Video (Sep. 27, 2014) — Amid California's worst drought in decades, scientists at UC Davis design a sustainable winery that includes a water recycling system. Vanessa Johnston reports. Video provided by Reuters
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