Featured Research

from universities, journals, and other organizations

Key Mechanics Of Cell Membrane Fusion Revealed

Date:
April 27, 2001
Source:
University Of North Carolina School Of Medicine
Summary:
Scientists at the University of North Carolina School of Medicine in Chapel Hill have developed a new working model of cell membrane fusion.

CHAPEL HILL - Scientists at the University of North Carolina School of Medicine in Chapel Hill have developed a new working model of cell membrane fusion.

Related Articles


The model, which apparently mimics the biochemical machinery of fusion in mammalian nerve membranes, offers researchers guidance for studying the biophysics of a process fundamental to all life.

In the future, knowledge gained from this research may also be applied to human disease control. It could help enhance development of fusion-blocking agents aimed at preventing infection by HIV, influenza, Ebola and other viruses. These viruses use membrane fusion machinery to enter cells. A report of the study appears in the April 10 issue of the journal Biochemistry. It details how a group of lipids, including cholesterol, can be combined in optimal ratios so that membrane fusion can occur experimentally.

Within living cells other than bacteria are compartments that carry out different functions such as protein production and processing. And those compartments are surrounded by a lipid bilayer membrane. Fusion allows movement from one compartment to another.

"The question of concern was how does the mix of lipids in a membrane make it more or less able to fuse with another membrane," said the study's lead author Barry R. Lentz, PhD, professor of biochemistry and biophysics at UNC.

Lentz, who heads UNC's Program in Molecular and Cellular Biophysics, and his collaborators approached the question by looking at a highly "fusagenic" membrane, one that's central to nervous system functioning: the synaptic vesicle membrane. Synaptic vesicles fuse with the surface membrane of the neuron, releasing neurotransmitters that bind to the adjacent neuron.

Lentz and his colleagues have developed a fusion model for that membrane based on liposomes, lipid sacs they produced in the laboratory from pure lipids. The researchers found that the addition of the polymer polyethylene glycol forced the liposomes close together and that they could then manipulate them to make them fuse. They had already discovered that fusion between these liposomes behaved in a remarkably similar fashion to fusion reported by other scientists between biological membranes.

By mixing several pure lipids in different proportions, Lentz and Md. Emdadul Haque, PhD, of UNC and Thomas J. McIntosh, PhD of Duke University Medical Center found they could optimize fusion with a mix of lipids (cholesterol, phosphatidylcholine, sphingomyelin, phosphatydilethanolamine and phosphatidylserine) basically in the same proportions found in natural synaptic vesicle membranes.

"What we found was really mind-blowing. The optimal mix that allows membranes to fuse to the greatest extent and rupture or lose their contents to the least extent was exactly the mix Nature has designed for the synaptic vesicle in mammalian cells. Very little is known about how lipid compositions affect fusion. This report offers the first insights into how Nature has optimized membranes for fusion and should help scientists better design liposomes for delivery of drugs into cells by fusion," Lentz said

"This is one more piece of evidence for what I see as the predominant hypothesis in the field now -- that fusion in a biological membrane is a process by which lipids undergo physical changes just like they undergo in the lab," Lentz noted.

But Lentz points out that lipids are not enough to drive fusion. The chemical machine that makes those changes occur also involve proteins. "And that's what we're studying now with our liposome model," he said.

The research was supported by grants from the U.S. Public Health Service.


Story Source:

The above story is based on materials provided by University Of North Carolina School Of Medicine. Note: Materials may be edited for content and length.


Cite This Page:

University Of North Carolina School Of Medicine. "Key Mechanics Of Cell Membrane Fusion Revealed." ScienceDaily. ScienceDaily, 27 April 2001. <www.sciencedaily.com/releases/2001/04/010427071332.htm>.
University Of North Carolina School Of Medicine. (2001, April 27). Key Mechanics Of Cell Membrane Fusion Revealed. ScienceDaily. Retrieved October 23, 2014 from www.sciencedaily.com/releases/2001/04/010427071332.htm
University Of North Carolina School Of Medicine. "Key Mechanics Of Cell Membrane Fusion Revealed." ScienceDaily. www.sciencedaily.com/releases/2001/04/010427071332.htm (accessed October 23, 2014).

Share This



More Matter & Energy News

Thursday, October 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

3D Printed Instruments Make Sweet Music in Sweden

3D Printed Instruments Make Sweet Music in Sweden

Reuters - Innovations Video Online (Oct. 23, 2014) Students from Lund University's Malmo Academy of Music are believed to be the world's first band to all use 3D printed instruments. The guitar, bass guitar, keyboard and drums were built by Olaf Diegel, professor of product development, who says 3D printing allows musicians to design an instrument to their exact specifications. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Chameleon Camouflage to Give Tanks Cloaking Capabilities

Chameleon Camouflage to Give Tanks Cloaking Capabilities

Reuters - Innovations Video Online (Oct. 22, 2014) Inspired by the way a chameleon changes its colour to disguise itself; scientists in Poland want to replace traditional camouflage paint with thousands of electrochromic plates that will continuously change colour to blend with its surroundings. The first PL-01 concept tank prototype will be tested within a few years, with scientists predicting that a similar technology could even be woven into the fabric of a soldiers' clothing making them virtually invisible to the naked eye. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Jet Sales Lift Boeing Profit 18 Pct.

Jet Sales Lift Boeing Profit 18 Pct.

Reuters - Business Video Online (Oct. 22, 2014) Strong jet demand has pushed Boeing to raise its profit forecast for the third time, but analysts were disappointed by its small cash flow. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
Internet of Things Aims to Smarten Your Life

Internet of Things Aims to Smarten Your Life

AP (Oct. 22, 2014) As more and more Bluetooth-enabled devices are reaching consumers, developers are busy connecting them together as part of the Internet of Things. (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


Space & Time

Matter & Energy

Computers & Math

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