Featured Research

from universities, journals, and other organizations

Chemical energy influences tiny vibrations of red blood cell membranes

Date:
December 24, 2009
Source:
Massachusetts Institute of Technology
Summary:
Much like a tightly wound drum, red blood cells are in perpetual vibration. Those vibrations help the cells maintain their characteristic flattened oval or disc shape, which is critical to their ability to deform as they traverse blood vessels in the body to deliver oxygen to tissues.

Pictured is an artist's rendering of human red blood cell. Park et al. show that dynamic remodeling in the coupled membranes (lipid bilayer and two-dimensional spectrin network), powered by adenosine 5’-triphosphate (ATP), results in nonequilibrium membrane fluctuations and also maintains the biconcave shape of RBCs.
Credit: Image courtesy of Alex Jerez, YongKeun Park, Gabriel Popescu, and Subra Suresh

Much like a tightly wound drum, red blood cells are in perpetual vibration. Those vibrations help the cells maintain their characteristic flattened oval or disc shape, which is critical to their ability to deform as they traverse blood vessels in the body to deliver oxygen to tissues.

Blood disorders such as malaria, sickle cell anemia and spherocytosis interfere with those vibrations, so a better understanding of the vibrations could help researchers develop treatments for those diseases. However, the vibrations are nearly impossible to study because their amplitude is so tiny (nanometer, or billionth of a meter, scale), and they occur in just milliseconds.

A year ago, a team led by MIT Dean of Engineering Subra Suresh and Physics Professor Michael Feld, director of MIT's George R. Harrison Spectroscopy Laboratory, reported the first whole-cell glimpse of these membrane fluctuations. Now, in a paper appearing in the Proceedings of the National Academy of Sciences, they present conclusive evidence that the vibrations require energy input from ATP (adenosine triphosphate), a chemical cells use to store and transfer energy.

Previous studies examining only select locations on the cell have led to mutually contradictory results on the role of ATP in influencing cell membrane fluctuations. The MIT team used advanced spectroscopy techniques to examine the entire membrane, and found that ATP is indeed not only critical for the vibrations but it also determines the shape of the cell.

They discovered that ATP controls binding between the fatty cell membrane and the interior cellular structure, known as the spectrin network, which is necessary for the membrane vibrations to occur.

The researchers used diffraction phase microscopy, which quantitatively measures the vibrations in the cell membrane in real time. The optical phase delay, a measure of how much the light is delayed as it passes through the cell, changes as the membrane vibrates. They found that when ATP was depleted in red blood cells, vibrations decreased by 20 percent. When ATP was reintroduced, vibrations increase back to the normal level. They also found a direct correlation between the ATP-induced alteration to membrane vibrations and the length scale of the cytoskeletal structure.

This raises the possibility of developing novel diagnostics and therapeutics for blood cell disorders by determining and modulating cell activity through ATP, says Suresh.

The researchers are studying how specific proteins associated with malaria infection of red blood cells affect cell membrane stiffness and vibration, and developing sensitive new diagnostic techniques.

Funding was provided by the National Institutes of Health, Minerva Foundation, Binational Science Foundation, Imaging Science Foundation, Singapore-MIT Alliance for Research and Technology and the National Science Foundation.


Story Source:

The above story is based on materials provided by Massachusetts Institute of Technology. The original article was written by Anne Trafton, MIT News Office. Note: Materials may be edited for content and length.


Journal Reference:

  1. YongKeun Park, Catherine Best, Thorsten Auth, Nir Gov, Samuel Safran, Gabriel Popescu, Subra Suresh and Michael Feld. Metabolic remodeling of the human red blood cell membrane. Proceedings of the National Academy of Sciences, Week of Dec. 21, 2009

Cite This Page:

Massachusetts Institute of Technology. "Chemical energy influences tiny vibrations of red blood cell membranes." ScienceDaily. ScienceDaily, 24 December 2009. <www.sciencedaily.com/releases/2009/12/091222122025.htm>.
Massachusetts Institute of Technology. (2009, December 24). Chemical energy influences tiny vibrations of red blood cell membranes. ScienceDaily. Retrieved September 23, 2014 from www.sciencedaily.com/releases/2009/12/091222122025.htm
Massachusetts Institute of Technology. "Chemical energy influences tiny vibrations of red blood cell membranes." ScienceDaily. www.sciencedaily.com/releases/2009/12/091222122025.htm (accessed September 23, 2014).

Share This



More Health & Medicine News

Tuesday, September 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Ebola Costs Keep Mounting

Ebola Costs Keep Mounting

Reuters - Business Video Online (Sep. 23, 2014) The WHO has warned up to 20,000 people could be infected with Ebola over the next few weeks. As Sonia Legg reports, the implications for the West African countries suffering from the disease are huge. Video provided by Reuters
Powered by NewsLook.com
Ebola Cases Could Reach 1.4 Million Within 4 Months

Ebola Cases Could Reach 1.4 Million Within 4 Months

Newsy (Sep. 23, 2014) Health officials warn that without further intervention, the number of Ebola cases in Liberia and Sierra Leone could reach 1.4 million by January. Video provided by Newsy
Powered by NewsLook.com
WHO: Ebola Cases to Triple in Weeks Without Drastic Action

WHO: Ebola Cases to Triple in Weeks Without Drastic Action

AFP (Sep. 23, 2014) The number of Ebola infections will triple to 20,000 by November, soaring by thousands every week if efforts to stop the outbreak are not stepped up radically, the WHO warned in a study on Tuesday. Duration: 01:01 Video provided by AFP
Powered by NewsLook.com
5 Ways Men Can Prevent Most Heart Attacks

5 Ways Men Can Prevent Most Heart Attacks

Newsy (Sep. 23, 2014) No surprise here: A recent study says men can reduce their risk of heart attack by maintaining a healthy lifestyle, which includes daily exercise. Video provided by Newsy
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


Health & Medicine

Mind & Brain

Living & Well

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