Featured Research

from universities, journals, and other organizations

How cells brace themselves for starvation

Date:
February 23, 2012
Source:
Weizmann Institute of Science
Summary:
Cells that repress their "bad time" pumps when a nutrient is abundant were much more efficient at preparing for starvation and at recovering afterward than the cells that had been genetically engineered to avoid this repression.

Sugar, cholesterol, phosphates, zinc -- a healthy body is amazingly good at keeping such vital nutrients at appropriate levels within its cells. From an engineering point of view, one all-purpose model of pump on the surface of a cell should suffice to keep these levels constant: When the concentration of a nutrient, say, sugar, drops inside the cell, the pump mechanism could simply go into higher gear until the sugar levels are back to normal. Yet strangely enough, such cells let in their nutrients using two types of pump: One is active in "good times," when a particular nutrient is abundant the cell's environment; the other is a "bad-times" pump that springs into action only when the nutrient becomes scarce. Why does the cell need this dual mechanism?

A new Weizmann Institute study, reported in Science, might provide the answer. The research was conducted in the lab of Prof. Naama Barkai of the Molecular Genetics Department by postdoctoral fellow Dr. Sagi Levy and graduate student Moshe Kafri with lab technician Miri Carmi.

It had been known for a while that when the levels of phosphate or zinc drop in the surroundings of a yeast cell, the number of "bad-times" pumps on the cell surface soars up to a hundred-fold. When phosphate or zinc becomes abundant again, the "bad-times" pumps withdraw while the "good-times" pumps return to the cell surface in large numbers. In their new study, the scientists discovered that cells which repress their "bad-time" pumps when a nutrient is abundant were much more efficient at preparing for starvation and at recovering afterwards than the cells that had been genetically engineered to avoid this repression. The conclusion: The "good-times" pumps apparently serve as a signaling mechanism that warns the yeast cell of approaching starvation. Such advance warning gives the cell more time to store up on the scarce nutrient; the thorough preparation also helps the cell to start growing faster once starvation is over.

Thus, the dual-pump system appears to be part of a regulatory mechanism that allows the cell to deal effectively with fluctuations in nutrient supply. This clever mechanism offers the cell survival advantages that could not be provided by just one type of pump.

If these findings prove to be applicable to human cells, they could explain how our bodies maintain adequate levels of various nutrients in tissues and organs. Understanding the dual-pump regulation could be crucial because it might be defective in various metabolic disorders.


Story Source:

The above story is based on materials provided by Weizmann Institute of Science. Note: Materials may be edited for content and length.


Journal Reference:

  1. S. Levy, M. Kafri, M. Carmi, N. Barkai. The Competitive Advantage of a Dual-Transporter System. Science, 2011; 334 (6061): 1408 DOI: 10.1126/science.1207154

Cite This Page:

Weizmann Institute of Science. "How cells brace themselves for starvation." ScienceDaily. ScienceDaily, 23 February 2012. <www.sciencedaily.com/releases/2012/02/120223103914.htm>.
Weizmann Institute of Science. (2012, February 23). How cells brace themselves for starvation. ScienceDaily. Retrieved April 25, 2014 from www.sciencedaily.com/releases/2012/02/120223103914.htm
Weizmann Institute of Science. "How cells brace themselves for starvation." ScienceDaily. www.sciencedaily.com/releases/2012/02/120223103914.htm (accessed April 25, 2014).

Share This



More Health & Medicine News

Friday, April 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deadly Fungus Killing Bats, Spreading in US

Deadly Fungus Killing Bats, Spreading in US

AP (Apr. 24, 2014) A disease that has killed more than six million cave-dwelling bats in the United States is on the move and wildlife biologists are worried. White Nose Syndrome, discovered in New York in 2006, has now spread to 25 states. (April 24) Video provided by AP
Powered by NewsLook.com
Companies Ramp Up Wellness to Lower Health Costs

Companies Ramp Up Wellness to Lower Health Costs

AP (Apr. 24, 2014) That little voice telling you to exercise, get in shape and get healthy is probably coming from your boss. More companies are beefing up wellness programs to try and cut down their health care costs. (April 24) Video provided by AP
Powered by NewsLook.com
Blood From World's Oldest Woman Suggests Life Limit

Blood From World's Oldest Woman Suggests Life Limit

Newsy (Apr. 24, 2014) Scientists say for the extremely elderly, their stem cells might reach a state of exhaustion. This could limit one's life span. Video provided by Newsy
Powered by NewsLook.com
FDA Wants To Ban Sales Of E-Cigarettes To Minors

FDA Wants To Ban Sales Of E-Cigarettes To Minors

Newsy (Apr. 24, 2014) The Food and Drug Administration wants to crack down on the use of e-cigarettes, banning the sale of the product to minors. 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:
from the past week

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