Navigation Links
How cells brace themselves for starvation

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 in 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-times" 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.


Contact: Yivsam Azgad
Weizmann Institute of Science

Related biology news :

1. Live from the thymus: T-cells on the move
2. Synthetic protein amplifies genes needed for stem cells
3. Exercise triggers stem cells in muscle
4. Human immune cells react sensitively to stress
5. Lungs clothed in fresh cells offer new hope for transplant patients
6. New technology allows scientists to watch cancer cells in action at unprecedented resolution
7. Grape seed extract kills head and neck cancer cells, leaves healthy cells unharmed
8. Berkeley Lab researchers discover critical rotational motion in cells
9. Saving the snow leopard with stem cells
10. UCSF team uncovers how immune cells move against invaders
11. Quantitative imaging application to gut and ear cells are reported in 2 Nature papers
Post Your Comments:
(Date:11/16/2015)... , Nov 16, 2015  Synaptics Inc. ... human interface solutions, today announced expansion of its ... ™ touch controller and display driver integration ... of smartphones. These new TDDI products add to ... (HD resolution), TD4302 (WQHD resolution), and TD4322 (FHD ...
(Date:11/12/2015)... 12, 2015  Arxspan has entered into an ... Harvard for use of its ArxLab cloud-based suite ... The partnership will support the institute,s efforts to ... research information internally and with external collaborators. The ... managing the Institute,s electronic laboratory notebook, compound and ...
(Date:11/11/2015)... MedNet Solutions , an innovative SaaS-based eClinical technology company that ... announce that it will be a Sponsor of the ... held November 17-19 in Hamburg , Germany.  ... iMedNet , MedNet,s easy-to-use, proven and affordable eClinical ... able to deliver time and cost savings of up to ...
Breaking Biology News(10 mins):
(Date:11/27/2015)... /PRNewswire/--  Mallinckrodt plc (NYSE: MNK ), a ... closed the sale of its global contrast media and ... in a transaction valued at approximately $270 million. The ... total of approximately 1,000 employees spread across the globe, ... area. This entire workforce and the manufacturing ...
(Date:11/25/2015)... PUNE, India , November 26, 2015 /PRNewswire/ ... The Global Biobanking Market 2016 - 2020 ... biobanks by maintaining integrity and quality in long-term ... and enabling long-term cost-effectiveness. Automation minimizes manual errors ... improves the technical efficiency. Further, it plays a ...
(Date:11/25/2015)... SAN DIEGO , Nov. 25, 2015  Neurocrine ... Kevin Gorman , President and CEO of Neurocrine ... Jaffray Healthcare Conference in New York ... encouraged to visit the website approximately 5 minutes prior ... software.  A replay of the presentation will be available ...
(Date:11/25/2015)... ... November 25, 2015 , ... ... were featured on AngelList early in their initial angel funding process. Now, they ... for individuals looking to make early stage investments in the microbiome space. ...
Breaking Biology Technology: