Information on proteins is critical for understanding how cells function in health and disease. But while regular proteins are easy to extract and study, it is far more difficult to gather information about membrane proteins, which are responsible for exchanging elements essential to our health, like copper, between a cell and its surrounding tissues.
Now Prof. Nir Ben-Tal and his graduate students Maya Schushan and Yariv Barkan of Tel Aviv University's Department of Biochemistry and Molecular Biology have investigated how a type of membrane protein transfers essential copper ions throughout the body. This mechanism, Schushan says, could also be responsible for how the body absorbs Cisplatin, a common chemotherapy drug used to fight cancer. In the future, this new knowledge may allow scientists to improve the way the drug is transferred throughout the body, she continues.
Their breakthrough discovery was detailed in a recent issue of PNAS (Proceedings of the National Academy of Sciences).
Cellular gatekeepers and chaperones
Most proteins are water soluble, which allows for easy treatment and study. But membrane proteins reside in the greasy membrane that surrounds a cell. If researchers attempt to study them with normal technology of solubilization in water, they are destroyed ― and can't be studied.
Copper, which is absorbed into the body through a membrane protein, is necessary to the healthy functioning of the human body. A deficiency can give rise to disease, while loss of regulation is toxic. Therefore, the cell handles copper ions with special care. One chaperone molecule delivers the copper ion to an "entrance gate" outside the cell; another chaperone then picks it up and carries it to various destinations inside the cell.
The researchers suggest that this delicate system is maintained by passing one copper ion at a time by the copper transporter, allowing for maximum cont
|Contact: George Hunka|
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