A Cancer Turn-Off

July 22, 2010

Proteins very similar to ROPs also exist in humans. In humans they are involved in wound healing, development of nerve cells in the brain, and also provide the chemical signals that tell cancer when to metastasize. In a laboratory setting, Yalovsky and his research collaborators, Prof. Yoav Henis and Dr. Joel Hirsch of TAU's departments of Neurobiology and Biochemistry, were able to use this switch mechanism in plants to reshape plant cells, grow new tissues, and respond to bacterial and viral invaders.

ROPs bind to a small molecule called GTP, which then breaks up into another molecule called GDP. It's a known concept in the plant sciences community that when bound to GDP, ROPs become inactive. With his team, Yalovsky created a second type of mutant molecule that prevents ROP proteins from binding to the GTP molecule, creating an inhibitory effect. With this knowledge, the researchers believe they are now one-step away from turning off this ROP-like switch in humans—a process which could prevent tumor growth.

“We've stumbled upon an ancient mechanism that regulates the function of these proteins, proteins which are found in both plants and humans,” says Yalovsky, explaining that this mechanism already regulates the immune response to pathogen invaders in the human body. “When these proteins are turned 'on,' they can initiate processes like cell division and growth,” says Yalovsky. “Through our genetic engineering, these proteins could be manipulated in humans to speed up tissue healing, or turned off to slow or stop the growth of tumors.”

According to the scientists, their research could also be applied in agriculture to reduce the need for chemical pesticides. The mutant molecule they devised induces plants to respond as though they are being attacked by pathogens. They then create a biological defense that protects them from infection.

In their research paper, published in the scientific journal, Current Biology, the TAU scientists describe how these mutations and mechanisms work, providing a new mechanism to control metastasis in cancer or stop the deterioration of certain nerve cells in the brain. In a broader sense, the researchers have created a long-desired platform to test the function of proteins. “It is common for plant and animal geneticists to identify proteins, but remain unaware of their functions. We now have a mechanism to test our hypotheses,” concludes Yalovsky.
 

Posted on July 22, 2010

Source: (By ISRAEL21c Staff, Israel 21c, July 20, 2010)