Chemistry 2011.org
Chemistry2011.org
All About Chemistry... 2011 and beyond

Related Stories

Enlightening cancer cells with optogenetics

Harald Janovjak, Assistant Professor at IST Austria, together with Michael Grusch, Associate Professor at the Institute of Cancer Research of the Medical University of Vienna, "remote-controlled" the behaviour of cancer cells with light, as reported this week in EMBO Journal. This work is the first application of the new field of optogenetics to cancer research.

To understand the dynamics of cellular signaling, researchers need to activate and inactivate membrane receptor proteins, which serve as relays between a cell's outside and inside world. Ideally, this activation occurs on short timescales (seconds to minutes) and in targeted locations (micrometers to millimeters). However, such a high level of precision in activation cannot be achieved with current pharmacological and genetic methods. Optogenetics uses light to control cell activity, and has the advantage that light can be applied and removed precisely both in space and time. Janovjak, Grusch and colleagues re-engineered receptor tyrosine kinases (RTKs), essential cell surface receptors that sense growth factors and hormones, to be under the control of light.

When a signaling molecule binds to RTKs at the cell surface, two receptors bind to each other in a process called dimerization. This process activates signaling in the cell. Janovjak, Grusch and colleagues linked those parts of mammalian RTKs that activate cell signaling to a light-oxygen-voltage-sensing domain, a reversible light sensor that they identified in a yellow-green alga. In the engineered receptors, the dimerization step and subsequently cell signaling can now be turned on and off by light as the algal proteins sense light and bind to each other. In cancer cells, activation of the engineered receptors causes changes in cell morphology, proliferation and gene expression, characteristic of increased cancer malignancy. In blood cells, activation leads to cell sprouting, typical of the formation of new blood vessels.

The development of RTKs regulated through light-activated dimerization by Janovjak and Grusch is the first instance of light-activated dimerization of mammalian receptors. The engineered receptors can be precisely controlled by a light intensity easily achieved in microscopes and in animal models. The newly developed receptors trigger complex cellular programs in both cancer and blood endothelial cells. These cells represent new models in which behavior is under light control and which can, for instance, be used for new methods to identify drugs. In contrast to cancer, where uncontrolled activation of cell signaling results in features linked to malignancy, light activation of signaling may rescue cell survival and function in degenerative disease.

Story Source:

The above story is based on materials provided by Medical University of Vienna. Note: Materials may be edited for content and length.

Share this story with your friends!

Social Networking

Please recommend us on Facebook, Twitter and more:

Other social media tools

Global Partners
Feedback

Tell us what you think of Chemistry 2011 -- we welcome both positive and negative comments. Have any problems using the site? Questions?

About us

Chemistry2011 is an informational resource for students, educators and the self-taught in the field of chemistry. We offer resources such as course materials, chemistry department listings, activities, events, projects and more along with current news releases.

Events & Activities

Are you interested in listing an event or sharing an activity or idea? Perhaps you are coordinating an event and are in need of additional resources? Within our site you will find a variety of activities and projects your peers have previously submitted or which have been freely shared through creative commons licenses. Here are some highlights: Featured Idea 1, Featured Idea 2.

About you

Ready to get involved? The first step is to sign up by following the link: Join Here. Also don’t forget to fill out your profile including any professional designations.

Global Partners