By Tina Hesman Saey
http://www.sciencenews.org/view/generic/id/347159/description/Heart_telltale
December 17, 2012
Summary: Researchers "borrowed" a protein from Dead Sea microbes and re-engineered it to make heart cells light up with every contraction. The flashing cells can offer a way to predict whether new drugs will cause heart problems in people. A protein that helps a Dead Sea microorganism harvest energy from sunlight was taken by Adam Cohen and his colleagues, and they broke the molecule so it would give off instead of absorb light under certain conditions. When the protein- called archaerhodopsin 3, or Arch for short- was placed in heart cells, it flashed dim red light when heart cells got an electrical signal to beat. When calcium enters the cell or is released from storage place inside the cell to trigger heart muscle contractions, a different version of the Arch protein blinks blue. A new field of research known as optogenetics, in which researchers use flashes of light to control the activity of nerve cells, gave way to the idea for the flashing cells. The researchers placed the red and blue twinkling proteins into human skin cells that had been reprogrammed to make stem cells, and then were altered into heart muscle cells. The cells beat in time with each other. Reprogrammed cells could be created from skin cells of people with genetic heart problems to learn more about how their condition affects heart cell function in the future. Cohen envisions using his flashing cells to screen out drugs that could cause heart problems before they go into clinical trials, because applying drugs that affect heart rate on the cells changes the way the cells beat and alters the pattern of flashes from the monitoring proteins. People someday could be able convert their own skin cells into dishes of heart cells to test how they might respond to certain drugs. Cohen and his team also engineered the monitoring proteins into the hearts of zebra fish, which are partially transparent, allowing the researchers to see how the heart cells work in an actual organism. To test for any toxic effects on the heart, drugs can be added to the water the fish swim in. Simon Atkinson, a cell biologist at the Indiana University School of Medicine in Indianapolis, said putting the proteins into zebra fish is a good way to see how cells work together in a tissue.
Relevance: This relates to our study of molecular biology, as the researchers reengineered the protein so it would give off light. We learned about biotechnology, the use of organisms to perform practical tasks for humans. The branch of biotechnology that analyzes and manipulates the genomes of organisms at the molecular level is called DNA technology. The researchers manipulated the Dead Sea microorganism's proteins so they could see it flash. This experiment could lead to discoveries in drugs, which will help humans test their responce to them . We also learned from our textbook that stem cells have the potential to differentiate into various types of cells. Skin cells were reprogrammed to make stem cells, which could become heart muscle cells.
Are there any side affects caused by adding the new protein?
ReplyDeleteThe protein doesn't alter the way the heart beats, as it simply allowed the researchers to monitor the beating of the heart cells. So no, there wouldn't be any side affects.
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