Cedars-Sinai Heart Institute researchers have found that six proteins – five more than previously thought – are responsible for cell-to-cell communication that regulates the heart and plays a role in limiting the size of heart attacks and strokes.
The smallest of these proteins directs the largest in performing its role of coordinating billions of heart cells during each heartbeat. Together, the proteins synchronize the beating heart, the researchers determined.
"We now know these proteins exist," said Robin Shaw, MD, PhD, the senior author of the study published in the journal Cell Reports. "The findings advance our understanding of cell-to-cell communication at the root of healthy heart function. When there is less cell communication, which occurs in failing hearts, chances are greater of disturbances in heart rhythm that can result in disability or death."
Until now, scientists had recognized just one protein involved in cell-to-cell communication that occurs through conduits known as "gap junctions." The Cedars-Sinai researchers identified five additional proteins that regulate the rapid flow of electrical communication signals, coordinating heart cells to produce a stable heartbeat.
"The finding of alternative translation start sites within this important group of proteins adds startling diversity to a key biological process, namely that whereby heart cells communicate with each other electrically," said Eduardo Marbán, MD, PhD, director of the Cedars-Sinai Heart Institute. "The implications are major for arrhythmias and heart failure."
Through a phenomenon called "alternative translation," the protein-making machinery in each cell can produce shorter proteins from the same gene that encodes the largest of the proteins. Biologists had known of the existence of alternative translation but had not completely understood its physiological relevance. The Cedars-Sinai research team led by Shaw has expanded the understanding of this process and continues to study the precise role of the proteins produced by it.
The researchers also have determined that a class of drugs known as "mTOR inhibitors" – those already used for immunosuppression in organ transplants – can affect alternative translation, changing the balance of proteins in hearts cells, increasing the amount of electrical coordination in the heart. The findings suggest that mTOR inhibitors can be used to prevent erratic and sometimes fatal heart rhythms.
A properly beating heart is necessary to pump blood to the brain, lungs and other organs. When arrhythmias occur in the heart's main pumping chamber, the heart can stop, resulting in sudden cardiac arrest, the most common cause of death among heart patients. Preventing arrhythmias is a top clinical priority. The possibility of using mTOR inhibitors suggests that drugs used to treat transplanted hearts could also be used to treat failing hearts.
Cell-to-cell communication occurs in all other organs. The same proteins that help heart cells communicate also play a role in brain function, bone development and insulin production in the pancreas. These proteins also affect the contraction of muscle cells within the uterus during childbirth and may potentially suppress cancer cells. The finding that mTOR inhibitors improve cell-to-cell communication indicates that this class of drugs could be useful to treat multiple disorders.
Sally Stewart | EurekAlert!
New vaccine production could improve flu shot accuracy
25.07.2017 | Duke University
Chances to treat childhood dementia
24.07.2017 | Julius-Maximilians-Universität Würzburg
Strong light-matter coupling in these semiconducting tubes may hold the key to electrically pumped lasers
Light-matter quasi-particles can be generated electrically in semiconducting carbon nanotubes. Material scientists and physicists from Heidelberg University...
Fraunhofer IPA has developed a proximity sensor made from silicone and carbon nanotubes (CNT) which detects objects and determines their position. The materials and printing process used mean that the sensor is extremely flexible, economical and can be used for large surfaces. Industry and research partners can use and further develop this innovation straight away.
At first glance, the proximity sensor appears to be nothing special: a thin, elastic layer of silicone onto which black square surfaces are printed, but these...
3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects
A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...
Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.
For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...
What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.
To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...
21.07.2017 | Event News
19.07.2017 | Event News
12.07.2017 | Event News
25.07.2017 | Physics and Astronomy
25.07.2017 | Earth Sciences
25.07.2017 | Life Sciences