Newly discovered proteins got the beat.

• Position: The Heart

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, according to researchers at Cedars-Sinai Heart Institute, Los Angles, Calif.

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.

"We now know these proteins exist," says Robin Shaw, senior author of the study. '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 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...