Dilson Rassier Publishes Muscle Discovery in Nature Communications

Muscle discovery may lead to better drugs

The smallest constituents of muscles, myosin and actin, may be targeted to contribute to more effective treatment methods against heart and muscle diseases, say a group of international researchers at McGill University and Linnaeus University.

The question of what happens at the molecular level inside our muscles when they are activated has long eluded researchers. In muscles, there are billions of small proteins called myosin and actin. Individually, their size is only one hundred thousandth of a millimeter but these microscopic units create kinetic energy by converting cell fuel into, among other things, phosphate. But exactly how this is done has long been a mystery until now.

“We have mapped how phosphate, the substance that forms when muscles are activated, behaves when it is released from the myosin during muscle contractions,” says Dilson Rassier, Dean of Faculty of Education and lead author of the study. “The phosphate moves in a different way than previously thought and makes several 'breaks' in and on the myosin.”

“Our results are of great potential importance for treating serious diseases in which myosin plays a central role. This applies to serious diseases of the heart and body muscles, to the spread of cancer cells to new tumors and the invasion of human red blood cells by malaria parasites,” says study co-author Alf Månsson, a professor of physiology at Linnaeus University.

"Multistep orthophosphate release tunes actomyosin energy transduction” by Luisa Moretto et al. was published in Nature Communications.