Microtubules, part of heart muscle cells’ internal “skeleton,” help determine how the heart changes shape under stress, and a common signaling pathway called the ERK pathway acts as a key controller of where the building materials for these cells’ growth are delivered inside them, a pair of new studies show. These findings, from a team at the Perelman School of Medicine at the University of Pennsylvania, point to possible new ways to address harmful heart remodeling that can be linked to heart failure.

“The molecular decision behind how a heart cell, and by extension the heart, changes in size and shape has been a mystery, even though we’ve known that heart cells do change in length and width over a person’s life in response to different conditions,” said the studies’ senior author Benjamin Prosser, Ph.D., a professor of Physiology.

“But now that we know what is doing the work and what guides it, that opens the door to targeting these mechanisms and correcting abnormal growth.”