Most people think of fibrous and muscle-rich foods when they hear the word protein. In fact, every cell of the body makes proteins, which will carry out all of its many functions. Scientists are focusing on proteins — in cells and foods and fossils — to better understand how the body functions.

Researchers edited a gene that causes heart failure in newly fertilized eggs (left). Four-celled (center) and five-day-old embryos (right) look normal.

An artist’s rendering of nerve cells in the brain. A mild head trauma can cause temporary swelling in parts of those cells.