Ribosomes are essential molecular machines responsible for protein production, and their intricate composition has intrigued scientists for decades. But what happens when this composition changes? Kamena Kostova’s lab investigates both pathological and physiological alterations in ribosome composition. Pathological changes—triggered by damage, mutations, or assembly errors—can impair ribosome function and contribute to disease. Kostova’s team is uncovering how cells detect and degrade these defective ribosomes, while also exploring how failures in quality control lead to disease onset and progression. Her lab also investigates how physiological changes in ribosome composition that do not disrupt protein synthesis may instead play a regulatory role. Using zebrafish as a model system, the Kostova lab explores how dynamic ribosome remodeling supports embryonic development. This research reveals how the translation machinery adapts to stress, development, and disease.