LAUSR

Protein turnover (PT) refers to the continuous process of protein syn-thesis and degradation in living organisms. Proteins are one of the majordeterminantsofcellularactivitiesanddamagedproteinsneedto be replaced to maintain an efficient proteome, making PT essential for the performance of cells and tissues. The study of PT is rapidly grow-ing, especially in vivo. In this context, stable isotope metabolic labeling coupled to liquid chromatography-mass spectrometry has allowed the identification of cellular components that are extremely long-lived 1 and has provided valuable perspectives for understanding dynamic changes in complex organs such as the brain. 2 Historically, the formalisms