E3 ligase Ligand 16 is primarily utilized in the field of targeted protein degradation, a cutting-edge approach in drug discovery and therapeutic development. It serves as a key component in the design of PROTACs (Proteolysis-Targeting Chimeras), which are bifunctional molecules that recruit E3 ubiquitin ligases to specific target proteins, marking them for degradation by the proteasome. This ligand is particularly valuable for its ability to bind selectively to E3 ligases, enabling the precise degradation of disease-causing proteins, such as those involved in cancer, neurodegenerative disorders, and other pathological conditions. Its application extends to research tools for studying protein function and validating drug targets, offering a powerful strategy for addressing previously "undruggable" proteins.