CRBNdependent

CRBNdependent is a term used in molecular biology to describe processes or interactions that rely on the presence and function of the CRBN protein. CRBN, which stands for Cereblon, is a substrate receptor for the CUL4-RBX1-DDB1-CRBN (CRL4^CRBN) E3 ubiquitin ligase complex. This complex plays a crucial role in the ubiquitin-proteasome system, a fundamental cellular pathway responsible for protein degradation.

The CRL4^CRBN complex targets specific proteins for ubiquitination, marking them for destruction by the proteasome. CRBN's ability to bind to certain molecules, such as thalidomide and its analogs, is central to its function. When CRBN binds to these molecules, it alters its substrate specificity, leading to the ubiquitination and degradation of proteins that would not normally be targeted. This mechanism has been exploited in the development of novel therapeutics, particularly immunomodulatory drugs (IMiDs) used in treating certain cancers. Therefore, a process described as CRBNdependent implies that the activity of the CRL4^CRBN E3 ligase, and specifically CRBN's role in substrate recognition, is essential for that process to occur. This can include protein degradation pathways, cellular signaling events influenced by protein turnover, and therapeutic responses mediated by CRBN-binding drugs.