Regulation of eDHFR-tagged proteins with trimethoprim PROTACs

ABSTRACT: Temporal control of proteins in cells and living animals is crucial to improving the understanding of protein function in the post-genomic era. In addition, technologies that offer such control for engineered proteins could be used in therapeutic applications. Since regulation of proteins at a genomic or transcriptional level can be irreversible or a slow process, these tools may not be useful in settings where rapid temporal control is required to achieve immediate knockdown effects. PRoteolysis-TArgeting Chimeras (PROTACs) have emerged as a strategy to achieve rapid, post-translational control of protein abundance via recruitment of an E3 ligase to the target protein of interest. Here, we developed several PROTAC molecules by covalently linking the antibiotic trimethoprim (TMP) to pomalidomide, a small molecule ligand of the E3 ligase Cereblon. These molecules induce degradation of various proteins of interest (POIs) genetically fused to E. coli dihydrofolate reductase (eDHFR), the molecular target of TMP. We demonstrate that various eDHFR-tagged proteins, from fluorescent proteins to transcription factors and membrane-associated proteins, can be downregulated to 95% of maximum expression with our lead PROTAC molecule 7c. The data suggest that TMP-based PROTACs induce maximal degradation of POIs at drug concentrations that minimally affect the expression of immunomodulatory imide drug (IMiD)-sensitive neosubstrates. Finally, we show the ability to achieve multiplexed regulation with another known degron-PROTAC pair, and the formidable strength of our system for reversible protein regulation in a rodent model of metastatic cancer. Altogether, TMP PROTACs are a robust approach for selective and reversible degradation of eDHFR-tagged protein and have a strong potential for translation to in vivo models as well as dual degradation strategies with existing technologies.

INSTRUMENT(S): Q Exactive HF

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): T Cell, Lymph Node

DISEASE(S): Lymphoma

SUBMITTER: Richard Lauman  

LAB HEAD: Richard Lauman

PROVIDER: PXD045052 | Pride | 2023-12-06

REPOSITORIES: Pride