Controlled inhibition of methyltransferases using photoswitchable peptidomimetics: towards an epigenetic regulation of leukemia.
Albert, L., Xu, J., Wan, R., Srinivasan, V., Dou, Y., Vazquez, O.(2017) Chem Sci 8: 4612-4618
- PubMed: 28970883 
- DOI: https://doi.org/10.1039/c7sc00137a
- Primary Citation of Related Structures:  
5M23, 5M25 - PubMed Abstract: 
We describe a cell-permeable photoswitchable probe capable of modulating epigenetic cellular states by disruption of an essential protein-protein interaction within the MLL1 methyltransferase core complex. Our azobenzene-containing peptides selectively block the WDR5-MLL1 interaction by binding to WDR5 with high affinity ( K i = 1.25 nM). We determined the co-crystal structure of this photoswitchable peptiomimetic with WDR5 to understand the interaction at the atomic level. Importantly, the photoswitchable trans and cis conformers of the probe display a clear difference in their inhibition of MLL1. We further demonstrate that the designed photo-controllable azo-peptidomimetics affect the transcription of the MLL1-target gene Deptor, which regulates hematopoiesis and leukemogenesis, and inhibit the growth of leukemia cells. This strategy demonstrates the potential of photopharmacological inhibition of methyltransferase protein-protein interactions as a novel method for external epigenetic control, providing a new toolbox for controlling epigenetic states.
Organizational Affiliation: 
Fachbereich Chemie , Philipps-Universität Marburg , Hans-Meerwein-Strasse 4 , 35043 Marburg , Germany . Email: olalla.vazquez@staff.uni-marburg.de.