Adenosine-Binding Motif Mimicry and Cellular Effects of a Thieno[2,3-D]Pyrimidine-Based Chemical Inhibitor of Atypical Protein Kinase C Isozymes.Kjaer, S., Linch, M., Purkiss, A., Kostelecky, B., Knowles, P.P., Rosse, C., Riou, P., Soudy, C., Kaye, S., Patel, B., Soriano, E., Murray-Rust, J., Barton, C., Dillon, C., Roffey, J., Parker, P.J., Mcdonald, N.Q.
(2013) Biochem.J. 451: 329
- PubMed: 23418854
- DOI: 10.1042/BJ20121871
- PubMed Abstract:
The aPKC [atypical PKC (protein kinase C)] isoforms ι and ζ play crucial roles in the formation and maintenance of cell polarity and represent attractive anti-oncogenic drug targets in Ras-dependent tumours. To date, few isoform-specific chemical bio ...
The aPKC [atypical PKC (protein kinase C)] isoforms ι and ζ play crucial roles in the formation and maintenance of cell polarity and represent attractive anti-oncogenic drug targets in Ras-dependent tumours. To date, few isoform-specific chemical biology tools are available to inhibit aPKC catalytic activity. In the present paper, we describe the identification and functional characterization of potent and selective thieno[2,3-d]pyrimidine-based chemical inhibitors of aPKCs. A crystal structure of human PKCι kinase domain bound to a representative compound, CRT0066854, reveals the basis for potent and selective chemical inhibition. Furthermore, CRT0066854 displaces a crucial Asn-Phe-Asp motif that is part of the adenosine-binding pocket and engages an acidic patch used by arginine-rich PKC substrates. We show that CRT0066854 inhibits the LLGL2 (lethal giant larvae 2) phosphorylation in cell lines and exhibits phenotypic effects in a range of cell-based assays. We conclude that this compound can be used as a chemical tool to modulate aPKC activity in vitro and in vivo and may guide the search for further aPKC-selective inhibitors.
Structural Biology, Cancer Research UK, 44 Lincoln's Inn Fields, London WC2A 3LY, UK.