6yid
Crystal structure of ULK2 in complex with SBI-0206965Crystal structure of ULK2 in complex with SBI-0206965
Structural highlights
FunctionULK2_HUMAN Serine/threonine-protein kinase involved in autophagy in response to starvation. Acts upstream of phosphatidylinositol 3-kinase PIK3C3 to regulate the formation of autophagophores, the precursors of autophagosomes. Part of regulatory feedback loops in autophagy: acts both as a downstream effector and a negative regulator of mammalian target of rapamycin complex 1 (mTORC1) via interaction with RPTOR. Activated via phosphorylation by AMPK, also acts as a negative regulator of AMPK through phosphorylation of the AMPK subunits PRKAA1, PRKAB2 and PRKAG1. May phosphorylate ATG13/KIAA0652, FRS2, FRS3 and RPTOR; however such data need additional evidences. Not involved in ammonia-induced autophagy or in autophagic response of cerebellar granule neurons (CGN) to low potassium concentration. Plays a role early in neuronal differentiation and is required for granule cell axon formation: may govern axon formation via Ras-like GTPase signaling and through regulation of the Rab5-mediated endocytic pathways within developing axons.[1] [2] [3] [4] [5] Publication Abstract from PubMedInhibition of autophagy, the major cellular recycling pathway in mammalian cells, is a promising strategy for the treatment of triple-negative breast cancer (TNBC). We previously reported SBI-0206965, a small molecule inhibitor of unc-51-like autophagy activating kinase 1 (ULK1), which is a key regulator of autophagy initiation. Herein, we describe the design, synthesis, and characterization of new dual inhibitors of ULK1 and ULK2 (ULK1/2). One inhibitor, SBP-7455 (compound 26), displayed improved binding affinity for ULK1/2 compared with SBI-0206965, potently inhibited ULK1/2 enzymatic activity in vitro and in cells, reduced the viability of TNBC cells and had oral bioavailability in mice. SBP-7455 inhibited starvation-induced autophagic flux in TNBC cells that were dependent on autophagy for survival and displayed synergistic cytotoxicity with the poly (ADP-ribose) polymerase (PARP) inhibitor olaparib against TNBC cells. These data suggest that combining ULK1/2 and PARP inhibition may have clinical utility for the treatment of TNBC. Design, Synthesis, and Characterization of an Orally Active Dual-Specific ULK1/2 Autophagy Inhibitor that Synergizes with the PARP Inhibitor Olaparib for the Treatment of Triple-Negative Breast Cancer.,Ren H, Bakas NA, Vamos M, Chaikuad A, Limpert AS, Wimer CD, Brun SN, Lambert LJ, Tautz L, Celeridad M, Sheffler DJ, Knapp S, Shaw RJ, Cosford NDP J Med Chem. 2020 Dec 10;63(23):14609-14625. doi: 10.1021/acs.jmedchem.0c00873., Epub 2020 Nov 17. PMID:33200929[6] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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