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Structure of Substrate-bound SMG1-8-9 Kinase Complex Reveals Molecular Basis for Phosphorylation Specificity

Overview
Journal Elife
Specialty Biology
Date 2020 May 30
PMID 32469312
Citations 16
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Abstract

PI3K-related kinases (PIKKs) are large Serine/Threonine (Ser/Thr)-protein kinases central to the regulation of many fundamental cellular processes. PIKK family member SMG1 orchestrates progression of an RNA quality control pathway, termed nonsense-mediated mRNA decay (NMD), by phosphorylating the NMD factor UPF1. Phosphorylation of UPF1 occurs in its unstructured N- and C-terminal regions at Serine/Threonine-Glutamine (SQ) motifs. How SMG1 and other PIKKs specifically recognize SQ motifs has remained unclear. Here, we present a cryo-electron microscopy (cryo-EM) reconstruction of a human SMG1-8-9 kinase complex bound to a UPF1 phosphorylation site at an overall resolution of 2.9 Å. This structure provides the first snapshot of a human PIKK with a substrate-bound active site. Together with biochemical assays, it rationalizes how SMG1 and perhaps other PIKKs specifically phosphorylate Ser/Thr-containing motifs with a glutamine residue at position +1 and a hydrophobic residue at position -1, thus elucidating the molecular basis for phosphorylation site recognition.

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References
1.
Blackford A, Jackson S . ATM, ATR, and DNA-PK: The Trinity at the Heart of the DNA Damage Response. Mol Cell. 2017; 66(6):801-817. DOI: 10.1016/j.molcel.2017.05.015. View

2.
ONeill T, Dwyer A, Ziv Y, Chan D, Lees-Miller S, Abraham R . Utilization of oriented peptide libraries to identify substrate motifs selected by ATM. J Biol Chem. 2000; 275(30):22719-27. DOI: 10.1074/jbc.M001002200. View

3.
Gat Y, Schuller J, Lingaraju M, Weyher E, Bonneau F, Strauss M . InsP binding to PIKK kinases revealed by the cryo-EM structure of an SMG1-SMG8-SMG9 complex. Nat Struct Mol Biol. 2019; 26(12):1089-1093. DOI: 10.1038/s41594-019-0342-7. View

4.
Saxton R, Sabatini D . mTOR Signaling in Growth, Metabolism, and Disease. Cell. 2017; 168(6):960-976. PMC: 5394987. DOI: 10.1016/j.cell.2017.02.004. View

5.
Yusa K, Zhou L, Li M, Bradley A, Craig N . A hyperactive piggyBac transposase for mammalian applications. Proc Natl Acad Sci U S A. 2011; 108(4):1531-6. PMC: 3029773. DOI: 10.1073/pnas.1008322108. View