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The HisRS-like domain of GCN2 is a pseudoenzyme that can bind uncharged tRNA - HX-MS Data

ABSTRACT: GCN2 is a stress response kinase that phosphorylates the translation initiation factor eIF2to inhibit general protein synthesis when activated by uncharged tRNA and stalled ribosomes. The presence of a HisRS-like domain in GCN2, normally associated with the ability to bind and aminoacylate tRNAs, led to the hypothesis that eIF2 kinase activity is regulated by the direct binding of this domain to uncharged tRNA. Here we solved the structure of the HisRS-like domain in the context of full-length GCN2 by cryoEM. Structure and function analysis shows the HisRS-like domain of GCN2 has lost tRNA charging, ATP binding, and histidine binding activity but retains the ability to bind tRNA. Hydrogen deuterium exchange mass spectrometry (HX-MS), site-directed mutagenesis and computational docking experiments support a tRNA binding model that overlaps with but is partially shifted from that employed by bona fide HisRS enzymes. These results demonstrate that the HisRS-like domain of GCN2 is a pseudoenzyme and advance our understanding of GCN2 regulation and function.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Homo Sapiens (human)

SUBMITTER: Frantisek Filandr

LAB HEAD: David Schriemer

PROVIDER: PXD049090 | Pride | 2024-02-01

REPOSITORIES: Pride

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			Action	DRS
	2023-09-20-hGCN2-DIA-bin-file-375-911mz.csv	Csv
	2023-09-21-hCGN2-Full-Mapping.ms2.csv	Csv
	2023-09-21-hGCN2-AutoHX-1hour-timepoint-processing-parameters.xml	Xml
	2023-09-21-hGCN2-PIPE-mapping-processing-parameters.xml	Xml
	20230920_140441_Prot-mapping-125ulmin-Rep1.raw	Raw

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