Dataset Information

O-GlcNAcylation controls pro-fibrotic transcriptional regulatory signaling in hepatic stellate cells

ABSTRACT: Liver injury causes “transdifferentiation” of quiescent hepatic stellate cells (Q-HSCs) into wound repairing myofibroblasts (MF-HSCs), whose uncontrolled activation leads ultimately to liver fibrosis. Although this process is triggered by deep metabolic and transcriptional reprogramming, functional links between these two key events are not yet understood. Here, using a compendium of in vitro, ex vivo and in vivo models of fibrogenic liver injuries in addition to human liver samples, we report that O-linked β D N acetylglucosaminylation (O GlcNAcylation), a post-translational modification (PTM) considered as nutritional sensor, is increased during myofibroblastic activation of HSCs and is required for their pro-fibrotic activities. Mechanistically, a multi omics approach combining proteomic, epigenomic and transcriptomic data mining revealed that O GlcNAcylation controls the transcriptional program of MF-HSCs by targeting the key fibrogenic transcription factors Basonuclin 2 (BNC2) and TEA domain transcription factor 4 (TEAD4) together with the Yes associated protein 1 (YAP1) co-activator. Indeed, inhibition of protein O GlcNAcylation impedes their stability leading to decreased functionality of the BNC2/TEAD4/YAP1 complex towards promoting activation of fibrogenic transcriptional regulatory elements. Altogether, this study unravels the fibrogenic role of protein O-GlcNAcylation identifying a vulnerable regulatory process in activated HSCs.

INSTRUMENT(S): Q Exactive Plus

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Hepatic Stellate Cell, Liver

DISEASE(S): Liver Disease

SUBMITTER: BRAY FABRICE

LAB HEAD: Fabrice BRay

PROVIDER: PXD045860 | Pride | 2024-05-21

REPOSITORIES: Pride

ACCESS DATA

Dataset's files

Source:

Items per page:

1 - 5 of 25

Similar Datasets

Project description:The O-N-acetyl-β-D-glucosaminylation, termed O-GlcNAcylation, is an atypical glycosylation corresponding to the transfer of a unique saccharide, the N-acetyl-β-D-glucosamine, on the hydroxyl group of serine and threonine amino acids of nuclear, cytosolic and mitochondrial proteins. Because of its dynamism, its reversibility and the swiftness of GlcNAc moieties transfer, O-GlcNAcylation is akin to phosphorylation and it is able to respond rapidly to both extracellular and intracellular demands. This post-translational modification is highly represented on intracellular proteins (in particular cytosolic, nuclear and mitochondrial proteins), and is involved in almost if not all cellular processes. O-GlcNAcylation is nowadays clearly associated with the etiology of several acquired diseases, in particular diabetes, neuro-degenerative disorders, cardiovascular diseases or cancer. The O-GlcNAcylation rapidly emerged as a major cellular mechanism which compete with phosphorylation in terms of modified proteins and the importance in cellular physiology. The O-GlcNAcylated sites could also correspond to phosphorylated ones; many proteins are modified by both O-GlcNAc and phosphates groups, and these two post-translational modifications could compete to the same or at neighboring sites. However, despite the undeniable role of O-GlcNAcylation in the modulation of almost all cellular processes, its precise function remains still misunderstood, mainly because of the unknown position of O-GlcNAcylation on specific domains of proteins. Thus, the precise localization of O-GlcNAcylated sites remains an indispensable prerequisite for the fine understanding of its biological function. However, mapping the O-GlcNAcylated sites remains laborious, but challenging, because of (i) the low stoichiometry of O-GlcNAcylation; (ii) the ion suppression of the modified peptide by the unmodified peptide present in larger excess; and (iii) the labile β bound between serine or threonine and the O-GlcNAc moiety which is broken during the CID (Collision-Induced Dissociation) fragmentation process, leading to loss of site information. To respond to this biological demand and to overcome these difficulties, enrichment of O-GlcNAc modified proteins and the use of other fragmentation processes like ECD (Electron Capture Dissociation), ETD (Electron Transfer Dissociation), or HCD (High-energy Collisional Dissociation), able to limit the O-GlcNAc loss during the fragmentation, are crucial. Our strategy was an alternative, specific, efficient and selective purification of O-GlcNAc bearing proteins from skeletal muscle cells by the use of the Click chemistry methodology. To extensively map O-GlcNAc sites on proteins, we proposed herein an intensive fractionation of the muscle cell proteome according to solubility, hydrophobicity and isoelectric point of proteins. The method of Click chemistry was achieved on each enriched-fraction containing proteins of interest.

Project description:Over the past decades, protein O-GlcNAcylation has been found to play a fundamental role in cell cycle control, metabolism, transcriptional regulation, and cellular signaling. Nevertheless, quantitative approaches to determine in vivo GlcNAc dynamics at a large-scale are still not readily available. Here, we have developed an approach to isotopically label O-GlcNAc modifications on proteins by producing 13C-labeled UDP-GlcNAc from 13C6-glucose via the hexosamine biosynthetic pathway. This metabolic labeling was combined with quantitative mass spectrometry-based proteomics to determine site-specific protein O-GlcNAcylation turnover rates. First, an efficient enrichment method for O-GlcNAc peptides was developed with the use of phenylboronic acid solid-phase extraction and anhydrous DMSO. The near stoichiometry reaction between the diol of GlcNAc and boronic acid dramatically improved the enrichment efficiency. Additionally, our kinetic model for turnover rates integrates both metabolomic and proteomic data, which increase the accuracy of the turnover rate estimation. Other advantages of this metabolic labeling method include in vivo application, direct labeling of the O-GlcNAc sites and higher confidence for site identification. Concentrating only on nuclear localized GlcNAc modified proteins, we are able to identify 159 O-GlcNAc sites on 74 proteins and determine turnover rates of 24 O-GlcNAc peptides from 21 proteins extracted from HeLa nuclei. In general, we found O-GlcNAcylation turnover rates are slower than those published for phosphorylation or acetylation. Nevertheless, the rates widely varied depending on both the protein and the residue modified. We believe this methodology can be broadly applied to reveal turnovers/dynamics of protein O-GlcNAcylation from different biological states and will provide more information on the significance of site-specific O-GlcNAcylation, enabling us to study the temporal dynamics of this critical modification in a site-specific manner for the first time.

			Action	DRS
	Bille-ninon.msf	Msf
	Bille-ninon.raw	Raw
	CTRL-Noy.msf	Msf
	CTRL-Noy.raw	Raw
	CTRL-cyto.msf	Msf

Dataset Information

O-GlcNAcylation controls pro-fibrotic transcriptional regulatory signaling in hepatic stellate cells

Dataset's files

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets