Dataset Information

Genotype-dependent N-glycosylation and newly discovered O-glycosylation affecting HRG plasmin cleavage

ABSTRACT: Histidine-rich glycoprotein (HRG) is an abundant plasma glycoprotein with three reported N-glycosylation sites, which integrates many biological processes such as antiangiogenic activity, immune complex clearance and pathogen clearance. Importantly, the protein is known to have five genetic variants with minor allele frequencies of more than 10%, meaning these exist with substantial frequency in the human population. Among them, Pro204Ser can induce a new N-glycosylation site at Asn202. Considerable research has been performed into the biological activity of HRG, while research on its glycosylation is rare. To close this knowledge gap, we used C18-based LC-MS/MS to investigate the glycosylation characteristics of HRG from human plasma, recombinant Chinese hamster ovary (CHO) cell lines and recombinant human embryonic kidney (HEK293) cell lines with targeted mutations. Within human plasma endogenous HRG, every N-glycosylation site proved dominant with a sialylated diantennary complex-type glycan. For the recombinant HRGs, on the other hand, glycans showed different antennarities, sialylation and core-fucosylation, as well as the appearance of oligomannose glycans, LacdiNAc and antennary fucosylation. Furthermore, we discovered a previously unreported O-glycosylation site on residues Thr273/Thr274, which showed an approximate 90% glycan occupancy in all HRG types. To investigate the relevance of HRG glycosylation characteristics and its biological function, we set up an assay to study the plasmin cleavage of HRG under various conditions. In doing so, we showed that the sialylation of the new O-glycan, as well as the genotype-dependent N-glycosylation, significantly influenced the plasmin cleavage of HRG.

INSTRUMENT(S): Orbitrap Fusion Lumos, Orbitrap Fusion

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Blood Plasma, Cell Culture

SUBMITTER: Yang Zou

LAB HEAD: Karli Reiding

PROVIDER: PXD044353 | Pride | 2024-05-21

REPOSITORIES: Pride

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Genotype-dependent N-glycosylation and newly exposed O-glycosylation affect plasmin-induced cleavage of histidine-rich glycoprotein (HRG).

Zou Yang Y Pronker Matti F MF Damen J Mirjam A JMA Heck Albert J R AJR Reiding Karli R KR

The Journal of biological chemistry 20240124 3

Histidine-rich glycoprotein (HRG) is an abundant plasma protein harboring at least three N-glycosylation sites. HRG integrates many biological processes, such as coagulation, antiangiogenic activity, and pathogen clearance. Importantly, HRG is known to exhibit five genetic variants with minor allele frequencies of more than 10%. Among them, Pro204Ser can induce a fourth N-glycosylation site (Asn202). Considerable efforts have been made to reveal the biological function of HRG, whereas data on HR ...[more]

PMID: 38272220

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	CHO_100_EthcD.raw.rar	Raw
	CHO_100_HCD.raw	Raw
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	CHO_100_sHCD.raw	Raw