Taxonomic group: fungi / Ascomycota
(Phylum: Ascomycota)
NCBI PubMed ID: 31311856Publication DOI: 10.1074/jbc.RA119.009491Journal NLM ID: 2985121RPublisher: Baltimore, MD: American Society for Biochemistry and Molecular Biology
Correspondence: Suzuki T <tsuzuki_gm
riken.jp>
Institutions: Glycometabolic Biochemistry Laboratory, RIKEN-Cluster for Pioneering Research, Wako, Japan, Department of Academic Research Support Promotion Facility, Center for Research Promotion and Support, Fujita Health University, Toyoake, Japan, Collaborative Research Institute for Innovative Microbiology, Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan, RNA Systems Biochemistry Laboratory, RIKEN Cluster for Pioneering Research, Wako, Japan, Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan
In eukaryotic cells, unconjugated oligosaccharides that are structurally related to N-glycans (i.e. free N-glycans) are generated either from misfolded N-glycoproteins destined for the endoplasmic reticulum-associated degradation or from lipid-linked oligosaccharides, donor substrates for N-glycosylation of proteins. The mechanism responsible for the generation of free N-glycans is now well-understood, but the issue of whether other types of free glycans are present remains unclear. Here, we report on the accumulation of free, O-mannosylated glycans in budding yeast that were cultured in medium containing mannose as the carbon source. A structural analysis of these glycans revealed that their structures are identical to those of O-mannosyl glycans that are attached to glycoproteins. Deletion of the cyc8 gene, which encodes for a general transcription repressor, resulted in the accumulation of excessive amounts of free O-glycans, concomitant with a severe growth defect, a reduction in the level of an O-mannosylated protein, and compromised cell wall integrity. Our findings provide evidence in support of a regulated pathway for the degradation of O-glycoproteins in yeast and offer critical insights into the catabolic mechanisms that control the fate of O-glycosylated proteins.
cell wall, glycosylation, glycoprotein, O-glycosylation, glycobiology, yeast, catabolite regulation, free glycan, glucose metabolism, yeast metabolism
Structure type: oligomer ; 605.3 [M+C5H6N2Na-H2O]+
Location inside paper: Table III, b
Compound class: oligosaccharide
Contained glycoepitopes: IEDB_130701,IEDB_136104,IEDB_137485,IEDB_140116,IEDB_141830,IEDB_143632,IEDB_144983,IEDB_152206,IEDB_983930,SB_136,SB_196,SB_44,SB_67,SB_72
Methods: PCR, SDS-PAGE, MALDI-TOF MS, HPLC, immunoblotting, enzymatic digestion, RP-HPLC, cell growth, RNA sequencing, gene expression, derivatization, centrifugation, ion exchange chromatography
Enzymes that release or process the structure: α-mannosidase, α-1,2-mannosidase, α-1,2/3-mannosidase
Related record ID(s): 49831, 49833, 49834
NCBI Taxonomy refs (TaxIDs): 1247190Reference(s) to other database(s): GTC:G09342SH
Show glycosyltransferases
There is only one chemically distinct structure:
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