Endoplasmic reticulum mannosyl-oligosaccharide 1,2-alpha-mannosidase (MAN1B1)

Involved in glycoprotein quality control targeting of misfolded glycoproteins for degradation. It primarily trims one alpha-1,2-linked mannose residue from Man(9)GlcNAc(2) to produce Man(8)GlcNAc(2), but at high enzyme concentrations, as found in the ER quality control compartment (ERQC), it cuts the carbohydrates to Man(5-6)GlcNAc(2).

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