GO_REF:0000002

Gene Ontology annotation through association of InterPro records with GO terms

GO_REF:0000033

Annotation inferences using phylogenetic trees

GO_REF:0000044

Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location vocabulary mapping

GO_REF:0000117

Electronic Gene Ontology annotations created by ARBA machine learning models

GO_REF:0000120

Combined Automated Annotation using Multiple IEA Methods

PMID:10409699

Identification, expression, and characterization of a cDNA encoding human endoplasmic reticulum mannosidase I, the enzyme that catalyzes the first mannose trimming step in mammalian Asn-linked oligosaccharide biosynthesis.

Human ER mannosidase I is the enzyme catalyzing the first mannose-trimming step of Asn-linked oligosaccharide biosynthesis; the reaction requires divalent cations (Ca2+).

PMID:10521544

Cloning and expression of a specific human alpha 1,2-mannosidase that trims Man9GlcNAc2 to Man8GlcNAc2 isomer B during N-glycan biosynthesis.

The recombinant human enzyme removes a single alpha-1,2-mannose from Man9GlcNAc to produce Man8GlcNAc isomer B; calcium is required and dMNJ and kifunensine inhibit activity.

PMID:12090241

The specificity of the yeast and human class I ER alpha 1,2-mannosidases involved in ER quality control is not as strict previously reported.

The human class I ER alpha-1,2-mannosidase can trim more than a single mannose, revising the strict single-residue specificity model.

PMID:15713668

Mechanism of class 1 (glycosylhydrolase family 47) alpha-mannosidases involved in N-glycan processing and endoplasmic reticulum quality control.

Structural and mutagenesis study of the GH47 inverting hydrolytic mechanism, mapping catalytic residues of human ERManI.

PMID:18003979

Endoplasmic reticulum (ER) mannosidase I is compartmentalized and required for N-glycan trimming to Man5-6GlcNAc2 in glycoprotein ER-associated degradation.

ERManI is concentrated in the pericentriolar ER quality control compartment and is required for trimming to Man5-6GlcNAc2 and for ERAD in cells.

PMID:19946888

Defining the membrane proteome of NK cells.

PMID:21062743

Mannose trimming is required for delivery of a glycoprotein from EDEM1 to XTP3-B and to late endoplasmic reticulum-associated degradation steps.

ERManI-dependent mannose trimming is required to hand off substrate from EDEM1 to the late ERAD lectin XTP3-B and downstream HRD1/SCF(Fbs2) ligases.

PMID:22160784

In vitro mannose trimming property of human ER alpha-1,2 mannosidase I.

Recombinant hERManI generates Man6GlcNAc2 and Man5GlcNAc2 in vitro and preferentially removes mannoses from misfolded glycoproteins, indicating conformational selectivity.

PMID:24769233

Proteomic analysis of cerebrospinal fluid extracellular vesicles: a comprehensive dataset.

PMID:32958677

The cytoplasmic tail of human mannosidase Man1b1 contributes to catalysis-independent quality control of misfolded alpha1-antitrypsin.

Beyond its luminal catalytic alpha-1,2-mannosidase activity, MAN1B1/ERManI contributes to ERAD of misfolded glycoproteins (NHK and Z variants of alpha1-antitrypsin) through an unconventional, catalysis-independent pathway controlled by its evolutionarily extended N-terminal cytoplasmic tail; this tail-dependent degradation does not require the substrate's N-glycans and drives proteasomal degradation.

PMID:25411339

Mammalian ER mannosidase I resides in quality control vesicles, where it encounters its glycoprotein substrates.

ERManI resides at steady state in mobile ER-like quality control vesicles (QCVs) that deliver ERAD substrates and converge on the ERQC; the apparent Golgi pattern is a fixation artifact.

Reactome:R-HSA-4793949

Defective MAN1B1 does not hydrolyse 1,2-linked mannose (a branch)

Reactome:R-HSA-901024

MAN1B1 hydrolyses 1,2-linked mannose (a branch)

Reactome:R-HSA-901032

ER Quality Control Compartment (ERQC)

Reactome:R-HSA-901036

MAN1B1 hydrolyses a second 1,2-linked mannose (a branch)

Reactome:R-HSA-901039

MAN1B1 hydrolyses 1,2-linked mannose (c branch)

Reactome:R-HSA-901074

MAN1B1,EDEM2 hydrolyse 1,2-linked mannose (b branch)

Reactome:R-HSA-9036008

Defective MAN1B1 does not hydrolyse a second 1,2-linked mannose (a branch)

Reactome:R-HSA-9036011

Defective MAN1B1 does not hydrolyse 1,2-linked mannose (b branch)

Reactome:R-HSA-9036012

Defective MAN1B1 does not hydrolyse 1,2-linked mannose (c branch)

Reactome:R-HSA-9694548

Maturation of spike protein

Reactome:R-HSA-9696807

N-glycan mannose trimming of Spike

file:human/MAN1B1/MAN1B1-uniprot.txt

UniProt entry Q9UKM7 (MA1B1_HUMAN), Endoplasmic reticulum mannosyl-oligosaccharide 1,2-alpha-mannosidase

Calcium-dependent GH47 alpha-1,2-mannosidase (EC 3.2.1.113) of the ER membrane (type II single-pass) that trims Man9GlcNAc2 to Man8GlcNAc2 isomer B and, at high concentration, to Man5-6GlcNAc2, targeting misfolded glycoproteins for ERAD; biallelic variants cause Rafiq syndrome/MAN1B1-CDG.