Seroatlas · Human Serome Atlas

MAN1B1

Endoplasmic reticulum mannosyl-oligosaccharide 1,2-alpha-mannosidase

Also known as: ERMan1, ERManI, MA1B1_HUMAN, MANA-ER, MRT15

Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene

Protein identityUniProt · HPA

UniProt accession
Q9UKM7
Gene
MAN1B1
Ensembl
ENSG00000177239
Chromosome
9
Canonical length
699 aa
Protein class
Disease related genes, Enzymes, Human disease related genes, Metabolic proteins, Plasma proteins, Potential drug targets, Predicted membrane proteins
Subcellular location
Vesicles

OverviewNCBI Gene

This gene encodes an enzyme belonging to the glycosyl hydrolase 47 family. This enzyme functions in N-glycan biosynthesis, and is a class I alpha-1,2-mannosidase that specifically converts Man9GlcNAc to Man8GlcNAc isomer B. It is required for N-glycan trimming to Man5-6GlcNAc2 in the endoplasmic-reticulum-associated degradation pathway. Mutations in this gene cause autosomal-recessive intellectual disability. Alternative splicing results in multiple transcript variants. A related pseudogene has been identified on chromosome 11. [provided by RefSeq, Dec 2011]

Canonical amino-acid sequenceUniProt

699 residues, UniProt reviewed canonical sequence.

>Q9UKM7|MAN1B1
     1  MAACEGRRSG ALGSSQSDFL TPPVGGAPWA VATTVVMYPP PPPPPHRDFI SVTLSFGENY
    61  DNSKSWRRRS CWRKWKQLSR LQRNMILFLL AFLLFCGLLF YINLADHWKA LAFRLEEEQK
   121  MRPEIAGLKP ANPPVLPAPQ KADTDPENLP EISSQKTQRH IQRGPPHLQI RPPSQDLKDG
   181  TQEEATKRQE APVDPRPEGD PQRTVISWRG AVIEPEQGTE LPSRRAEVPT KPPLPPARTQ
   241  GTPVHLNYRQ KGVIDVFLHA WKGYRKFAWG HDELKPVSRS FSEWFGLGLT LIDALDTMWI
   301  LGLRKEFEEA RKWVSKKLHF EKDVDVNLFE STIRILGGLL SAYHLSGDSL FLRKAEDFGN
   361  RLMPAFRTPS KIPYSDVNIG TGVAHPPRWT SDSTVAEVTS IQLEFRELSR LTGDKKFQEA
   421  VEKVTQHIHG LSGKKDGLVP MFINTHSGLF THLGVFTLGA RADSYYEYLL KQWIQGGKQE
   481  TQLLEDYVEA IEGVRTHLLR HSEPSKLTFV GELAHGRFSA KMDHLVCFLP GTLALGVYHG
   541  LPASHMELAQ ELMETCYQMN RQMETGLSPE IVHFNLYPQP GRRDVEVKPA DRHNLLRPET
   601  VESLFYLYRV TGDRKYQDWG WEILQSFSRF TRVPSGGYSS INNVQDPQKP EPRDKMESFF
   661  LGETLKYLFL LFSDDPNLLS LDAYVFNTEA HPLPIWTPA

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against MAN1B1 can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability
Other membrane
Secreted
No
Transmembrane segments
1
Mean surface accessibility (rSASA)
0.35
Highest tissue expression
28 nTPM

Expression across tissuesHPA

Tissue

  • ovary: 28 nTPM
  • salivary gland: 20 nTPM
  • pancreas: 20 nTPM
  • placenta: 19 nTPM
  • fallopian tube: 19 nTPM
  • blood vessel: 19 nTPM

Single-cell type

  • extravillous trophoblasts: 102 nCPM
  • migrating cytotrophoblasts: 66 nCPM
  • cytotrophoblasts: 62 nCPM
  • syncytiotrophoblasts: 50 nCPM
  • decidual stromal cells: 48 nCPM
  • differentiating spermatogonia: 47 nCPM

Immune cell

  • non-classical monocyte: 37 nTPM
  • myeloid DC: 33 nTPM
  • intermediate monocyte: 30 nTPM
  • total PBMC: 29 nTPM
  • gdT-cell: 29 nTPM
  • T-reg: 29 nTPM

Brain region

  • pons: 17 nTPM
  • choroid plexus: 15 nTPM
  • hypothalamus: 14 nTPM
  • white matter: 14 nTPM
  • medulla oblongata: 13 nTPM
  • midbrain: 12 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about MAN1B1.

Disease | AllUniProt

Conditions MAN1B1 is implicated in, by any mechanism.

Disease | GeneticClinVar

52 pathogenic / likely-pathogenic of 646 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance)
0.83
gnomAD pLI
0
gnomAD missense Z
-0.73
DepMap mean gene effect
-0.03
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 5% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads MAN1B1 as an antibody target. Whether an autoantibody or antibody against MAN1B1 could matter depends on whether native MAN1B1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

MAN1B1 is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

The present source text does not explicitly label MAN1B1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/MAN1B1. Study-independent annotations aggregated from UniProt, Human Protein Atlas, PubMed, IEDB, Pfam, InterPro, Gene Ontology, AlphaFold, gnomAD, DepMap, ClinVar, TCGA. Catalog release seroatlas-reviewed-human-uniprot-20260313.

Seroatlas is the reference for exploring autoantibody and antibody serology at the human-protein level: the autoreactome and human serome, multiplex serology (HuProt, HuScan, VirScan, PhIP-Seq).

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