Seroatlas · Human Serome Atlas

LMBRD1

Lysosomal cobalamin transport escort protein LMBD1

Also known as: bA810I22.1, C6orf209, cblF, FLJ11240, LMBD1_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q9NUN5
Gene
LMBRD1
Ensembl
ENSG00000168216
Chromosome
6
Canonical length
540 aa
Protein class
Disease related genes, Human disease related genes, Potential drug targets, Predicted membrane proteins, Transporters
Subcellular location
Vesicles

OverviewNCBI Gene

This gene encodes a lysosomal membrane protein that may be involved in the transport and metabolism of cobalamin. This protein also interacts with the large form of the hepatitis delta antigen and may be required for the nucleocytoplasmic shuttling of the hepatitis delta virus. Mutations in this gene are associated with the vitamin B12 metabolism disorder termed, homocystinuria-megaloblastic anemia complementation type F.[provided by RefSeq, Oct 2009]

Canonical amino-acid sequenceUniProt

540 residues, UniProt reviewed canonical sequence.

>Q9NUN5|LMBRD1
     1  MATSGAASAE LVIGWCIFGL LLLAILAFCW IYVRKYQSRR ESEVVSTITA IFSLAIALIT
    61  SALLPVDIFL VSYMKNQNGT FKDWANANVS RQIEDTVLYG YYTLYSVILF CVFFWIPFVY
   121  FYYEEKDDDD TSKCTQIKTA LKYTLGFVVI CALLLLVGAF VPLNVPNNKN STEWEKVKSL
   181  FEELGSSHGL AALSFSISSL TLIGMLAAIT YTAYGMSALP LNLIKGTRSA AYERLENTED
   241  IEEVEQHIQT IKSKSKDGRP LPARDKRALK QFEERLRTLK KRERHLEFIE NSWWTKFCGA
   301  LRPLKIVWGI FFILVALLFV ISLFLSNLDK ALHSAGIDSG FIIFGANLSN PLNMLLPLLQ
   361  TVFPLDYILI TIIIMYFIFT SMAGIRNIGI WFFWIRLYKI RRGRTRPQAL LFLCMILLLI
   421  VLHTSYMIYS LAPQYVMYGS QNYLIETNIT SDNHKGNSTL SVPKRCDADA PEDQCTVTRT
   481  YLFLHKFWFF SAAYYFGNWA FLGVFLIGLI VSCCKGKKSV IEGVDEDSDI SDDEPSVYSA

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against LMBRD1 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
Cell surface
Secreted
No
Transmembrane segments
9
Mean surface accessibility (rSASA)
0.28
Highest tissue expression
50 nTPM

Expression across tissuesHPA

Tissue

  • kidney: 50 nTPM
  • adrenal gland: 38 nTPM
  • liver: 33 nTPM
  • spinal cord: 33 nTPM
  • parathyroid gland: 30 nTPM
  • adipose tissue: 29 nTPM

Single-cell type

  • b-cells: 327 nCPM
  • neutrophils: 324 nCPM
  • esophageal apical cells: 258 nCPM
  • enterocytes: 248 nCPM
  • bergmann glia: 224 nCPM
  • pituicytes/fscs: 224 nCPM

Immune cell

  • naive B-cell: 21 nTPM
  • memory B-cell: 12 nTPM
  • neutrophil: 11 nTPM
  • basophil: 6.7 nTPM
  • non-classical monocyte: 4.8 nTPM
  • eosinophil: 4 nTPM

Brain region

  • cerebellum: 38 nTPM
  • white matter: 28 nTPM
  • medulla oblongata: 24 nTPM
  • choroid plexus: 23 nTPM
  • cerebral cortex: 20 nTPM
  • midbrain: 20 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about LMBRD1.

Disease | AllUniProt

Conditions LMBRD1 is implicated in, by any mechanism.

  • Methylmalonic aciduria and homocystinuria, cblF type (MAHCF) MIM:277380

Disease | GeneticClinVar

58 pathogenic / likely-pathogenic of 552 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)
0.93
gnomAD pLI
0
gnomAD missense Z
0.26
DepMap mean gene effect
0.05
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% 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

InteractionsUniProt · HPA

Protein binding partners of LMBRD1 in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads LMBRD1 as an antibody target. Whether an autoantibody or antibody against LMBRD1 could matter depends on whether native LMBRD1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

LMBRD1 is annotated at the cell surface, where native LMBRD1 is exposed to circulating antibodies and is a prime autoantibody target that could block, deplete, or overstimulate it.

Annotation status

The present source text does not explicitly label LMBRD1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/LMBRD1. 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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