Seroatlas · Human Serome Atlas

MTNR1B

Melatonin receptor type 1B

Also known as: MTR1B_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P49286
Gene
MTNR1B
Ensembl
ENSG00000134640
Chromosome
11
Canonical length
362 aa
Protein class
FDA approved drug targets, G-protein coupled receptors, Human disease related genes, Predicted intracellular proteins, Predicted membrane proteins

OverviewNCBI Gene

This gene encodes one of two high affinity forms of a receptor for melatonin, the primary hormone secreted by the pineal gland. This gene product is an integral membrane protein that is a G-protein coupled, 7-transmembrane receptor. It is found primarily in the retina and brain although this detection requires RT-PCR. It is thought to participate in light-dependent functions in the retina and may be involved in the neurobiological effects of melatonin. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

362 residues, UniProt reviewed canonical sequence.

>P49286|MTNR1B
     1  MSENGSFANC CEAGGWAVRP GWSGAGSARP SRTPRPPWVA PALSAVLIVT TAVDVVGNLL
    61  VILSVLRNRK LRNAGNLFLV SLALADLVVA FYPYPLILVA IFYDGWALGE EHCKASAFVM
   121  GLSVIGSVFN ITAIAINRYC YICHSMAYHR IYRRWHTPLH ICLIWLLTVV ALLPNFFVGS
   181  LEYDPRIYSC TFIQTASTQY TAAVVVIHFL LPIAVVSFCY LRIWVLVLQA RRKAKPESRL
   241  CLKPSDLRSF LTMFVVFVIF AICWAPLNCI GLAVAINPQE MAPQIPEGLF VTSYLLAYFN
   301  SCLNAIVYGL LNQNFRREYK RILLALWNPR HCIQDASKGS HAEGLQSPAP PIIGVQHQAD
   361  AL

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against MTNR1B 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
7
Mean surface accessibility (rSASA)
0.34
Highest tissue expression
0.9 nTPM

Expression across tissuesHPA

Tissue

  • placenta: 0.9 nTPM
  • testis: 0.4 nTPM
  • basal ganglia: 0.3 nTPM
  • tonsil: 0.3 nTPM
  • cerebral cortex: 0.1 nTPM
  • adipose tissue: 0 nTPM

Single-cell type

  • syncytiotrophoblasts: 6.8 nCPM
  • ependymal cells: 2.3 nCPM
  • brain inhibitory neurons: 1.6 nCPM
  • granulosa cells: 0.8 nCPM
  • early spermatids: 0.7 nCPM
  • late spermatids: 0.7 nCPM

Immune cell

  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM
  • MAIT T-cell: 0 nTPM

Brain region

  • medulla oblongata: 7.2 nTPM
  • basal ganglia: 6.4 nTPM
  • midbrain: 6.3 nTPM
  • hippocampal formation: 5.5 nTPM
  • amygdala: 5.4 nTPM
  • spinal cord: 5.2 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about MTNR1B.

Disease | ImmuneIEDB

Conditions an epitope on MTNR1B was assayed in.

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)
1.29
gnomAD pLI
0
gnomAD missense Z
-0.45
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 MTNR1B 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 MTNR1B as an antibody target. Whether an autoantibody or antibody against MTNR1B could matter depends on whether native MTNR1B is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

MTNR1B is annotated at the cell surface, where native MTNR1B 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 MTNR1B as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/MTNR1B. 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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