Seroatlas · Human Serome Atlas

MTRR

Methionine synthase reductase

Also known as: cblE, MTRR_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q9UBK8
Gene
MTRR
Ensembl
ENSG00000124275
Chromosome
5
Canonical length
698 aa
Protein class
Disease related genes, Enzymes, Human disease related genes, Metabolic proteins, Potential drug targets, Predicted intracellular proteins
Subcellular location
Nucleoplasm,Intermediate filaments,Cytosol

OverviewNCBI Gene

This gene encodes a member of the ferredoxin-NADP(+) reductase (FNR) family of electron transferases. This protein functions in the synthesis of methionine by regenerating methionine synthase to a functional state. Because methionine synthesis requires methyl-group transfer by a folate donor, activity of the encoded enzyme is important for folate metabolism and cellular methylation. Mutations in this gene can cause homocystinuria-megaloblastic anemia, cbl E type. Alternative splicing of this gene results in multiple transcript variants. [provided by RefSeq, Dec 2015]

Canonical amino-acid sequenceUniProt

698 residues, UniProt reviewed canonical sequence.

>Q9UBK8|MTRR
     1  MRRFLLLYAT QQGQAKAIAE EICEQAVVHG FSADLHCISE SDKYDLKTET APLVVVVSTT
    61  GTGDPPDTAR KFVKEIQNQT LPVDFFAHLR YGLLGLGDSE YTYFCNGGKI IDKRLQELGA
   121  RHFYDTGHAD DCVGLELVVE PWIAGLWPAL RKHFRSSRGQ EEISGALPVA SPASSRTDLV
   181  KSELLHIESQ VELLRFDDSG RKDSEVLKQN AVNSNQSNVV IEDFESSLTR SVPPLSQASL
   241  NIPGLPPEYL QVHLQESLGQ EESQVSVTSA DPVFQVPISK AVQLTTNDAI KTTLLVELDI
   301  SNTDFSYQPG DAFSVICPNS DSEVQSLLQR LQLEDKREHC VLLKIKADTK KKGATLPQHI
   361  PAGCSLQFIF TWCLEIRAIP KKAFLRALVD YTSDSAEKRR LQELCSKQGA ADYSRFVRDA
   421  CACLLDLLLA FPSCQPPLSL LLEHLPKLQP RPYSCASSSL FHPGKLHFVF NIVEFLSTAT
   481  TEVLRKGVCT GWLALLVASV LQPNIHASHE DSGKALAPKI SISPRTTNSF HLPDDPSIPI
   541  IMVGPGTGIA PFIGFLQHRE KLQEQHPDGN FGAMWLFFGC RHKDRDYLFR KELRHFLKHG
   601  ILTHLKVSFS RDAPVGEEEA PAKYVQDNIQ LHGQQVARIL LQENGHIYVC GDAKNMAKDV
   661  HDALVQIISK EVGVEKLEAM KTLATLKEEK RYLQDIWS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against MTRR 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
Intracellular
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.29
Highest tissue expression
31 nTPM

Expression across tissuesHPA

Tissue

  • tongue: 31 nTPM
  • skeletal muscle: 27 nTPM
  • liver: 18 nTPM
  • retina: 18 nTPM
  • kidney: 17 nTPM
  • heart muscle: 14 nTPM

Single-cell type

  • late spermatids: 219 nCPM
  • alveolar cells type 2: 106 nCPM
  • adrenal medulla cells: 96 nCPM
  • early spermatids: 77 nCPM
  • respiratory ciliated cells: 75 nCPM
  • cardiomyocytes: 73 nCPM

Immune cell

  • T-reg: 9.1 nTPM
  • MAIT T-cell: 7 nTPM
  • memory CD4 T-cell: 6.5 nTPM
  • memory CD8 T-cell: 5.7 nTPM
  • intermediate monocyte: 5.5 nTPM
  • basophil: 5.4 nTPM

Brain region

  • white matter: 48 nTPM
  • medulla oblongata: 31 nTPM
  • basal ganglia: 31 nTPM
  • pons: 30 nTPM
  • midbrain: 30 nTPM
  • cerebellum: 29 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about MTRR.

Disease | AllUniProt

Conditions MTRR is implicated in, by any mechanism.

  • Homocystinuria-megaloblastic anemia, cblE type (HMAE) MIM:236270
  • Neural tube defects, folate-sensitive (NTDFS) MIM:601634

Disease | GeneticClinVar

159 pathogenic / likely-pathogenic of 1,082 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

Disease | ImmuneIEDB

Conditions an epitope on MTRR 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)
0.98
gnomAD pLI
0
gnomAD missense Z
-0.67
DepMap mean gene effect
-0.13
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 10% 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 MTRR as an antibody target. Whether an autoantibody or antibody against MTRR could matter depends on whether native MTRR is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

MTRR 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 MTRR as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

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