Seroatlas · Human Serome Atlas

LETM1

Mitochondrial proton/calcium exchanger protein

Also known as: LETM1_HUMAN, Mdm38, SLC55A1.

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

Protein identityUniProt · HPA

UniProt accession
O95202
Gene
LETM1
Ensembl
ENSG00000168924
Chromosome
4
Canonical length
739 aa
Protein class
Human disease related genes, Predicted membrane proteins, Transporters
Subcellular location
Mitochondria
Quaternary structure
Homohexamer

OverviewNCBI Gene

This gene encodes a protein that is localized to the inner mitochondrial membrane. The protein functions to maintain the mitochondrial tubular shapes and is required for normal mitochondrial morphology and cellular viability. Mutations in this gene cause Wolf-Hirschhorn syndrome, a complex malformation syndrome caused by the deletion of parts of the distal short arm of chromosome 4. Related pseudogenes have been identified on chromosomes 8, 15 and 19. [provided by RefSeq, Oct 2009]

Canonical amino-acid sequenceUniProt

739 residues, UniProt reviewed canonical sequence.

>O95202|LETM1
     1  MASILLRSCR GRAPARLPPP PRYTVPRGSP GDPAHLSCAS TLGLRNCLNV PFGCCTPIHP
    61  VYTSSRGDHL GCWALRPECL RIVSRAPWTS TSVGFVAVGP QCLPVRGWHS SRPVRDDSVV
   121  EKSLKSLKDK NKKLEEGGPV YSPPAEVVVK KSLGQRVLDE LKHYYHGFRL LWIDTKIAAR
   181  MLWRILNGHS LTRRERRQFL RICADLFRLV PFLVFVVVPF MEFLLPVAVK LFPNMLPSTF
   241  ETQSLKEERL KKELRVKLEL AKFLQDTIEE MALKNKAAKG SATKDFSVFF QKIRETGERP
   301  SNEEIMRFSK LFEDELTLDN LTRPQLVALC KLLELQSIGT NNFLRFQLTM RLRSIKADDK
   361  LIAEEGVDSL NVKELQAACR ARGMRALGVT EDRLRGQLKQ WLDLHLHQEI PTSLLILSRA
   421  MYLPDTLSPA DQLKSTLQTL PEIVAKEAQV KVAEVEGEQV DNKAKLEATL QEEAAIQQEH
   481  REKELQKRSE VAKDFEPERV VAAPQRPGTE PQPEMPDTVL QSETLKDTAP VLEGLKEEEI
   541  TKEEIDILSD ACSKLQEQKK SLTKEKEELE LLKEDVQDYS EDLQEIKKEL SKTGEEKYVE
   601  ESKASKRLTK RVQQMIGQID GLISQLEMDQ QAGKLAPANG MPTGENVISV AELINAMKQV
   661  KHIPESKLTS LAAALDENKD GKVNIDDLVK VIELVDKEDV HISTSQVAEI VATLEKEEKV
   721  EEKEKAKEKA EKEVAEVKS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against LETM1 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)
0.45
Highest tissue expression
24 nTPM

Expression across tissuesHPA

Tissue

  • thymus: 24 nTPM
  • esophagus: 23 nTPM
  • colon: 19 nTPM
  • heart muscle: 19 nTPM
  • skeletal muscle: 18 nTPM
  • cerebellum: 16 nTPM

Single-cell type

  • colonocytes: 104 nCPM
  • esophageal suprabasal cells: 90 nCPM
  • early primary spermatocytes: 83 nCPM
  • esophageal apical cells: 72 nCPM
  • esophageal basal cells: 71 nCPM
  • suprabasal keratinocytes: 65 nCPM

Immune cell

  • plasmacytoid DC: 13 nTPM
  • NK-cell: 5.8 nTPM
  • gdT-cell: 5.7 nTPM
  • MAIT T-cell: 5.6 nTPM
  • non-classical monocyte: 5 nTPM
  • intermediate monocyte: 4.9 nTPM

Brain region

  • thalamus: 35 nTPM
  • hypothalamus: 34 nTPM
  • cerebral cortex: 33 nTPM
  • amygdala: 33 nTPM
  • midbrain: 32 nTPM
  • basal ganglia: 31 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about LETM1.

Disease | AllUniProt

Conditions LETM1 is implicated in, by any mechanism.

  • Neurodegeneration, childhood-onset, with multisystem involvement due to mitochondrial dysfunction (CONDMIM) MIM:620089

Disease | GeneticClinVar

10 pathogenic / likely-pathogenic of 347 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • LETM1-associated clinical spectrum with predominant nervous system involvement
  • Neurodegeneration, childhood-onset, with multisystem involvement due to mitochondrial dysfunction

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)
0.74
gnomAD pLI
0
gnomAD missense Z
1.58
DepMap mean gene effect
-0.75
DepMap dependency class
common

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

InteractionsUniProt · HPA

Protein binding partners of LETM1 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 LETM1 as an antibody target. Whether an autoantibody or antibody against LETM1 could matter depends on whether native LETM1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

LETM1 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 LETM1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/LETM1. 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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