Seroatlas · Human Serome Atlas

MXI1

Max-interacting protein 1

Also known as: bHLHc11, MAD2, MXD2, MXI, MXI1_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P50539
Gene
MXI1
Ensembl
ENSG00000119950
Chromosome
10
Canonical length
228 aa
Protein class
Cancer-related genes, Disease related genes, Human disease related genes, Predicted intracellular proteins, Transcription factors
Subcellular location
Nucleoplasm,Nucleoli,Nucleoli rim,Cytosol

OverviewNCBI Gene

Expression of the c-myc gene, which produces an oncogenic transcription factor, is tightly regulated in normal cells but is frequently deregulated in human cancers. The protein encoded by this gene is a transcriptional repressor thought to negatively regulate MYC function, and is therefore a potential tumor suppressor. This protein inhibits the transcriptional activity of MYC by competing for MAX, another basic helix-loop-helix protein that binds to MYC and is required for its function. Defects in this gene are frequently found in patients with prostate tumors. Three alternatively spliced transcripts encoding different isoforms have been described. Additional alternatively spliced transcripts may exist but the products of these transcripts have not been verified experimentally. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

228 residues, UniProt reviewed canonical sequence.

>P50539|MXI1
     1  MERVKMINVQ RLLEAAEFLE RRERECEHGY ASSFPSMPSP RLQHSKPPRR LSRAQKHSSG
    61  SSNTSTANRS THNELEKNRR AHLRLCLERL KVLIPLGPDC TRHTTLGLLN KAKAHIKKLE
   121  EAERKSQHQL ENLEREQRFL KWRLEQLQGP QEMERIRMDS IGSTISSDRS DSEREEIEVD
   181  VESTEFSHGE VDNISTTSIS DIDDHSSLPS IGSDEGYSSA SVKLSFTS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against MXI1 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)
0.59
Highest tissue expression
136 nTPM

Expression across tissuesHPA

Tissue

  • blood vessel: 136 nTPM
  • spinal cord: 95 nTPM
  • midbrain: 78 nTPM
  • salivary gland: 75 nTPM
  • amygdala: 75 nTPM
  • retina: 74 nTPM

Single-cell type

  • melanocytes: 342 nCPM
  • esophageal apical cells: 317 nCPM
  • erythrocytes: 304 nCPM
  • bergmann glia: 274 nCPM
  • astrocytes: 265 nCPM
  • müller glia: 265 nCPM

Immune cell

  • eosinophil: 9.8 nTPM
  • naive CD4 T-cell: 7.8 nTPM
  • neutrophil: 5.6 nTPM
  • MAIT T-cell: 5.1 nTPM
  • memory CD4 T-cell: 5.1 nTPM
  • non-classical monocyte: 5 nTPM

Brain region

  • white matter: 127 nTPM
  • basal ganglia: 104 nTPM
  • medulla oblongata: 98 nTPM
  • thalamus: 98 nTPM
  • pons: 96 nTPM
  • cerebellum: 94 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about MXI1.

Disease | AllUniProt

Conditions MXI1 is implicated in, by any mechanism.

Disease | GeneticClinVar

5 pathogenic / likely-pathogenic of 73 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)
0.77
gnomAD pLI
0
gnomAD missense Z
1.17
DepMap mean gene effect
0.12
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% 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 MXI1 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 MXI1 as an antibody target. Whether an autoantibody or antibody against MXI1 could matter depends on whether native MXI1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

MXI1 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 MXI1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/MXI1. 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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