Seroatlas · Human Serome Atlas

MRPL42

Large ribosomal subunit protein mL42

Also known as: HSPC204, MRP-L31, MRPL31, MRPS32, PTD007, RM42_HUMAN, RPML31

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

Protein identityUniProt · HPA

UniProt accession
Q9Y6G3
Gene
MRPL42
Ensembl
ENSG00000198015
Chromosome
12
Canonical length
142 aa
Protein class
Predicted intracellular proteins, Ribosomal proteins
Subcellular location
Plasma membrane,Mitochondria

OverviewNCBI Gene

Mammalian mitochondrial ribosomal proteins are encoded by nuclear genes and help in protein synthesis within the mitochondrion. Mitochondrial ribosomes (mitoribosomes) consist of a small 28S subunit and a large 39S subunit. They have an estimated 75% protein to rRNA composition compared to prokaryotic ribosomes, where this ratio is reversed. Another difference between mammalian mitoribosomes and prokaryotic ribosomes is that the latter contain a 5S rRNA. Among different species, the proteins comprising the mitoribosome differ greatly in sequence, and sometimes in biochemical properties, which prevents easy recognition by sequence homology. This gene encodes a protein identified as belonging to both the 28S and the 39S subunits. Alternative splicing results in multiple transcript variants. Pseudogenes corresponding to this gene are found on chromosomes 4q, 6p, 6q, 7p, and 15q. [provided by RefSeq, May 2011]

Canonical amino-acid sequenceUniProt

142 residues, UniProt reviewed canonical sequence.

>Q9Y6G3|MRPL42
     1  MAVAAVKWVM SKRTILKHLF PVQNGALYCV CHKSTYSPLP DDYNCNVELA LTSDGRTIVC
    61  YHPSVDIPYE HTKPIPRPDP VHNNEETHDQ VLKTRLEEKV EHLEEGPMIE QLSKMFFTTK
   121  HRWYPHGRYH RCRKNLNPPK DR

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against MRPL42 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
22 nTPM

Expression across tissuesHPA

Tissue

  • parathyroid gland: 22 nTPM
  • liver: 19 nTPM
  • kidney: 19 nTPM
  • thymus: 18 nTPM
  • colon: 16 nTPM
  • rectum: 16 nTPM

Single-cell type

  • late primary spermatocytes: 598 nCPM
  • early spermatids: 332 nCPM
  • parietal cells: 195 nCPM
  • late spermatids: 184 nCPM
  • gastric progenitor cells: 167 nCPM
  • extravillous trophoblasts: 163 nCPM

Immune cell

  • T-reg: 28 nTPM
  • NK-cell: 27 nTPM
  • memory B-cell: 26 nTPM
  • naive B-cell: 23 nTPM
  • naive CD8 T-cell: 22 nTPM
  • naive CD4 T-cell: 21 nTPM

Brain region

  • cerebellum: 44 nTPM
  • white matter: 43 nTPM
  • choroid plexus: 41 nTPM
  • hypothalamus: 40 nTPM
  • midbrain: 38 nTPM
  • cerebral cortex: 38 nTPM

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)
1.18
gnomAD pLI
0.04
gnomAD missense Z
-0.21
DepMap mean gene effect
-0.38
DepMap dependency class
selective

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

  • Large ribosomal subunit protein mL42
  • Mitochondrial 28S ribosomal protein S32

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of MRPL42 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 MRPL42 as an antibody target. Whether an autoantibody or antibody against MRPL42 could matter depends on whether native MRPL42 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

MRPL42 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 MRPL42 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/MRPL42. 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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