Seroatlas · Human Serome Atlas

MRPL9

Large ribosomal subunit protein bL9m

Also known as: RM09_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q9BYD2
Gene
MRPL9
Ensembl
ENSG00000143436
Chromosome
1
Canonical length
267 aa
Protein class
Predicted intracellular proteins, Ribosomal proteins
Subcellular location
Mitochondria

OverviewNCBI Gene

This is a nuclear gene encoding a protein component of the 39S subunit of the mitochondrial ribosome. Alternative splicing results in multiple transcript variants. A pseudogene of this gene is found on chromosome 8. [provided by RefSeq, Jul 2014]

Canonical amino-acid sequenceUniProt

267 residues, UniProt reviewed canonical sequence.

>Q9BYD2|MRPL9
     1  MAAPVVTAPG RALLRAGAGR LLRGGVQELL RPRHEGNAPD LACNFSLSQN RGTVIVERWW
    61  KVPLAGEGRK PRLHRRHRVY KLVEDTKHRP KENLELILTQ SVENVGVRGD LVSVKKSLGR
   121  NRLLPQGLAV YASPENKKLF EEEKLLRQEG KLEKIQTKAG EATVKFLKSC RLEVGMKNNV
   181  KWELNPEIVA RHFFKNLGVV VAPHTLKLPE EPITRWGEYW CEVTVNGLDT VRVPMSVVNF
   241  EKPKTKRYKY WLAQQAAKAM APTSPQI

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against MRPL9 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)
0.46
Highest tissue expression
67 nTPM

Expression across tissuesHPA

Tissue

  • skeletal muscle: 67 nTPM
  • tongue: 52 nTPM
  • parathyroid gland: 46 nTPM
  • thymus: 43 nTPM
  • bone marrow: 39 nTPM
  • kidney: 38 nTPM

Single-cell type

  • extravillous trophoblasts: 144 nCPM
  • migrating cytotrophoblasts: 129 nCPM
  • esophageal basal cells: 126 nCPM
  • cytotrophoblasts: 114 nCPM
  • early spermatids: 111 nCPM
  • esophageal suprabasal cells: 109 nCPM

Immune cell

  • T-reg: 122 nTPM
  • myeloid DC: 99 nTPM
  • memory B-cell: 97 nTPM
  • memory CD8 T-cell: 96 nTPM
  • MAIT T-cell: 95 nTPM
  • memory CD4 T-cell: 95 nTPM

Brain region

  • cerebellum: 26 nTPM
  • hypothalamus: 26 nTPM
  • cerebral cortex: 24 nTPM
  • white matter: 24 nTPM
  • medulla oblongata: 24 nTPM
  • spinal cord: 24 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)
1.05
gnomAD pLI
0
gnomAD missense Z
0.26
DepMap mean gene effect
-0.47
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 16% 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 bL9/RNase H1, N-terminal
  • Large ribosomal subunit protein bL9
  • Large ribosomal subunit protein bL9, N-terminal
  • Large ribosomal subunit protein bL9, N-terminal domain superfamily
  • Large ribosomal subunit protein bL9m, C-terminal domain
  • Large ribosomal subunit protein bL9m, N-terminal domain
  • Ribosomal protein L9, N-terminal domain
  • Large ribosomal subunit protein bL9m C-terminal domain
  • Large ribosomal subunit protein bL9m N-terminal domain

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of MRPL9 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 MRPL9 as an antibody target. Whether an autoantibody or antibody against MRPL9 could matter depends on whether native MRPL9 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

MRPL9 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 MRPL9 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/MRPL9. 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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