MRPS18A

Protein identityUniProt · HPA

UniProt accession

Q9NVS2

Gene

MRPS18A

Ensembl

ENSG00000096080

Chromosome

6

Canonical length

196 aa

Protein class

Predicted intracellular proteins, Ribosomal proteins

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 28S subunit protein that belongs to the ribosomal protein S18P family. The encoded protein is one of three that has significant sequence similarity to bacterial S18 proteins. The primary sequences of the three human mitochondrial S18 proteins are no more closely related to each other than they are to the prokaryotic S18 proteins. A pseudogene corresponding to this gene is found on chromosome 3p. Alternative splicing results in multiple transcript variants.[provided by RefSeq, Jul 2010]

Canonical amino-acid sequenceUniProt

196 residues, UniProt reviewed canonical sequence.

>Q9NVS2|MRPS18A
     1  MAALKALVSG CGRLLRGLLA GPAATSWSRL PARGFREVVE TQEGKTTIIE GRITATPKES
    61  PNPPNPSGQC PICRWNLKHK YNYDDVLLLS QFIRPHGGML PRKITGLCQE EHRKIEECVK
   121  MAHRAGLLPN HRPRLPEGVV PKSKPQLNRY LTRWAPGSVK PIYKKGPRWN RVRMPVGSPL
   181  LRDNVCYSRT PWKLYH

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against MRPS18A 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)

0.48

Highest tissue expression

134 nTPM

Expression across tissuesHPA

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)

1.34

gnomAD pLI

0

gnomAD missense Z

0.11

DepMap mean gene effect

-0.58

DepMap dependency class

common

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 7% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

• mitochondrial translation
• translation

Molecular functions

• small ribosomal subunit rRNA binding
• structural constituent of ribosome

Cellular components

• mitochondrial inner membrane
• mitochondrial large ribosomal subunit
• mitochondrial small ribosomal subunit
• mitochondrion

Protein domainsUniProt · Pfam · InterPro

• Small ribosomal subunit protein bS18
• Small ribosomal subunit protein bS18 superfamily
• Ribosomal protein S18

KeywordsUniProt

• Mitochondrion
• Ribonucleoprotein
• Ribosomal protein
• Transit peptide

InteractionsUniProt · HPA

Protein binding partners of MRPS18A in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

• MRPL15
• MRPL18
• MRPL27
• MRPL38
• MRPL50
• MRPL53
• MRPL9
• NGRN
• TRUB2