PTPN18

Protein identityUniProt · HPA

UniProt accession

Q99952

Gene

PTPN18

Ensembl

ENSG00000072135

Chromosome

2

Canonical length

460 aa

Protein class

Enzymes, Predicted intracellular proteins

Subcellular location

Intermediate filaments

OverviewNCBI Gene

The protein encoded by this gene is a member of the protein tyrosine phosphatase (PTP) family. PTPs are known to be signaling molecules that regulate a variety of cellular processes including cell growth, differentiation, the mitotic cycle, and oncogenic transformation. This PTP contains a PEST motif, which often serves as a protein-protein interaction domain, and may be related to protein intracellular half-live. This protein can differentially dephosphorylate autophosphorylated tyrosine kinases that are overexpressed in tumor tissues, and it appears to regulate HER2, a member of the epidermal growth factor receptor family of receptor tyrosine kinases. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Nov 2008]

Canonical amino-acid sequenceUniProt

460 residues, UniProt reviewed canonical sequence.

>Q99952|PTPN18
     1  MSRSLDSARS FLERLEARGG REGAVLAGEF SDIQACSAAW KADGVCSTVA GSRPENVRKN
    61  RYKDVLPYDQ TRVILSLLQE EGHSDYINGN FIRGVDGSLA YIATQGPLPH TLLDFWRLVW
   121  EFGVKVILMA CREIENGRKR CERYWAQEQE PLQTGLFCIT LIKEKWLNED IMLRTLKVTF
   181  QKESRSVYQL QYMSWPDRGV PSSPDHMLAM VEEARRLQGS GPEPLCVHCS AGCGRTGVLC
   241  TVDYVRQLLL TQMIPPDFSL FDVVLKMRKQ RPAAVQTEEQ YRFLYHTVAQ MFCSTLQNAS
   301  PHYQNIKENC APLYDDALFL RTPQALLAIP RPPGGVLRSI SVPGSPGHAM ADTYAVVQKR
   361  GAPAGAGSGT QTGTGTGTGA RSAEEAPLYS KVTPRAQRPG AHAEDARGTL PGRVPADQSP
   421  AGSGAYEDVA GGAQTGGLGF NLRIGRPKGP RDPPAEWTRV

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against PTPN18 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)

0.4

Highest tissue expression

62 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)

0.98

gnomAD pLI

0

gnomAD missense Z

0.33

DepMap mean gene effect

-0.05

DepMap dependency class

selective

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

• blastocyst formation
• negative regulation of ERBB signaling pathway
• protein dephosphorylation

Molecular functions

• non-membrane spanning protein tyrosine phosphatase activity
• protein tyrosine phosphatase activity

Cellular components

• cytoplasm
• cytosol
• nucleoplasm
• nucleus

Protein domainsUniProt · Pfam · InterPro

• Tyrosine-specific protein phosphatase, PTPase domain
• Tyrosine-specific protein phosphatases domain
• Protein-tyrosine phosphatase, catalytic
• Protein-tyrosine phosphatase, active site
• Protein-tyrosine phosphatase-like
• Tyrosine-protein phosphatase non-receptor type 12/18/22
• Protein-tyrosine phosphatase
• Tyrosine-protein phosphatase non-receptor type 18, catalytic domain

KeywordsUniProt

• Cytoplasm
• Hydrolase
• Nucleus
• Phosphoprotein
• Protein phosphatase

InteractionsUniProt · HPA

Protein binding partners of PTPN18 in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

• PSTPIP1
• EGFR