CSTA

Protein identityUniProt · HPA

UniProt accession

P01040

Gene

CSTA

Ensembl

ENSG00000121552

Chromosome

3

Canonical length

98 aa

Protein class

Cancer-related genes, Disease related genes, Human disease related genes, Plasma proteins, Predicted intracellular proteins

Subcellular location

Nucleoplasm,Cytosol

OverviewNCBI Gene

The cystatin superfamily encompasses proteins that contain multiple cystatin-like sequences. Some of the members are active cysteine protease inhibitors, while others have lost or perhaps never acquired this inhibitory activity. There are three inhibitory families in the superfamily, including the type 1 cystatins (stefins), type 2 cystatins, and kininogens. This gene encodes a stefin that functions as a cysteine protease inhibitor, forming tight complexes with papain and the cathepsins B, H, and L. The protein is one of the precursor proteins of cornified cell envelope in keratinocytes and plays a role in epidermal development and maintenance. Stefins have been proposed as prognostic and diagnostic tools for cancer. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

98 residues, UniProt reviewed canonical sequence.

>P01040|CSTA
     1  MIPGGLSEAK PATPEIQEIV DKVKPQLEEK TNETYGKLEA VQYKTQVVAG TNYYIKVRAG
    61  DNKYMHLKVF KSLPGQNEDL VLTGYQVDKN KDDELTGF

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CSTA 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)

0.33

Highest tissue expression

5,787 nTPM

Expression across tissuesHPA

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about CSTA.

Disease | AllUniProt

Conditions CSTA is implicated in, by any mechanism.

• Peeling skin syndrome 4 (PSS4) MIM:607936

Disease | GeneticClinVar

7 pathogenic / likely-pathogenic of 31 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

• Peeling skin syndrome 4
• CSTA-related disorder

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)

1.92

gnomAD pLI

0

gnomAD missense Z

0.07

DepMap mean gene effect

-0.05

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

• cell-cell adhesion
• keratinocyte differentiation
• negative regulation of proteolysis
• peptide cross-linking

Molecular functions

• cysteine-type endopeptidase inhibitor activity
• protease binding

Cellular components

• cornified envelope
• cytoplasm
• cytosol
• extracellular space
• nucleoplasm
• peptidase inhibitor complex

Protein domainsUniProt · Pfam · InterPro

• Cystatin domain
• Proteinase inhibitor I25A, stefin
• Proteinase inhibitor I25, cystatin, conserved site
• Cystatin superfamily
• Cystatin domain

KeywordsUniProt

• Acetylation
• Cell adhesion
• Cytoplasm
• Ichthyosis
• Protease inhibitor
• Thiol protease inhibitor

InteractionsUniProt · HPA

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

• CTSB
• CTSH
• CTSL