cornulin (tumor-related protein, squamous epithelial heat shock protein 53, 53 kD squamous epithelial-induced stress protein, 58 kD heat shock protein, 53 kD putative Ca+2-binding protein, CRNN, c1orf10, DRC1, PDRC1, SEP53)

Function: - survival factor that participates in the clonogenicity of squamous esophageal epithelium cell lines, attenuates deoxycholic acid (DCA)-induced apoptotic cell death & release of Ca⁺² - when overexpressed in oral squamous carcinoma cell lines, regulates negatively cell proliferation by the induction of G1 arrest Cofactor: - binds Ca⁺² with an affinity similar to that of the S100 proteins Structure: - homodimer - EF-hand is necessary for the colony survival activity to protect cells from death induced by exposure to DCA - belongs to the S100-fused protein family - contains 1 EF-hand domain Compartment: - cytoplasm - does not colocalize with TGM1 Expression: - squamous epithelia cell-specific - expressed in the esophagus (periphery of the cells of the granular & the upper spinous layers), foreskin (granular & lower cornified cells), scalp skin (granular layer), inner root sheath of the hair follicle & in primary keratinocytes (at protein level) - expressed in the squamous epithelium of the cervix, esophagus, foreskin & larynx - expressed in the fetal bladder & scalp skin - expressed at very low levels in the lung, kidney, uterus, skeletal muscle, heart & fetal brain - up-regulated after heat shock, ponasterone A & deoxycholic acid Pathology: - undetectable or barely detectable in esophageal & oral squamous cell carcinoma compared with the matched adjacent normal esophageal mucosa - undetectable or barely detectable in larynx & esophagus from patients with pH-documented laryngopharyngeal reflux

General

Ca+2 binding protein phosphoprotein

Properties

SIZE: entity length = 495 aa MW = 54 kD MOTIF: EF hand SITE: 49-84 MOTIF: Ca+2-binding site SITE: 62-73 glutamine-rich region {139-389} MOTIF: glutamine residue (SEVERAL) Thr phosphorylation site {T398} Thr phosphorylation site {T406}

Database Correlations

UniProt Q9UBG3 PFAM correlations

References

UniProt :accession Q9UBG3