KRT18
KRT18 encodes the type I intermediate filament chain keratin 18. Keratin 18, together with its filament partner keratin 8, are perhaps the most commonly found members of the intermediate filament gene family. They are expressed in single layer epithelial tissues of the body. Mutations in this gene have been linked to cryptogenic cirrhosis. Two transcript variants encoding the same protein have been found for this gene. [provided by RefSeq, Jul 2008]
Function
Involved in the uptake of thrombin-antithrombin complexes by hepatic cells (By similarity).
When phosphorylated, plays a role in filament reorganization. Involved in the delivery of mutated CFTR to the plasma membrane. Together with KRT8, is involved in interleukin-6 (IL-6)-mediated barrier protection.
Biological Process
Anatomical structure morphogenesisManual Assertion Based On ExperimentTAS:ProtInc
Cell cycleIEA:UniProtKB-KW
Extrinsic apoptotic signaling pathwayIEA:Ensembl
Golgi to plasma membrane CFTR protein transportManual Assertion Based On ExperimentIDA:UniProtKB
Hepatocyte apoptotic processIEA:Ensembl
Intermediate filament cytoskeleton organizationManual Assertion Based On ExperimentIDA:UniProtKB
Negative regulation of apoptotic processManual Assertion Based On ExperimentIDA:UniProtKB
Tumor necrosis factor-mediated signaling pathwayIEA:Ensembl
Cellular Location
Cytoplasm, perinuclear region
Nucleus, nucleolus
Involvement in disease
Cirrhosis (CIRRH):
A liver disease characterized by severe panlobular liver-cell swelling with Mallory body formation, prominent pericellular fibrosis, and marked deposits of copper. Clinical features include abdomen swelling, jaundice and pulmonary hypertension.
PTM
Phosphorylation at Ser-34 increases during mitosis. Hyperphosphorylated at Ser-53 in diseased cirrhosis liver. Phosphorylation increases by IL-6.
Proteolytically cleaved by caspases during epithelial cell apoptosis. Cleavage occurs at Asp-238 by either caspase-3, caspase-6 or caspase-7.
O-GlcNAcylation increases solubility, and decreases stability by inducing proteasomal degradation.