Description: Homo sapiens keratin 18 (KRT18), transcript variant 1, mRNA. RefSeq Summary (NM_000224): 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]. Transcript (Including UTRs) Position: hg19 chr12:53,342,843-53,346,685 Size: 3,843 Total Exon Count: 7 Strand: + Coding Region Position: hg19 chr12:53,342,958-53,346,626 Size: 3,669 Coding Exon Count: 7
ID:K1C18_HUMAN DESCRIPTION: RecName: Full=Keratin, type I cytoskeletal 18; AltName: Full=Cell proliferation-inducing gene 46 protein; AltName: Full=Cytokeratin-18; Short=CK-18; AltName: Full=Keratin-18; Short=K18; 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. SUBUNIT: Heterotetramer of two type I and two type II keratins. KRT18 associates with KRT8. Interacts with the thrombin- antithrombin complex (By similarity). Interacts with PNN, HCV core protein and mutated CFTR. Interacts with YWHAE, YWHAH and YWHAZ only when phosphorylated. Interacts with DNAJB6, TCHP and TRADD. INTERACTION: O75190:DNAJB6; NbExp=6; IntAct=EBI-297888, EBI-1053164; Q9Y6K9:IKBKG; NbExp=3; IntAct=EBI-297888, EBI-81279; P05787:KRT8; NbExp=8; IntAct=EBI-297888, EBI-297852; Q15628:TRADD; NbExp=11; IntAct=EBI-297888, EBI-359215; SUBCELLULAR LOCATION: Cytoplasm, perinuclear region. Nucleus, nucleolus. TISSUE SPECIFICITY: Expressed in colon, placenta, liver and very weakly in exocervix. Increased expression observed in lymph nodes of breast carcinoma. INDUCTION: By IL6/interleukin-6. PTM: Phosphorylation at Ser-34 increases during mitosis. Hyperphosphorylated at Ser-53 in diseased cirrhosis liver. Phosphorylation increases by IL-6. PTM: Proteolytically cleaved by caspases during epithelial cell apoptosis. Cleavage occurs at Asp-238 by either caspase-3, caspase-6 or caspase-7. PTM: O-GlcNAcylation increases solubility, and decreases stability by inducing proteasomal degradation. DISEASE: Defects in KRT18 are a cause of cirrhosis (CIRRH) [MIM:215600]. MISCELLANEOUS: There are two types of cytoskeletal and microfibrillar keratin: I (acidic; 40-55 kDa) and II (neutral to basic; 56-70 kDa). SIMILARITY: Belongs to the intermediate filament family. WEB RESOURCE: Name=Human Intermediate Filament Mutation Database; URL="http://www.interfil.org";
The RNAfold program from the Vienna RNA Package is used to perform the secondary structure predictions and folding calculations. The estimated folding energy is in kcal/mol. The more negative the energy, the more secondary structure the RNA is likely to have.
Pfam Domains: PF00038 - Intermediate filament protein
ModBase Predicted Comparative 3D Structure on P05783
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Orthologous Genes in Other Species
Orthologies between human, mouse, and rat are computed by taking the best BLASTP hit, and filtering out non-syntenic hits. For more distant species reciprocal-best BLASTP hits are used. Note that the absence of an ortholog in the table below may reflect incomplete annotations in the other species rather than a true absence of the orthologous gene.
US Server
