Keratin 18 is a

type I cytokeratin Type I keratins (or Type I cytokeratins) are cytokeratins that constitute the Type I intermediate filaments (IFs) of the intracytoplasmatic cytoskeleton, which is present in all mammalian epithelial cells. Most of the type I keratins consist of aci ...

. It is, together with its filament partner

keratin 8 Keratin, type II cytoskeletal 8 also known as cytokeratin-8 (CK-8) or keratin-8 (K8) is a keratin protein that is encoded in humans by the ''KRT8'' gene. It is often paired with keratin 18. Utility as an immunohistochemical stain Antibodies to CK ...

, perhaps the most commonly found products of the

intermediate filament Intermediate filaments (IFs) are cytoskeletal structural components found in the cells of vertebrates, and many invertebrates. Homologues of the IF protein have been noted in an invertebrate, the cephalochordate ''Branchiostoma''. Intermedia ...

gene family. They are expressed in single layer

epithelial tissue Epithelium or epithelial tissue is one of the four basic types of animal tissue, along with connective tissue, muscle tissue and nervous tissue. It is a thin, continuous, protective layer of compactly packed cells with a little intercellu ...

s of the body. Mutations in this gene have been linked to cryptogenic

cirrhosis Cirrhosis, also known as liver cirrhosis or hepatic cirrhosis, and end-stage liver disease, is the impaired liver function caused by the formation of scar tissue known as fibrosis due to damage caused by liver disease. Damage causes tissue repai ...

. Two transcript variants encoding the same protein have been found for this gene. Keratin 18 is often used together with

and

keratin 19 Keratin, type I cytoskeletal 19 also known as cytokeratin-19 (CK-19) or keratin-19 (K19) is a 40 kDa protein that in humans is encoded by the ''KRT19'' gene. Keratin 19 is a type I keratin. Function Keratin 19 is a member of the keratin family. ...

to differentiate cells of epithelial origin from hematopoietic cells in tests that enumerate

circulating tumor cell A circulating tumor cell (CTC) is a cell that has shed into the vasculature or lymphatics from a primary tumor and is carried around the body in the blood circulation. CTCs can extravasate and become ''seeds'' for the subsequent growth of additional ...

s in blood.

Interactions

Keratin 18 has been shown to

interact Advocates for Informed Choice, dba interACT or interACT Advocates for Intersex Youth, is a 501(c)(3) nonprofit organization using innovative strategies to advocate for the legal and human rights of children with intersex traits. The organizati ...

with Collagen, type XVII, alpha 1,

DNAJB6 DnaJ homolog subfamily B member 6 is a protein that in humans is encoded by the ''DNAJB6'' gene. Function This gene encodes a member of the DNAJ protein family. DNAJ family members are characterized by a highly conserved amino acid stretch cal ...

Pinin Pinin is a protein that in humans is encoded by the ''PNN'' gene. Interactions Pinin has been shown to interact with Keratin 8, Keratin 18, Keratin 19, CTBP1, RNPS1, PRPF4B, SFRS4 Splicing factor, arginine/serine-rich 4 is a protein that in h ...

and

TRADD Tumor necrosis factor receptor type 1-associated DEATH domain protein is a protein that in humans is encoded by the ''TRADD'' gene. TRADD is an adaptor protein. Function The protein encoded by this gene is a death domain containing adaptor m ...

Interactions

References

Further reading