Recombinant Proteins
Product List
KRT17 Human
Cytokeratin 17 Human Recombinant
KRT18 Human
Cytokeratin 18 Human Recombinant
KRT18 Human, His
Cytokeratin 18 Human Recombinant , His Tag
KRT19 Human
Cytokeratin 19 Human Recombinant
Introduction
Cytokeratins are a class of keratin proteins found in the intracytoplasmic cytoskeleton of epithelial tissue. They are an important component of intermediate filaments, which help cells resist mechanical stress . Cytokeratins are classified into two main types: acidic (type I) and basic or neutral (type II). Each cytokeratin pair contains both acidic and basic cytokeratins in equimolar amounts . These proteins are numbered in order of decreasing size, from high molecular weight (HMWCKs) to low molecular weight (LMWCKs) .
Cytokeratins exhibit key biological properties, including providing structural support and protecting epithelial cells against mechanical stress . They are expressed in a tissue-specific manner, with different cytokeratins being present in various organs and tissues . For example, cytokeratin 5 is expressed by squamous cells throughout the body, while cytokeratin 7 is found in epithelial cells of the thyroid gland, lungs, and other organs .
Cytokeratins play several primary biological functions, including maintaining the structural integrity of epithelial cells and participating in cell signaling, cell-cell adhesion, and apoptosis . They act as markers of cell proliferation and are involved in the response to stress and preservation of epithelial cell authenticity . Cytokeratins also play a role in immune responses and pathogen recognition by maintaining the barrier function of epithelial tissues .
Cytokeratins interact with other molecules and cells through various mechanisms. They form heterodimeric pairs of acidic and basic subunits, which are further assembled into keratin filaments . These filaments interact with desmosomes and hemidesmosomes, contributing to cell-cell adhesion and the connection between basal cells and the underlying connective tissue . Cytokeratins also participate in signaling pathways, such as the PI3K/Akt and ERK MAPK pathways, modulating intracellular signaling .
The expression and activity of cytokeratins are regulated by several mechanisms, including transcriptional regulation and post-translational modifications . Site-specific phosphorylation plays a crucial role in the assembly and disaggregation of the keratin network, impacting dynamic cellular processes such as mitosis, cell movement, and differentiation . The expression of cytokeratins is also organ-specific and depends on the type of epithelial cells and their degree of differentiation .
Cytokeratins have various applications in biomedical research, diagnostic tools, and therapeutic strategies. They are commonly used as markers to identify and classify different types of epithelial cells, playing a key role in the diagnosis and classification of many types of cancer . Immunohistochemistry (IHC) techniques are used to detect cytokeratin expression in tissue samples, aiding in tumor diagnosis and characterization . Additionally, cytokeratins are being explored as potential therapeutic targets for certain cancers .
Cytokeratins play a significant role throughout the life cycle, from development to aging and disease. They are involved in the differentiation and development of epithelial tissues and contribute to the maintenance of tissue integrity and function . During aging, changes in cytokeratin expression and function can impact tissue homeostasis and contribute to age-related diseases . In disease states, such as cancer, cytokeratins can serve as biomarkers for diagnosis and prognosis .
