Cathepsin B
Cathepsin B (CTSB) is a lysosomal cysteine protease of the peptidase C1 family. It is believed to take part in intracellular protein degradation and turnover, and is also known as amyloid precursor protein secretase. Browse Assay Genie's current range of Cathepsin B research reagents below, or read on for the biology behind the target.
Cathepsin B is a thiol protease believed to participate in the intracellular degradation and turnover of proteins. It has both endopeptidase and exopeptidase activity. Among its reported substrates is matrix extracellular phosphoglycoprotein (MEPE), which it cleaves. It is also involved in solubilising cross-linked thyroglobulin (TG) in the thyroid follicle lumen. Beyond its lysosomal role, it has been implicated in tumour invasion and metastasis.
The CTSB gene encodes a member of the C1 family of peptidases, and alternative splicing produces multiple transcript variants. At least one variant encodes a preproprotein that is proteolytically processed into several products, including the cathepsin B light and heavy chains. These chains can dimerise to form the double-chain form of the enzyme. UniProt lists the protein in the lysosome, melanosome, extracellular space and apical cell membrane. The gene group classification places it with the cathepsins, elastases and cysteine endopeptidases. Mouse and rat each have a Ctsb ortholog, and multiple pseudogenes of the human gene have been identified.
Cathepsin B is also known as amyloid precursor protein secretase and is involved in the proteolytic processing of amyloid precursor protein (APP). Incomplete processing of APP has been suggested as a causative factor in Alzheimer's disease. Overexpression of the protein has been associated with oesophageal adenocarcinoma and other tumours. Together with cathepsin L, cathepsin B is involved in cleaving the SARS-CoV-2 spike protein when the virus enters human host cells.
Cathepsin B is a lysosomal cysteine protease thought to contribute to intracellular protein degradation and turnover.
The protease has been implicated in tumour invasion and metastasis, and its overexpression is associated with oesophageal adenocarcinoma and other tumours.
Cathepsin B acts as an APP secretase, and incomplete APP processing has been suggested as a causative factor in Alzheimer's disease.
Cathepsin B and cathepsin L both take part in cleaving the SARS-CoV-2 spike protein during entry into host cells.
Cathepsin B is a thiol protease believed to participate in intracellular protein degradation and turnover. It cleaves MEPE, helps solubilise cross-linked thyroglobulin in the thyroid follicle lumen, and has been implicated in tumour invasion and metastasis. It shows both endopeptidase and exopeptidase activity.
Not only. At least one transcript variant encodes a preproprotein that is proteolytically processed into several products, including light and heavy chains. These can dimerise to form the double-chain form of the enzyme. Alternative splicing of the gene yields multiple transcript variants.
Cathepsin B is linked to Alzheimer's disease through APP processing, and its overexpression is associated with oesophageal adenocarcinoma and other tumours. Mouse and rat both carry a Ctsb ortholog. Check the datasheet of any product for its validated reactivity.
Other cathepsins, amyloid precursor protein and further targets linked to lysosomal proteolysis and cancer biology.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P07858; product specifications from Assay Genie datasheets.