ALLN, cysteine proteinase inhibitor

Supplementary information

This supplementary information is collated from multiple sources and compiled automatically.

Cathepsin B also known as CTSB or APP secretase is a protein encoded by the CTSB gene. It functions as a cysteine protease and plays a role in the degradation of proteins within the lysosome. The molecular mass of Cathepsin B is approximately 37 kDa. This enzyme is expressed in many tissues notably in the liver and the pancreas as well as in fibroblasts. As a cysteine protease Cathepsin B cleaves peptide bonds facilitating protein turnover and cellular maintenance.

Biological function summary

Cathepsin B contributes significantly to proteolytic processes mainly within the lysosomes and is part of the protein degradation pathway. It is not known to be part of a complex but it interacts dynamically with other enzymes involved in cellular remodeling and autophagy. Cathepsin B's enzyme activity is important for cellular homeostasis and responding to cellular stress.

Pathways

Cathepsin B integrates into the autophagy and apoptosis pathways. Its involvement in the lysosomal degradation process is essential for cellular adaptation to varying physiological and pathological conditions. In the apoptosis pathway the enzyme interacts with caspases promoting apoptosis under certain stress conditions. Cathepsin B also shares functional relationships with other proteolytic enzymes such as Cathepsin L which contributes similarly to protein degradation.

Cathepsin B is linked with cancer progression and Alzheimer's disease. In cancer overexpression leads to increased invasive potential of tumor cells interacting with other proteases like matrix metalloproteinases (MMPs). In Alzheimer's disease Cathepsin B participates in the formation of amyloid-beta plaques where its interaction with proteins such as amyloid precursor protein (APP) is significant. Understanding these interactions helps to explore therapeutic approaches targeting Cathepsin B's role in these conditions.