Rat Cathepsin B HEK293 Overexpression Lysate 产品信息
Product Description
This Rat Cathepsin B overexpression lysate was created in HEK293 Cells and intented for use as a Western blot (WB) positive control. Purification of Cathepsin B protein (Cat: 80545-R08H) from the overexpression lysate was verified.
Expression Host
HEK293 Cells
Sequence Information
A DNA sequence encoding the rat Ctsb (NP_072119.2) (Met1-Phe339) was expressed with a polyhistidine tag at the C-terminus.
Molecule Mass
The recombinant rat Ctsb consists 333 amino acids and predicts a molecular mass of 37.1 kDa.
Rat Cathepsin B HEK293 Overexpression Lysate Usage Guide
Preparation Method
Cell lysate was prepared by homogenization of the over-expressed cells in ice-cold modified RIPA Lysis Buffer with cocktail of protease inhibitors (Sigma). Cell debris was removed by centrifugation. Protein concentration was determined by Bradford assay (Bio-Rad protein assay, Microplate Standard assay). The cell lysate was boiled for 5 min in 1 x SDS loading buffer (50 mM Tris-HCl pH 6.8, 12.5% glycerol, 1% sodium dodecylsulfate, 0.01% bromophenol blue) containing 5% b-mercaptoethanol, and lyophilized.
Lysis Buffer
Modified RIPA Lysis Buffer: 50 mM Tris-HCl pH 7.4, 150 mM NaCl, 1mM EDTA, 1% Triton X-100, 0.1% SDS, 1% Sodium deoxycholate, 1mM PMSF.
Recommend Usage
1. Centrifuge the tube for a few seconds and ensure the pellet at the bottom of the tube. 2. Re-dissolve the pellet using 200μL pure water and boil for 2-5 min.
Sample Buffer
1 X Sample Buffer (1 X modified RIPA buffer+1 X SDS loading buffer).
Stability & Storage
Store at 4℃ for up to twelve months from date of receipt. After re-dissolution, aliquot and store at -80℃ for up to twelve months. Avoid repeated freeze-thaw cycles.
Application
Western Blot (WB)
Optimal dilutions/concentrations should be determined by the end user.
Cathepsin B Background Information
Cathepsin B is a papain-family cysteine protease that is normally located in lysosomes, where it is involved in the turnover of proteins and plays various roles in maintaining the normal metabolism of cells. This protease has been implicated in pathological conditions, e.g., tumor progression and arthritis. In disease conditions, increases in the expression of cathepsin B occur at both the gene and protein levels. Cathepsin B is synthesized as a preproenzyme and the primary pathways for its normal trafficking to the lysosome utilize mannose 6-phosphate receptors (MPRs). Mature cathepsin B has the ability to degrade several extracellular matrix components at both neutral and acidic pH and has been implicated in the progression of several human and rodent tumors progression and arthritis. Cathepsin B expression is increased in many human cancers at the mRNA, protein and activity levels. It is also frequently overexpressed in premalignant lesions, an observation that associates this protease with local invasive stages of cancer. Increased expression of cathepsin B in primary cancers, and especially in preneoplastic lesions, suggests that this enzyme might have pro-apoptotic features. Active cathepsin B is also secreted from tumours, a mechanism likely to be facilitated by lysosomal exocytosis or extracellular processing by surface activators. Cathepsin B is localized to caveolae on the tumour surface, where binding to the annexin II heterotetramer occurs. Thus CTSB is suggested as a tumor marker. Additionally, Cathepsin B can degrade extracellular matrix proteins, such as collagen IV and laminin, and can activate the precursor form of urokinase plasminogen activator (uPA), perhaps thereby initiating an extracellular proteolytic cascade.
References
Mai J, et al. (2000) Cell surface complex of cathepsin B/annexin II tetramer in malignant progression. Biochim Biophys Acta. 1477(1-2): 215-30. Podgorski I, et al. (2003) Cathepsin B and its role(s) in cancer progression. Biochem Soc Symp. (70): 263-76. Yan S, et al. (2003) Molecular regulation of human cathepsin B: implication in pathologies. Biol Chem. 384(6): 845-54. Roshy S, et al. (2003) Pericellular cathepsin B and malignant progression. Cancer Metastasis Rev. 22(2-3): 271-86.