This Mouse Kallikrein 7/KLK7 overexpression lysate was created in HEK293 Cells and intented for use as a Western blot (WB) positive control. Purification of Kallikrein 7/KLK7 protein (Cat: 50921-M08H) from the overexpression lysate was verified.
A DNA sequence encoding the mouse KLK7 (Q91VE3) (Met1-Arg249) was expressed with a C-terminal polyhistidine tag.
The recombinant mouse KLK7 comprises 239 amino acids and has a predicted molecular mass of 26.5 kDa. The apparent molecular mass of the protein is approximately 31 and 34 kDa in SDS-PAGE under reducing conditions due to glycosylation.
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.
Kallikrein-7, also known as kallikrein-related peptidase 7, Stratum corneum chymotryptic enzyme, Serine protease 6, KLK7, and PRSS6, is a secreted protein that belongs to the peptidase S1 family and Kallikrein subfamily. Members of the Kallikrein family are involved in various malignancies such as prostate (PSA, KLK2, KLK15), ovarian (KLK4, KLK5, KLK6, KLK8, KLK1), and breast cancer (KLK1, KLK13, KLK14). Kallikrein-7 / KLK7 appears to be increased in ovarian cancer and higher KLK7 expression in ovarian cancer tissue is associated with poorer prognosis of ovarian cancer patients. Kallikrein-7 / KLK7 is abundantly expressed in the skin and is expressed by keratinocytes in the epidermis. Kallikrein-7 / KLK7 is up-regulated in ovarian carcinoma, especially late-stage serous carcinoma, compared with normal ovaries and benign adenomas (at the protein level). It was significantly associated with shorter overall survival (OS) and disease-free survival (DFS). Kallikrein-7 / KLK7 may catalyze the degradation of intercellular cohesive structures in the cornified layer of the skin in the continuous shedding of cells from the skin surface. KLK7 also plays a role in the activation of precursors to inflammatory cytokines.
Hansson L., et al.,(1994), Cloning, expression, and characterization of stratum corneum chymotryptic enzyme. A skin-specific human serine proteinase. J. Biol. Chem. 269:19420-19426.
Yousef G.M., et al., (2000), The KLK7 (PRSS6) gene, encoding for the stratum corneum chymotryptic enzyme is a new member of the human kallikrein gene family -- genomic characterization, mapping, tissue expression and hormonal regulation.Gene 254:119-128.
Gan L., et al.,(2000), Sequencing and expression analysis of the serine protease gene cluster located in chromosome 19q13 region.Gene 257:119-130.