Recombinant Human CPB1 protein(Met1-Tyr417), His-tagged

• Cat.No.: CPB1-3175H
• Product Overview: Recombinant Human CPB1 (NP_001862.2) (Met 1-Tyr 417) was expressed in HEK293 with a C-terminal polyhistidine tag.

Specification

• Species: Human
• Source: HEK293
• Tag: His
• Protein Length: 1-417 a.a.
• Form: Lyophilized from sterile 25mM MES, 0.1 M NaCl, pH 6.5. Normally 5 % - 8 % trehalose, mannitol and 0.01% Tween80 are added as protectants before lyophilization.
• Bio-activity: Measured by its ability to cleave a colorimetric peptide substrate, Hippuryl-Arg, as measured using the wavelength at 254 nm. The specific activity is >1000 pmoles/min/μg.
• Molecular Mass: The recombinant human CPB1 consists of 413 amino acids and has a predicted molecular mass of 47 kDa. In SDS-PAGE under reducing conditions, it migrates as an approximately 45 kDa band.
• Endotoxin: < 1.0 EU per μg of the protein as determined by the LAL method
• Purity: > 98 % as determined by SDS-PAGE
• Storage: Samples are stable for up to twelve months from date of receipt at -20°C to -80°C. Store it under sterile conditions at -20°C to -80°C. It is recommended that the protein be aliquoted for optimal storage. Avoid repeated freeze-thaw cycles.
• Reconstitution: It is recommended that sterile water be added to the vial to prepare a stock solution of 0.2 ug/ul. Centrifuge the vial at 4°C before opening to recover the entire contents.

Gene Information

• Gene Name: CPB1 carboxypeptidase B1 (tissue) [ Homo sapiens ]
• Official Symbol: CPB1
• Synonyms: CPB1; carboxypeptidase B1 (tissue); carboxypeptidase B; pancreatic carboxypeptidase B; protaminase; tissue carboxypeptidase B; procarboxypeptidase B; pancreas-specific protein; CPB; PASP; PCPB; DKFZp779K1333
• Gene ID: 1360
• mRNA Refseq: NM_001871
• Protein Refseq: NP_001862
• MIM: 114852
• UniProt ID: P15086

Case Study

Case 1: Nakano E, et al. Am J Physiol Gastrointest Liver Physiol. 2015

Changes in the CPA1 gene are linked to early chronic pancreatitis (CP). Researchers explored if CPA2 and CPB1 genes also play a role in CP in Japan and Germany by sequencing these genes in over 900 patients. Various nonsynonymous variants in CPA2 and CPB1 were found, with some showing significant loss of function. Despite this, none of these variants were more common in CP patients, suggesting CPA2 and CPB1 aren't linked to CP.

Fig1. Densitometric quantitation of secreted CPB1 levels.

Fig2. Activity of the CPB1 variants.

Case 2: Kothari C, et al. Cancers (Basel). 2021

Ductal carcinoma in situ (DCIS) can lead to invasive ductal carcinoma (IDC), and distinguishing it from atypical ductal hyperplasia (ADH) is tricky, causing many unnecessary surgeries. Without treatment, 14-60% of DCIS could turn into IDC, so finding a clear gene marker is key. Studies highlighted high carboxypeptidase B1 (CPB1) levels in DCIS, linked to better survival. Losing CPB1 in cells led to invasive traits. CPB1 can predict 90.1% of DCIS cases, making it a valuable tool to tell DCIS apart from ADH or IDC and to guide treatment choices.

Fig1. CPB1 expression pattern in MCF10A cell line series.

Fig2. Effect of CPB1 knockdown on mRNA level of TUBB3.

Application

Recombinant CPB1 protein is gaining attention in cancer research, particularly for its role in identifying different stages of breast cancer. As a key biomarker for DCIS, CPB1 helps doctors assess the risk of DCIS progressing to invasive cancer, allowing for more personalized treatment plans and potentially reducing the need for aggressive interventions when the risk is low. In addition to its cancer-related applications, CPB1 could have broader medical uses due to its influence on cellular behavior. Its role might extend to other conditions where controlling cell growth and differentiation is crucial. By exploring the functions of CPB1, we could discover new ways to tackle various health issues, leading to more precise and effective therapies.

Fig1. Tyrosine nitration of CPB1 in the sinus lining cells of the spleen. (Saurabh Chatterjee, 2009)