NEW TOOLS: RECOMBINANT PROTEASES OF THE RENIN-ANGIOTENSIN SYSTEM (RAS)

The Renin-Angiotensin System (RAS) plays a critical role in maintaining blood pressure homeostasis as well as fluid and salt balance in mammals. Production of angiotensins from angiotensinogen requires the participation and coordination of many proteases in different pathways (Figure 1).^1-7 R&D Systems now offers RAS-related recombinant proteases that can be used in studies of their structure-function relationship and in development of their activators and inhibitors.

Proteases of RAS

Optimization of Chymase Activation

Figure 1. A cascade of proteolytic reactions in RAS results in the generation of different angiotensin (Ang) peptides. Renin cleaves the precursor protein, angiotensinogen, releasing the inactive peptide, angiotensin I. The Carboxypeptidases ACE, ACE2, CMA1, CTSA and CPA3, the aminopeptidases APA and APN, and the endopeptidases CTSG, NEP, THOP1 and NLN participate in various pathways to generate Ang peptides with diverse functions. For example, Ang II and III act as vasoconstrictors whereas Ang1-7 acts as a vasodilator. Active Ang peptides function through their respective receptors, and the same Ang peptides may have different effects through different receptors (not shown).

Figure 2. The conversion of prochymase into active chymase is mediated by recombinant mouse Cathepsin C (Catalog # 2336-CY) in the presence of heparin. The optimal concentrations of heparin and Cathepsin C were obtained by fixing Cathep­sin C (10 µg/mL, top graph) or heparin (0.05 mg/mL, bottom graph).

References

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