RCN3 contains five Arg-Xaa-Xaa-Arg motifs, which serve as target sequences for subtilisin-like proprotein convertases (SPCs). SPCs are a family of serine endoproteases that proteolytically activate proproteins. One notable member of this family is PACE4 (Paired Basic Amino Acid Cleaving Enzyme 4), whose synthesis is influenced by the association and coexpression with RCN3 .
The protein is transiently associated with proPACE4 but not with mature PACE4. Inhibition of PACE4 maturation by a calcium ionophore results in the accumulation of the proPACE4-RCN3 complex in cells. This selective and transient association of RCN3 with the precursor of PACE4 is proposed to play a significant role in the biosynthesis of PACE4 .
Recombinant human RCN3 protein is typically expressed in E. coli or HEK293 cells and purified using conventional chromatography techniques. The recombinant protein often includes a His-tag at the N-terminus or C-terminus to facilitate purification. The protein is then subjected to various analyses, including SDS-PAGE, to confirm its purity and molecular weight .
RCN3 is used in various research applications, including studies on calcium-binding proteins, secretory pathways, and proprotein convertases. Its role in the biosynthesis of PACE4 makes it a valuable tool for understanding the mechanisms of proteolytic activation and the regulation of proprotein convertases .
Recombinant RCN3 protein is typically stored at -20°C to -80°C under sterile conditions to maintain its stability. It is recommended to aliquot the protein to avoid repeated freeze-thaw cycles, which can degrade the protein. The lyophilized form of the protein is stable for up to twelve months from the date of receipt .