Intracellular Staining by Flow Cytometry
|Detection of Furin in H9 Human Cell Line by Flow Cytometry. H9 human cutaneous T lymphoma cell line was stained with Mouse Anti-Human Furin APC‑conjugated Monoclonal Antibody (Catalog # IC1503A, filled histogram) or isotype control antibody (Catalog # IC0041A, open histogram). To facilitate intracellular staining, cells were fixed with Flow Cytometry Fixation Buffer (Catalog # FC004) and permeabilized with Flow Cytometry Permeabilization/Wash Buffer I (Catalog # FC005). View our protocol for Staining Intracellular Molecules.|
Furin is a member of the Proprotein Convertase (PC) family, which belongs to the subtilisin superfamily of serine proteases (1-3). As a cellular protease, Furin processes a variety of proproteins in secretory pathway compartments by cleaving after Arg-Xaa-Lys/Arg-Arg-like motifs, which usually reside at the end of the pro regions of these proproteins. Examples of the proprotein substrates are growth factors and receptors, extracellular matrix proteins, and other proteases. Furin has an essential role in embryogenesis and homeostasis and is implicated in various pathologies such as cancer, neurodegenerative diseases and anthrax. It is synthesized as a 794 amino acid (aa) type I transmembrane protein precursor with a signal peptide (aa residues 1-24), a pro region (aa residues 25-107 which play a crucial role in the folding, activation and transport of Furin) and a mature chain (aaresidues 108-794). The mature chain consists of the subtilisin-like catalytic domain, a P domain which is essential for enzyme activity and the modulation of pH and calcium requirements, and a cytoplasmic domain which controls the localization and sorting of Furin in the trans-Golgi network/endosomal system. The purified recombinant human Furin (residues 108-715) corresponds to the mature enzyme that terminates before the transmembrane domain. Over aa 108-715, human and mouse Furin share 95% aa sequence identity (1-3).