Furin Convertase Proteins

Protein Information

Furin is a membrane-associated, calcium-dependent, serine protease that belongs to the subtilisin-like prohormone convertase (PC) family. Members of this family of cellular enzymes cleave most prohormones and neuropeptide precursors. Numerous other cellular proteins, some viral proteins, and bacterial toxins that are transported by the constitutive secretory pathway are also targeted for maturation by PCs. Furin and other PC family members share structural similarities which include a heterogeneous ~10 kDa amino-terminal proregion, a highly conserved ~55 kDa subtilisin-like catalytic domain, and carboxyl-terminal domain that is heterogeneous in length and sequence. These enzymes become catalytically active following proregion cleavage within the appropriate cellular compartment. Furin is the only known PC to possess a transmembrane domain. Cleavage of target proteins occurs at the carboxyl-terminus of the furin consensus sequence, RX(K/R)R. It has been shown that the acidic peptide sequence, C771PSDSEEDEG780, localizes furin to the trans-Golgi-network. Phosphorylation of serine residues within this region modulates intracellular routing of furin protein.