PCSK4

This gene encodes a member of the subtilisin-like proprotein convertase family, which includes proteases that process protein and peptide precursors trafficking through regulated or constitutive branches of the secretory pathway. The encoded protein undergoes an initial autocatalytic processing event in the ER to generate a heterodimer which exits the ER and sorts to subcellular compartments where a second autocatalytic even takes place and the catalytic activity is acquired. This gene encodes one of the seven basic amino acid-specific members which cleave their substrates at single or paired basic residues. The protease is expressed only in the testis, placenta, and ovary. It plays a critical role in fertilization, fetoplacental growth, and embryonic development and processes multiple prohormones including pro-pituitary adenylate cyclase-activating protein and pro-insulin-like growth factor II.

Full Name

Proprotein Convertase Subtilisin/Kexin Type 4

Function

Proprotein convertase involved in the processing of hormone and other protein precursors at sites comprised of pairs of basic amino acid residues (By similarity).
In males, important for ADAM2 processing as well as other acrosomal proteins with roles in fertilization and critical for normal fertilization events such as sperm capacitation, acrosome reaction and binding of sperm to zona pellucida (By similarity).
Plays also a role in female fertility, involved in the regulation of trophoblast migration and placental development, may be through the proteolytical processing and activation of proteins such as IGF2 (PubMed:16040806).
May also participate in folliculogenesis in the ovaries (By similarity).

Biological Process

Acrosome reactionISS:UniProtKB
Binding of sperm to zona pellucidaISS:UniProtKB
FertilizationISS:UniProtKB
Peptide hormone processingManual Assertion Based On ExperimentIBA:GO_Central
Protein processingManual Assertion Based On ExperimentIDA:UniProtKB
Reproductive processISS:UniProtKB
Sperm capacitationISS:UniProtKB

Cellular Location

Membrane
Cytoplasmic vesicle, secretory vesicle, acrosome membrane

Topology

Helical: 709-729

PTM

N-glycosylated.
Synthesized in the endoplasmic reticulum as a zymogen, is matured by autocatalytic cleavage between the prodomain and the catalytic domain.