Serine protease which ensures proper pharyngeal pumping during larval growth by regulating the levels of extracellular matrix component fbl-1 (PubMed:25464847). Independently of its enzymatic activity and probably by acting as a ligand for tyrosine-protein kinase receptor svh-2, involved in axon regeneration after injury by promoting the generation of productive and stable growth cones (PubMed:22388962, PubMed:25464847). May play a role in gonad development (PubMed:25464847). Specifically expressed in ADL sensory neurons. The Kringle domain is dispensable for larval growth and axon regeneration after injury. The PAN domain is required to maintain gonad structure and thus fertility. Dispensable for larval growth. Belongs to the peptidase S1 family.