Serine protease that plays a key role in innate immunity in response to Gram-positive bacterial and fungal proteases (PubMed:12098703, PubMed:18724373, PubMed:16399077). Acts as a component of the Toll pathway upstream of protease spz processing enzyme SPE and Tl ligand spz (PubMed:12098703, PubMed:18724373, PubMed:16399077). Nec regulates the cascade by inhibiting psh (PubMed:12098703). The clip domain consists of 35-55 residues which are 'knitted' together usually by 3 conserved disulfide bonds forming a clip-like compact structure. Increased susceptibility to fungal infection and failure to induce the expression of antifungal peptide Drs in response to fungal infection but not in response to E.coli or M.luteus bacterial infection. Belongs to the peptidase S1 family. CLIP subfamily.