Secreted effector required for virulence (PubMed:21692877, PubMed:23459172). Functions as an inhibitor of a set of apoplastic maize papain-like cysteine proteases (PLCPs) including CP1A, CP1B, XCP2 and CP2, whose activity is directly linked with salicylic-acid-associated plant defenses (PubMed:23459172). Acts as a substrate mimicking molecule for apoplastic PLCPs and its processing releases the embedded inhibitor peptide PID14, which in turn blocks PLCPs to modulate host immunity (PubMed:30952847). Interacts with host cysteine proteases CP1A, CP1B, XCP2 and CP2. Secreted to the biotrophic interface. Expression is highly up-regulated during all stages of pathogenic development (PubMed:21692877). Expression is positively regulated by the unfolded protein response (UPR) signaling via the binding of CIB1 to the UPRE motif localized at the PIT1/PIT2 promoter (PubMed:27093436). The PID14 protease inhibitor domain is sufficient for inhibition of host cysteine proteases. Cleaved by host target papain-like cysteine proteases (PLCPs) to release the embedded inhibitor peptide PID14. Keeps the ability to penetrate maize epidermis and to grow intracellularly at sites of infection but fails to spread and induce tumors in infected leaves.