Transcription factor that specifically regulates the expression of the gene cluster that mediates the biosynthesis of the mycotoxin pyrichalasin H, a tyrosine-derived cytochalasan that inhibits the growth of rice seedlings, but also inhibits lymphocyte capping and actin polymerization and alters cell morphology (PubMed:31099577) (Probable). Pyrichalasin H is indicated as the responsible agent for the genus-specific pathogenicity of M.grisea toward crabgrass (PubMed:31099577).