Transcription factor; part of the gene cluster that mediates the biosynthesis of iso-A82775C, a enylepoxycyclohexane and biosynthetic precursor of the chloropestolide anticancer natural products. Iso-A82775C is a precursor for the biosynthesis of the anticancer natural products chloropestolides A to E via a Diesls-Alder reaction with maldoxin (PubMed:29384350). In the absence of the prenyltransferase iacE, siccayne accumulates instead of iso-A82775C and can also be condensed with maldoxin to produce chloropestolides H to K, which show also antibacterial and anticancer properties (PubMed:29384350).