The penicillin regulator PENR1 of Aspergillus nidulans is a HAP-like transcriptional complex.

In Aspergillus nidulans, a DNA-binding complex, PENR1, was shown to bind to two CCAAT-box-containing DNA elements located in the promoter regions of the bidirectionally oriented penicillin biosynthesis genes acvA and ipnA, and of the aat promoter. Here, partial purification of PENR1 and western blotting using anti-HAPC sera indicated that the previously identified HAPC protein, which was suggested to be part of the CCAAT-binding complex AnCF, is also part of PENR1. This was confirmed by band shift assays using protein extracts of a delta hapC strain which exhibited no PENR1 DNA-binding activity.