Figure 5

Regulation of cellulase gene transcription by GNA1. Transcription of the major cellulase cbh1 upon cultivation in constant light (LL) in the wild-type strain, gna1QL and in Δgna1 upon growth in constant light or constant darkness with cellulose as carbon source. Mycelia were grown in Mandels-Andreotti medium supplemented with 1% microcrystalline cellulose as carbon source in constant light (1,800 lux, 25 μmol photons m^-2 s^-1), indicated by LL, or constant darkness (DD) and harvested after 72 and 96 h. For northern blotting, 20 μg of total RNA were loaded per lane and [α³²P]-radiolabeled PCR fragments of cbh1 and 18S rRNA were used as probes.