FIG. 3.

gna3 transcription is enhanced by light. (A) Mycelia of the wild-type strain TU-6 and of the env1^PAS− and gna3QL mutant strains were cultivated in Mandels-Andreotti medium with 1% (wt/vol) microcrystalline cellulose as the sole carbon source in constant darkness (DD) or constant light (LL). Twenty micrograms of total RNA was loaded per lane, and an α-³²P-radiolabeled PCR fragment spanning the cDNA of gna3 was used as a probe. 18S rRNA was used as control. (B) The short-term light response of gna3 was analyzed in the wild-type strain QM9414 and the env1^PAS− mutant strain upon growth in Mandels-Andreotti medium with 1% (wt/vol) glycerol as a carbon source in constant darkness (DD) and after 30, 60, 120, and 240 min of illumination (DL). Twenty micrograms of total RNA was loaded per lane, and an α-³²P-radiolabeled PCR fragment spanning the cDNA of gna3 was used as a probe. Results were quantified, and the amount of light-induced transcription of gna3 in the specified strain was normalized to the 18S rRNA control hybridization. Graphs show transcription levels above background.