Transcriptional repressor that binds NRG1 response elements (NRE) of target promoters. Involved in regulation of chlamydospore formation, hyphal growth, virulence, and stress response. Plays a key role in regulating true hyphal growth, but does not regulate pseudohyphal growth in the same fashion. Directs transcriptional repression of a subset of filament-specific genes such as HWP1, HYR1, ALS8, HWP1, or ECE1; via the TUP1 pathway. Functions with UME6 in a negative feedback loop to control the level and duration of filament-specific gene expression in response to inducing conditions. Plays a key role in biofilm formation and dispersion. Also plays the role of a negative regulator of virulence in mice models. Required for the expression of the cell wall genes RBR1. Down-regulated during filament induction and in response to serum at 37 degrees Celsius. Expression of NRG1 is also repressed by RIM101 and under conditions that repress CDC28 expression. The bacterial signaling molecules indole and its derivate indole-3-acetonitrile (IAN) increase NRG1 expression. Exhibits a high degree of filamentous growth and leads to avirulence in a mouse model.