Component of the RPD3C(L) histone deacetylase complex (HDAC). Responsible for the deacetylation of lysine residues on the N-terminal part of the core histones (H2A, H2B, H3 and H4). Histone deacetylation gives a tag for epigenetic repression and plays an important role in transcriptional regulation, cell cycle progression and developmental events (By similarity). Controls filamentous growth and required for full virulence in a mouse model of disseminated candidiasis. Component of the RPD3C(L) complex. Preferentially accumulates in daughter cell nuclei of budding-yeast form to the hyphal tip cells in growing filaments. Expression is controlled by the transcription factor ACE2. Leads to defects in responding to some filament-inducing conditions and to reduced virulence. The ASH1 mRNA is transported to the daughter cell before cytokinesis where translation produces the protein to block mating-type switching, as well as to the hyphal tips during filamentous growth.