Putative catalytic subunit of a class II histone deacetylase complex%3B role in azole resistance via Hsp90p%2C and in the heat shock response%3B Hda1p interacts with the Hda2p-Hda3p subcomplex to form an active tetramer%3B deletion increases histone H2B%2C H3 and H4 acetylation%3B other members of the HDA1 histone deacetylase complex are Hda2p and Hda3p