Component of the class 1 Sin3A-histone deacetylase (HDAC1/Rpd3) complex (HDAC). Appears to be a non-essential subunit of this complex which is not required for cell cycle regulation of progression through the G2 phase of the cell cycle. Component of the class 1 Sin3A-histone deacetylase (HDAC1/Rpd3) complex (HDAC). Not essential for stability of the complex, recruitment of the complex to some promoters, or the deacetylase activity of the complex. Does not cause cell morphology changes, cell growth defects, cell cycle phenotypes, or loss of Smr/SMRTER protein from the Sin3A-histone deacetylase (HDAC1/Rpd3) complex. Belongs to the SAP30 family.