The HeLa nuclear extract is unpurified and therefore contains possibly all enzymes that can be found in the nucleus of this cell line. The most abundant HDACs in the HeLa nuclear extract are the class I HDACs with HDAC1, HDAC2 and HDAC3 being the most predominant. Other HDACs are present in lower amounts, but the extract has not been fully profiled so we cannot provide information on exactly which ones are present or their respective amount/ratio.