The EpiQuik™ HDAC5 Assay Kit （Colorimetric） is a complete set of optimized buffers and reagents to colorimetrically measure the total amount of HDAC5 proteins quantitatively, through an ELISA-like method, from fresh tissue and cultured cells of human and mouse without the need for electrophoresis and transfer processes.

• Very fast procedure, which can be finished within 4 hours.
• Innovative colorimetric assay to quantitatively measure HDAC5 protein amount without the need for electrophoresis.
• High sensitivity and specificity -- HDAC5-specific detection with a detection limit as low as 0.5 ng of HDAC5 protein.
• Strip microplate format makes the assay flexible: manual or high throughput analysis.
• HDAC5 control is included, which allows for the HDAC5 protein amount of the sample to be properly quantified.
• Simple, reliable, and consistent assay conditions.

Background Information
Histone deacetylases （HDACs） play a critical role in transcriptional repression of gene expression in eukaryotic cells by catalyzing the hydrolytic removal of acetyl groups from histone lysine residues. HDACs are tightly involved in cell cycle regulation, cell proliferation, and the development of human cancer. HDAC inhibition displays significant effects on apoptosis, cell cycle arrest, and differentiation in cancer cells. HDAC inhibitors are currently being developed as potential anti-cancer agents. Three distinct families of HDACs have been described, comprising a group of at least 20 proteins in humans. HDAC5 is a class II histone deacetylase containing 1122 amino acid residues. HDAC5 possesses histone deacetylase activity and represses transcription when tethered to a promoter. HDAC5 seems to interact in a multiprotein complex with HDAC3 family members. Also, through interaction with many transcription factors, HDAC5 regulates many biological processes including cell cycle progression.

Principle & Procedure
In an assay with this kit, the unique HDAC affinity substrate is stably coated on the strip well. The sample is added into the well and HDAC5 proteins contained in the sample bind to the substrate. The bound HDAC5 can be recognized with an HDAC5-specific antibody and colorimetrically quantified through an ELISA-like reaction. After reading the optical density on a microplate spectrophotometer at a wavelength of 450 nm, the amount of HDAC5 will be proportional to the intensity of the color development.

Fig. 1. Schematic procedure of the EpiQuik™ HDAC5 Assay Kit （Colorimetric）.

Fig. 2. Illustrated standard curve generated with HDAC5 control.