|Histone Deacetylase 4/HDAC4 in Human Testis. Histone Deacetylase 4/HDAC4 was detected in immersion fixed paraffin-embedded sections of human testis using Mouse Anti-Human Histone Deacetylase 4/HDAC4 Monoclonal Antibody (Catalog # MAB6205) at 5 µg/mL for 1 hour at room temperature followed by incubation with the Anti-Mouse IgG VisUCyte™ HRP Polymer Antibody (Catalog # VC001). Tissue was stained using DAB (brown) and counterstained with hematoxylin (blue). Specific staining was localized to cytoplasm and nuclei of sperm cells. View our protocol for IHC Staining with VisUCyte HRP Polymer Detection Reagents.|
Histone Deacetylase 4 (HDAC4; also HD4) is a founding member of the class IIa subfamily, histone deacetylase family of transcriptional regulators. Although its predicted MW is 119 kDa, it runs anomalously at 140‑150 kDa in SDS‑PAGE which may be due to extensive phosphorylation plus SUMOylation. It has an N-terminal region that interacts with transcription factors and corepressors, and a C-terminal domain that shows deacetylase activity, thus repressing gene transcription. HDAC4 is found in osteoblasts, cardiac and skeletal muscle cells, and neurons. Human HDAC4 is 1084 amino acids (aa) in length. It contains one coiled-coil region (aa 67‑177), a SUMOylation site at Lys559, a histone deacetylation domain (aa 665‑993) and one NES (aa 1051‑1084). Caspase cleavage after Asp289 generates bioactive 97 and 34 kDa fragments. There is one potential splice variant that shows an alternative start site at Met118 coupled to a five aa insertion after Thr431. Over aa 1‑68, human HDAC4 shares 96% aa identity with mouse HDAC4.