Histones play a critical role in transcriptional regulation, cell cycle progression, and developmental events. Histone acetylation/deacetylation alters chromosome structure and affects transcription factor access to DNA. The protein encoded by HDAC5 belongs to the class II histone deacetylase/acuc/apha family. It possesses histone deacetylase activity and represses transcription when tethered to a promoter. It coimmunoprecipitates only with HDAC3 family member and might form multicomplex proteins. It also interacts with myocyte enhancer factor-2 (MEF2) proteins, resulting in repression of MEF2-dependent genes. This gene is thought to be associated with colon cancer. Two transcript variants encoding different isoforms have been found for this gene. An important paralog of this gene is HDAC4. HDAC9 (Histone Deacetylase 9) is a Protein Coding gene. Diseases associated with HDAC9 include Gastrointestinal Neuroendocrine Tumor and Cutaneous T Cell Lymphoma. Among its related pathways are PEDF Induced Signaling and Phospholipase-C Pathway. GO annotations related to this gene include transcription factor binding and histone deacetylase binding. An important paralog of this gene is HDAC5.