Cloning and expression analysis of PtHDT903, a HD2-type histone deacetylase gene in Populus trichocarpa

Histone deacetylases (HDACs) catalyse the deacetylation of core histones and non-histone proteins. Histone deacetylases work in concert with histone acetyltransferases to modify the structure and function of chromatins, and regulate gene transcription. Histone deacetylases are critical enzymes involved in the regulation of multiple cellular processes, such as plant growth and development, stress responses and gene silencing. Plant HDACs are a supergene family and can be divided into three families, namely RPD3/HDA1, HD2 and SIR2. HD2 specifically occur in plants, not in fungi and animals. In this study, an HD2-type HDAC gene, PtHDT903, was cloned from Populus trichocarpa. Its amino acid sequence, subcellular localization and expression patterns under abiotic stresses were analysed. The results showed that PtHDT903 encodes a hydrophilic and acidic protein consisting of 305 amino acids. The predicted PtHDT903 protein has the conserved domains which found in the other HD2-type HDACs. The PtHDT903 protein was localized in the nucleus. The expression of the PtHDT903 gene was down-regulated by salt stress, whereas it was up-regulated by cold. The results provide valuable information for the further functional study of PtHDT903