Expression And Function Analysis Of HDA909 Gene From Populus Alba × Populus Gllandulosa

Chromatin is the carrier of genetic material in eukaryotic,and histones are important components of chromatin.Post-translational modifications of hisones playa vital regulatory role in gene expression.Of the histone modifications,histone acetylation is studied earlier and more clearly.The process of histone acetylation is mainly regulated by two enzymes,one is histone acetyltransferase(HAT)and the other is histone deacetylase(HDAC).In recent years,some studies have shown that histone deacetylase(HDACs)play a very important role in the growth and development of plants and in response to stresses.In this study,the histone deacetylase gene HDA909 was cloned from Populus alba× Populus gllandulosa leaves,and the coding region of the gene is 1323 bp.The amino acid sequence of the HDA909 genewas analyzed with bioinformatics tools;subcellular localization of the protein encoded by HDA909 gene was determined;tthe expression of the HDA909 genein different organs and in response to salt,drought stresses were analyzed by real-time PCR.The HDA909 gene was cloned into pROK?vector and transformed into Agrobacterium tumefaciens.of the HDA909 gene was introduced into Arabidopsis thaliana and Populus alba×Populus gllandulosa by means of soaking and Agrobacterium mediated transformation.Bioinformatics analysis showed that the amino acid residues of HDA909 protein was 440.The isoelectric point was 5.26,and the hydrophobic was-0.434,indicating that it is a hydrophilic protein.The HDA909 and its homologous proteins from the other plant specieshave conserved sequences.The HDA909 from 84 K poplar is closely related to HDA909 from Populus trichocarpa in evolution.Subcellular localization analysis showed that the HDA909 was located in the cytoplasm.Real-time PCR showed that the HDA909 was expressed in root,stem and leaf,and its expressionwas regulated by drought and salt stresses.The transgenic plants were analyzed and the data showed that the the expression of HDA909 gene in Arabidopsis can promote lateral root growth of Arabidopsis,and enhanced the tolerance of transgenic plants to drought and salt stresses.In addition,the over-expression of HDA909 in 84 K poplar promoted the growth of lateral roots.