Expression And Faction Of HDT901 Gene From Populus Trichocarpa

There are many types of post-translational modifications of histones,including acetylation,methylation,phosphorylation,ubiquitination,and ADP ribosylation.Histone acetylation is an important epigenetic modification and plays an important role in the regulation of chromatin structure and remodeling,gene expression,and environmental stress responses.Histone acetylation levels are reversibly regulated by histone acetyltransferase(HAT)and histone deacetylase(HDAC).HDAC plays an important regulatory role in plant growth,development and stress responses.At present,the function of HDAC in woody plants is less known.In this study,a gene encoding an HD2-type histone deacetylase,HDT901,was cloned from Populus trichocarpa,and its sequence,expression and function was investigated.The full length of the coding region of the HDT901 gene was 828 bp,encoding a protein with 275 amino acids.The protein sequence of HDT901 was fully analyzed using bioinformatics tools.The HDT901 protein has a typical zinc finger domain.It has a high amino acid sequence identity with HDT1 from cassava.Phylogenetic analysis showed that HDT901 has a close relationship in evolution with HDT1 from cassava as well.The promoter region of the HDT901 gene contains multiple cis-acting elements such as light response element,gibberellin response element,auxin response element,salicylic acid response element,and low temperature response element.The sub-cellular localization analysis showed that HDT901 was localized in nucleus.The real-time PCR results showed that the expression of HDT901 in leaf,stem and root was inhibited by salt stress.In order to know the function of HDT901 in environmental stress responses,the HDT901 over-expression vector was constructed and the HDT901 gene was introduced into Arabidopsis and 84K poplar.The expression of HDT901 in Arabidopsis improved the growth of transgenic roots,but decreased the tolerance of transgenic seedlings to salt and drought stresses.Meanwhile,the expression of HDT901 in 84K poplar decreased the salt and drought tolerance of transgenic poplar plants.These findings indicated that the HDT901 gene plays an important role in salt and drought stress responses.