title: AtHD2D Gene Plays a Role in Plant Growth, Development, and Response to Abiotic Stresses in Arabidopsis thaliana.
abstract: The histone deacetylases play important roles in the regulation of gene expression and the subsequent control of a number of important biological processes, including those involved in the response to environmental stress. A specific group of histone deacetylase genes, HD2, is present in plants. In Arabidopsis, HD2s include HD2A, HD2B, HD2C, and HD2D. Previous research showed that HD2A, HD2B, and HD2C are more related in terms of expression and function, but not HD2D. In this report, we studied different aspects of AtHD2D in Arabidopsis with respect to plant response to drought and other abiotic stresses. Bioinformatics analysis indicates that HD2D is distantly related to other HD2 genes. Transient expression in Nicotiana benthamiana and stable expression in Arabidopsis of AtHD2D fused with gfp showed that AtHD2D was expressed in the nucleus. Overexpression of AtHD2D resulted in developmental changes including fewer main roots, more lateral roots, and a higher root:shoot ratio. Seed germination and plant flowering time were delayed in transgenic plants expressing AtHD2D, but these plants exhibited higher degrees of tolerance to abiotic stresses, including drought, salt, and cold stresses. Physiological studies indicated that the malondialdehyde (MDA) content was high in wild-type plants but in plants overexpressing HD2D the MDA level increased slowly in response to stress conditions of drought, cold, and salt stress. Furthermore, electrolyte leakage in leaf cells of wild type plants increased but remained stable in transgenic plants. Our results indicate that AtHD2D is unique among HD2 genes and it plays a role in plant growth and development regulation and these changes can modulate plant stress responses.
authors.affiliation: College of Life Science, Northwest A & F University Yangling, China.
authors.forename: Zhaofen
authors.initials: Z
authors.lastname: Han
authors.affiliation: Department of E-A Information Engineering, Liaoning Institute of Science and Technology Benxi, China.
authors.forename: Huimin
authors.initials: H
authors.lastname: Yu
authors.affiliation: College of Forestry, Northwest A & F University Yangling, China.
authors.forename: Zhong
authors.initials: Z
authors.lastname: Zhao
authors.affiliation: Southern Crop Protection and Food Research Centre, Agriculture and Agri-food Canada London, ON, Canada.
authors.forename: David
authors.initials: D
authors.lastname: Hunter
authors.affiliation: College of Life Science, Northwest A & F University Yangling, China.
authors.forename: Xinjuan
authors.initials: X
authors.lastname: Luo
authors.affiliation: Key Laboratory of South China Agricultural Plant Genetics and Breeding, South China Botanical Garden, Chinese Academy of Sciences Guangzhou, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Duan
authors.affiliation: Southern Crop Protection and Food Research Centre, Agriculture and Agri-food Canada London, ON, Canada.
authors.forename: Lining
authors.initials: L
authors.lastname: Tian
keywords: AtHD2D; expression and function; plant development; protein sub-cellular localization; stress tolerance