摘要
Arabidopsis thaliana histone deacetylase 1 （AtHD1 or AtHDA19）, a homolog ot yeast RPD3, is a global regulator ot many physiological and developmental processes in plants. In spite of the genetic evidence for a role of AtHD1 in plant gene regulation and development, the biochemical and cellular properties ofAtHD 1 are poorly understood. Here we report cellular localization patterns ofAtHD 1 in vivo and histone deacetylase activity in vitro. The transient and stable expression of a green fluorescent protein （GFP）-tagged AtHD1 in onion cells and in roots, seeds and leaves of the transgenic Arabidopsis, respectively, revealed that AtHD1 is localized in the nucleus presumably in the euchromatic regions and excluded from the nucleolus. The localization patterns ofAtHD 1 are different from those of AtHD2 and AtHDA6 that are involved in nucleolus formation and silencing of transgenes and repeated DNA elements, respectively. In addition, a histone deacetylase activity assay showed that the recombinant AtHD 1 produced in bacteria demonstrated a specific histone deacetylase activity in vitro. The data suggest that AtHD 1 is a nuclear protein and possesses histone deacetylase activities responsible for global transcriptional regulation important to plant growth and development.
基金
We thank Mary Bryk and Timothy Hall for critical suggestions to improve the manuscript,David Stelly and Keerti Rathore for assistance in GFP localization studies in onion cells,and Stanislav Vitha in the Microscopy and Imaging Center at Texas A&M University for technical support for epifluorescence microscopic image analysis in the transgenic plants.The work is supported by grants from the National Institutes of Health(GM067015)
the National Science Foundation Plant Genome Research Program(DBI0077774)to Z J C.
