Structure and expression of the rice class-I type histone deacetylase genes OsHDAC1-3: OsHDAC1 overexpression in transgenic plants leads to increased growth rate and altered architecture.
Histone deacetylases (HDACs) modulate chromatin structure and transcription. HDACs have been studied as negative regulators in eukaryotic transcription. We isolated the rice OsHDAC1-3 genes for class I-type histone deacetylases, which are related to the RPD3 family. The OsHDAC1 gene encoded a protein of approximately 57 kDa that shared 73.5, 72.7, 79.9, and 57.1% amino acid sequence identity with the OsHDAC2, OsHDAC3, maize RPD3, and human HDAC1 proteins, respectively. Genomic structures and Southern blot analyses revealed that OsHDAC1-3 contained seven, six, and seven exons, respectively, and constituted a class I-type family in the rice genome. OsHDAC1 was expressed at similar levels in the leaves, roots, and callus cells, whereas OsHDAC2 and 3 were expressed in the roots and callus cells, but not in the leaves, exhibiting distinct tissue specificity. To explore the role of histone deacetylases in transgenic plants, we inserted the OsHDAC1 cDNA fragment into the expression vector Ai::OsHDAC1 under the control of the ABA-inducible promoter Ai, and transformed the construct into rice. Levels of mRNA, protein, and HDAC activity were significantly increased in Ai::OsHDAC1 callus cells. The amount of tetra-acetylated H4 in the transgenic cells was greatly reduced, and the reduction was abolished upon treatment with trichostatin A. These results demonstrate that OsHDAC1 overexpression in transgenic cells both yields enzymatically active HDAC complexes and induces changes in histone acetylation in vivo. The overexpression leads to a range of novel phenotypes, involving increased growth rate and altered plant architecture, suggesting that OsHDAC1 functions in the genome-wide programming of gene expression.
Jang
In-Cheol
IC
Department of Biological Science, Myongji University, Yongin 449-728, Korea.
Pahk
Yoon-Mok
YM
Song
Sang Ik
SI
Kwon
Ho Jeong
HJ
Nahm
Baek Hie
BH
Kim
Ju-Kon
JK
D000040:Abscisic Acid / Q000494:pharmacology; D000595:Amino Acid Sequence; D046508:Culture Techniques; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D006655:Histone Deacetylases / Q000235:genetics* / Q000378:metabolism; D006657:Histones / Q000187:drug effects / Q000378:metabolism; D006877:Hydroxamic Acids / Q000494:pharmacology; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D012275:Oryza / Q000235:genetics* / Q000254:growth & development; D010641:Phenotype; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D012333:RNA, Messenger / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
D018076:DNA, Complementary; D006657:Histones; D006877:Hydroxamic Acids; D007527:Isoenzymes; D010940:Plant Proteins; D012333:RNA, Messenger; C012589:trichostatin A; D000040:Abscisic Acid; D006655:Histone Deacetylases