Expression and function of HD2‐type histone deacetylases in Arabidopsis development

Abstract

SummaryHD2 (histone deacetylase) proteins are plant-speci®c histone deacetylases (HDACs). The Arabidopsis genome contains four HD2 genes, namely HD2A, HD2B, HD2C, and HD2D. We have previously demonstrated that HD2A, HD2B, and HD2C can repress transcription directly by targeting to promoters in planta. Here, we show that the N-terminal conserved motif (EFWG) and histidine 25 (H25), a potential catalytic residue, were important for the gene repression activity of HD2A. In situ hybridization indicated that HD2A, HD2B, and HD2C were expressed in ovules, embryos, shoot apical meristems, and primary leaves. Furthermore, all three genes were strongly induced during the process of somatic embryogenesis. HD2D mRNA was only detected in the stems and¯owers with young siliques and may have adopted different functions. Using green¯uorescent protein (GFP) fusions, we demonstrated that HD2A, HD2B, and HD2C accumulated in the nuclei of Arabidopsis cells. Overexpression of 35S::GFP±HD2A in transgenic Arabidopsis plants generated pleiotropic developmental abnormalities, including abnormal leaves, delayed¯owering, and aborted seed development. The data showed that normal pattern of HD2 expression was essential for normal plant development and that HD2A, HD2B, and HD2C may be needed for embryogenesis and embryo development. Reverse transcriptase (RT)-PCR analysis revealed that a number of genes involved in seed development and maturation were repressed in the 35S::GFP±HD2A plants, supporting a role of HD2A in the regulation of gene expression during seed development.

Arabidopsis histone deacetylase 6: a green link to RNA silencing

“…The Arabidopsis genome encodes four members of this family, AtHDT1-4 (Pandey et al, 2002). AtHDT1 is required for reproductive development (Wu et al, 2000;Zhou et al, 2004) and, together with AtHDT2, for the establishment of leaf polarity, possibly by controlling the levels or distribution of two micro RNAs (miRNAs) involved in abaxial/adaxial axis formation (Ueno et al, 2007). AtHDT1 further controls rRNA gene dosage in Arabidopsis and modulates rRNA transcription in genetic hybrids of different Arabidopsis species, which is consistent with its nucleolar localization (Lawrence et al, 2004).…”

HISTONE DEACETYLASE19 Is Involved in Jasmonic Acid and Ethylene Signaling of Pathogen Response in Arabidopsis

“…Protoplasts were isolated from Arabidopsis seedlings as described (Zhou et al, 2004). The fluorescence photographs of protoplasts were taken using an Olympus florescent microscope (Tokyo, Japan) fitted with fluorescein isothiocyanate filters (excitation filter, 450 to 490 nm; emission filter, 520 nm; and dichroic mirror, 510 nm).…”

“…In addition, plants contain an uncommon class of HDACs, the HD2 class, which was identified in plants only (Lusser et al, 1997;Aravind and Koonin, 1998;Wu et al, 2000aWu et al, , 2003Dangl et al, 2001;Zhou et al, 2004). Studies on the mechanism of action of HDACs in plants are beginning to emerge.…”

Histone Deacetylase AtHDA7 Is Required for Female Gametophyte and Embryo Development in Arabidopsis

“…Indeed, the down-regulation of AtHDA19 induced delayed flowering, flower abnormalities, embryonic defects, and seed set reduction (Tian et al, 2003). Silencing as well as overexpression of AtHD2A severely affected seed development (Wu et al, 2000;Zhou et al, 2004). The Athda6 mutant was reported to exhibit reduced fertility to some extent (Aufsatz et al, 2002), and mutation of AtHDA9 led to an early-flowering phenotype in short-day-grown plants (Kim et al, 2013).…”