Different Types of Maize Histone Deacetylases Are Distinguished by a Highly Complex Substrate and Site Specificity

Abstract

Enzymes involved in histone acetylation have been identified as important transcriptional regulators. Maize embryos contain three histone deacetylase families: RPD3-type deacetylases (HD1-B), nucleolar phosphoproteins of the HD2 family, and a third form unrelated to RPD3 and HD2 (HD1-A). Here we first report on the specificity of deacetylases for core histones, acetylated histone H4 subspecies, and acetylated H4-lysine residues. HD1-A, HD1-B, and HD2 deacetylate all four core histones, although with different specificity. However, experiments with histones from different sources (hyperacetylated MELC and chicken histones) using antibodies specific for individually acetylated H4-lysine sites indicate that the enzymes recognize highly distinct acetylation patterns. Only RPD3-type deacetylase HD1-B is able to deacetylate the specific H4 di-acetylation pattern (position 12 and 5) introduced by the purified cytoplasmic histone acetyltransferase B after incubation with pure nonacetylated H4 subspecies. HD1-A and HD2 exist as phosphorylated forms. Dephosphorylation has dramatic, but opposite effects; whereas HD2 loses enzymatic activity upon dephosphorylation, HD1-A is activated with a change of specificity against acetylated H4 subspecies. The data suggest that different types of deacetylases interact with different and highly specific acetylation patterns on nucleosomes.

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

“…This indicates that AtHDA7 is required for embryogenesis. Studies concerning the relationships between histone deacetylation/acetylation and embryogenesis have been reported in Arabidopsis (Long et al, 2006) as well as in maize (Zea mays), where HATs and HDACs were first isolated in embryos (Kölle et al, 1999). Varotto and colleagues (2003) showed that ZmHDA108, the closest homolog to AtHDA7, is particularly abundant in kernels at 3 to 8 d after pollination and in embryos.…”

Regulation and Processing of Maize Histone Deacetylase Hda1 by Limited Proteolysis

“…The arrow marks the position of the high molecular weight ZmHda1 form, and the asterisk marks the position of the cleaved C-terminal peptide. comitant change of substrate specificity, in particular toward acetylated H4 isoforms (Kölle et al, 1999). In agreement with this interpretation is the fact that native ZmHda1-p48 always exists as a mixture of phosphorylated and dephosphorylated enzyme forms (Brosch et al, 1996;A.…”

“…When chromatographic fractions were concentrated Ͼ 10-fold, two proteins (45 and 48 kD) became detectable that coeluted exactly with the enzyme activity ( Figure 3C), suggesting that the 84-and 65-kD proteins may represent inactive pre-forms of ZmHda1-p48. The 45-and 48-kD protein bands comigrated with the phosphorylated and unphosphorylated forms of purified ZmHda1-p48 (Brosch et al, 1996;Kölle et al, 1999;G. Brosch and A. Loidl, unpublished results).…”

“…Loidl and G. Brosch, unpublished data). It should be mentioned in this context that dephosphorylation of the nucleolar maize HD2 resulted in a complete loss of enzymatic activity (Kölle et al, 1999). The regulatory role of the post-translational phosphorylation of histone deacetylases in controlling both enzymatic activity and the ability to interact with other proteins was reported recently in animal cell systems (Bertos et al, 2001;Pflum et al, 2001;Tsai and Seto, 2002;Zhang et al, 2002).…”

“…It can be purified by chromatography from maize extracts as a 48-kD protein that is subject to phosphorylation (Brosch et al, 1992(Brosch et al, , 1996. In vitro dephosphorylation of the purified enzyme is accompanied by a significant increase of histone deacetylase activity and altered substrate specificity with respect to differentially acetylated isoforms of histone H4 (Kölle et al, 1999).…”