Identification and nucleosome positioning of BdHTA9 in Brachypodium. (a) An unrooted maximum-likelihood phylogenetic tree of HTA proteins in Brachypodium, Arabidopsis, humans and yeast, constructed using MEGA5 with 100 bootstrap replicates, summarizes the evolutionary relationship among the HTA proteins and the separation in four phylogenetic subfamilies. Branches are drawn to scale with scale bar representing the number of substitutions per site. (b) Reverse-transcriptase PCR analysis of BdHTA1, BdHTA9 and BdHTA11 from leaf, apex and endosperm tissue of Bd21. Two biological replicates are shown. (c,d)ChIP analysis of HTA9:3XFLAG (H2A.Z) at 17°C shows H2A.Z is enriched at the -1 and +1 nucleosomes of HSF23 (c) and HSP70 (d). The x-axis indicates the central position of each amplicon relative to the TSS. In each schematic, the promoter (solid line), 5'UTR (white box), exons (black box) and TSS (arrow) are shown. Mock reactions (grey) were performed on identical tissue from wild-type plants. Values are the mean ± standard error of three biological replicates.
Boden et al. Genome Biology 2013 14:R65 doi:10.1186/gb-2013-14-6-r65