Supplementary Material for: Distribution patterns of phosphorylated Thr 3 and Thr 32 of histone H3 in plant mitosis and meiosis

Cell cycle dependent phosphorylation of conserved N-terminal tail residues of histone H3 has been described in both animal and plant cells. Through cytogenetic approaches using different plant species we show a detailed description of distribution patterns of phosphorylated histone H3 at either threonine 3 or threonine 32 in mitosis and meiosis. In meristematic cells of the large genome species <i>Secale cereale, Vicia faba </i>and <i>Hordeum vulgare </i>we have found that phosphorylation of both threonine residues begins in prophase, and dephosphorylation occurs in late anaphase. However, in the small genome species <i>Arabidopsis thaliana </i>dephosphorylation occurs at anaphase. In the first division of meiosis of species with large genomes phosphorylation of histone H3 at either threonine 3 or threonine 32 is seen first in diakinesis and extends to anaphase I, whereas in the second division these post-translational modifications are visible at metaphase II through anaphase II. While in <i>A. thaliana </i>dephosphorylation takes place at anaphase I and II. In all species analysed phosphorylated H3 at either threonine 3 or threonine 32 are distributed along the entire length of chromosomes during mitotic metaphase and metaphase I. In the second meiotic division threonine 3 phosphorylation is restricted to the pericentromeric domain, while phosphorylation of threonine 32 is widespread along chromosome arms of all species analysed.