THREE DIMENSIONAL CHARACTERIZATION OF HIGHLY ACETYLATED REGIONS IN BARLEY NUCLEI.

¹ Hokuriku National Agricultural Experiment Station, Joetsu 943-0193, Japan

² Science University of Tokyo, Shinjuku-ku 162-8601, Japan

³ Faculty of Horticulture, Chiba University, Mastudo 271-8510, Japan

⁴ Joetsu University of education, Joetsu 943-8512, Japan

⁵ Anatomy Department, University of Birmingham Medical School, Birminghaaam B15 2TT, UK

⁶ Faculty of Engineering, Graduate School of Osaka University, Suita 565-0871, Japan

Histone H4, one of the structural proteins of nucleosome core is acetylated in the lysine residues at the N-terminal domain according to the certain chromosomal status. The analysis of topological distribution of acetylated area using a three dimensional microscopy (3D-analysis) was already established in our laboratory using non-fixed barley nuclei. There were some hyper-acetylated regions (HARs) clustered close to the surface sphere of nucleus. In this study, the HARs were characterized using an indirect-immunostaining method and fluorescence in situ hybridization. As a result, co-localization of the HARs and signals from centromeric probe were detected. Each signal of the acetylated regions contains two brighter dots that indicate more acetylated regions, and was overlapped centromeric signals. Our results indicate that the centromeric regions were acetylated very highly, and this suggests that potential for transcriptional activity near the centromeric regions or some other functional activity.