Histone modifications in Arabidopsis- high methylation of H3 lysine 9 is dispensable for constitutive heterochromatin.

TY - JOUR

T1 - Histone modifications in Arabidopsis- high methylation of H3 lysine 9 is dispensable for constitutive heterochromatin.

AU - Jasencakova, Zusana

AU - Soppe, Wim J J

AU - Meister, Armin

AU - Gernand, Dorota

AU - Turner, Bryan M

AU - Schubert, Ingo

N1 - Keywords: Arabidopsis; Arabidopsis Proteins; Cell Cycle; Cell Nucleolus; Chromosome Structures; DNA Methylation; Euchromatin; Heterochromatin; Histone-Lysine N-Methyltransferase; Histones; Lysine; Methyltransferases; Mutation; Plant Roots

PY - 2003

Y1 - 2003

N2 - N-terminal modifications of nucleosomal core histones are involved in gene regulation, DNA repair and recombination as well as in chromatin modeling. The degree of individual histone modifications may vary between specific chromatin domains and throughout the cell cycle. We have studied the nuclear patterns of histone H3 and H4 acetylation and of H3 methylation in Arabidopsis. A replication-linked increase of acetylation only occurred at H4 lysine 16 (not for lysines 5 and 12) and at H3 lysine 18. The last was not observed in other plants. Strong methylation at H3 lysine 4 was restricted to euchromatin, while strong methylation at H3 lysine 9 occurred preferentially in heterochromatic chromocenters of Arabidopsis nuclei. Chromocenter appearance, DNA methylation and histone modification patterns were similar in nuclei of wild-type and kryptonite mutant (which lacks H3 lysine 9-specific histone methyltransferase), except that methylation at H3 lysine 9 in heterochromatic chromocenters was reduced to the same low level as in euchromatin. Thus, a high level of H3methylK9 is apparently not necessary to maintain chromocenter structure and does not prevent methylation of H3 lysine 4 within Arabidopsis chromocenters.

AB - N-terminal modifications of nucleosomal core histones are involved in gene regulation, DNA repair and recombination as well as in chromatin modeling. The degree of individual histone modifications may vary between specific chromatin domains and throughout the cell cycle. We have studied the nuclear patterns of histone H3 and H4 acetylation and of H3 methylation in Arabidopsis. A replication-linked increase of acetylation only occurred at H4 lysine 16 (not for lysines 5 and 12) and at H3 lysine 18. The last was not observed in other plants. Strong methylation at H3 lysine 4 was restricted to euchromatin, while strong methylation at H3 lysine 9 occurred preferentially in heterochromatic chromocenters of Arabidopsis nuclei. Chromocenter appearance, DNA methylation and histone modification patterns were similar in nuclei of wild-type and kryptonite mutant (which lacks H3 lysine 9-specific histone methyltransferase), except that methylation at H3 lysine 9 in heterochromatic chromocenters was reduced to the same low level as in euchromatin. Thus, a high level of H3methylK9 is apparently not necessary to maintain chromocenter structure and does not prevent methylation of H3 lysine 4 within Arabidopsis chromocenters.

M3 - Journal article

C2 - 12581305

SN - 0960-7412

VL - 33

SP - 471

EP - 480

JO - Plant Journal

JF - Plant Journal

IS - 3

ER -