The Arabidopsis SDG4 contributes to the regulation of pollen tube growth by methylation of histone H3 lysines 4 and 36 in mature pollen.
Plant SET domain proteins are known to be involved in the epigenetic control of gene expression during plant development. Here, we report that the Arabidopsis SET domain protein, SDG4, contributes to the epigenetic regulation of pollen tube growth, thus affecting fertilization. Using an SDG4-GFP fusion construct, the chromosomal localization of SDG4 was established in tobacco BY-2 cells. In Arabidopsis, sdg4 knockout showed reproductive defects. Tissue-specific expression analyses indicated that SDG4 is the major ASH1-related gene expressed in the pollen. Immunological analyses demonstrated that SDG4 was involved in the methylation of histone H3 in the inflorescence and pollen grains. The significant reduction in the amount of methylated histone H3 K4 and K36 in sdg4 pollen vegetative nuclei resulted in suppression of pollen tube growth. Our results indicate that SDG4 is capable of modulating the expression of genes that function in the growth of pollen tube by methylation of specific lysine residues of the histone H3 in the vegetative nuclei.
Cartagena
Joyce A
JA
Department of Biotechnology, Graduate School of Engineering, Osaka University 2-1 Yamadaoka, Suita 565-0871, Osaka, Japan.
Matsunaga
Sachihiro
S
Seki
Motoaki
M
Kurihara
Daisuke
D
Yokoyama
Masami
M
Shinozaki
Kazuo
K
Fujimoto
Satoru
S
Azumi
Yoshitaka
Y
Uchiyama
Susumu
S
Fukui
Kiichi
K
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D002460:Cell Line; D017931:DNA Primers / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D017343:Genes, Plant; D011495:Histone-Lysine N-Methyltransferase / Q000235:genetics / Q000378:metabolism; D006657:Histones / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008239:Lysine / Q000737:chemistry / Q000378:metabolism; D008745:Methylation; D008969:Molecular Sequence Data; D009154:Mutation; D020411:Oligonucleotide Array Sequence Analysis; D030821:Plants, Genetically Modified; D011058:Pollen / Q000235:genetics / Q000378:metabolism; D053205:Pollen Tube / Q000254:growth & development* / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D014026:Nicotiana
D029681:Arabidopsis Proteins; D017931:DNA Primers; D018744:DNA, Plant; D006657:Histones; D011495:Histone-Lysine N-Methyltransferase; D008239:Lysine