NtSET1, a member of a newly identified subgroup of plant SET-domain-containing proteins, is chromatin-associated and its ectopic overexpression inhibits tobacco plant growth.
NtSET1, a member of a newly identified subgroup of plant SET-domain-containing proteins, is chromatin-associated and its ectopic overexpression inhibits tobacco plant growth.
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DOI：
10.1046/j.1365-313x.2001.01135.x
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发表时间：
2002-01
期刊：
影响因子：
--
通讯作者：
Wen-Hui Shen
中科院分区：
文献类型：
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作者：
Wen-Hui Shen
SET结构域和染色质结构域被认为是蛋白质的标志性基序，通过影响染色质结构的区域组织来促进基因表达的表观遗传控制。本文报道了在烟草和拟南芥中鉴定出的一个新的含SET结构域的蛋白亚组，该亚组与果蝇位置效应杂色阻遏蛋白SU（VAR）3-9和酵母着丝粒沉默蛋白CLR 4具有最高的同源性。烟草SET结构域的蛋白质（NtSET 1）融合到绿色荧光蛋白（GFP），作为一个视觉标记的重组蛋白在活细胞中的定位。而对照GFP蛋白单独均匀地分散在细胞核和细胞质内，NtSET 1-GFP融合蛋白显示出不均匀的定位到间期烟草TBY 2细胞的多个核区域。在有丝分裂过程中，NtSET 1-GFP与非随机分布的浓缩染色体相关联。因此，NtSET 1似乎在植物染色质中具有不同的靶区域。NtSET 1-GFP在转基因烟草中的过表达抑制了植物的生长，暗示NtSET 1可能通过形成高阶染色质结构域参与了生长控制基因的转录抑制。
The SET- and chromo-domains are recognized as signature motifs for proteins that contribute to epigenetic control of gene expression through effects on the regional organization of chromatin structure. This paper reports the identification of a novel subgroup of SET-domain-containing proteins in tobacco and Arabidopsis, which show highest homologies with the Drosophila position-effect-variegation repressor protein SU(VAR)3-9 and the yeast centromer silencing protein CLR4. The tobacco SET-domain-containing protein (NtSET1) was fused to the green fluorescence protein (GFP) that serves as a visual marker for localization of the recombinant protein in living cells. Whereas control GFP protein alone was uniformly dispersed within the nucleus and cytoplasm, the NtSET1-GFP fusion protein showed a non-uniform localization to multiple nuclear regions in interphase tobacco TBY2 cells. During mitosis, the NtSET1-GFP associated with condensed chromosomes with a non-random distribution. The NtSET1 thus appears to have distinct target regions in the plant chromatin. Overexpression of the NtSET1-GFP in transgenic tobacco inhibited plant growth, implicating the possible involvement of the NtSET1 in transcriptional repression of growth control genes through the formation of higher-order chromatin domains.