Analysis of molecular basis between heterochromatin and euchromatin in plant cells

植物细胞异染色质和常染色质的分子基础分析

基本信息

批准号：
18570061
负责人：
TANAKA Ichiro
金额：
$ 2.57万
依托单位：
Yokohama City University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2006
资助国家：
日本
起止时间：
2006 至 2007
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-18570061/
关键词：
Vegetative nucleus Pollen Chromatin Antibody Modification Lilium longiflorum Histone Generative nucleus テッポウュリ

项目摘要

Eukaryotic chromatin is microscopically classified into heterochromatin and euchromatin. Although specific proteins such as HP1 (heterochromatin protein 1) give rise to heterochromatin in animal cells, the factors relating to different chromatin states in plant cells remain unclear. So, in this study, we tried to clarify the major factor to determine the chromatin differentiation between heterochromatin and euchromatin in the case of pollen. Because, the generative nucleus within pollen has highly condensed chromatin (heterochromatin), whereas the vegetative nucleus contains diffuse chromatin (euchromatin).As a result, it was demonstrated that gHl, which had been identified as male gametic nucleus-highly concentrated histone H1, showed a remarkable polarization just after the first microspore mitosis. Namely, gHl was only detected in the generative nucleus and largely accumulated in the male gametic nucleus during pollen development. On the other hand, gH1 was barely detected in the vegetative nucleus. Next, two histone H1 genes, gH1 and somatic type-histone H1 (sH1), were isolated and expression analysis was done by RT-PCR method. As a result, while the expression of sH1 came to a stop during pollen maturation, the expression of gH1 remarkably increased from just before the first microspore mitosis. Accordingly, gH1 was assumed as a factor of heterochromatization. The function of gH1 is now investigating by gene transfer into somatic cells with GFP.

真核生物染色质在显微镜下分为异染色质和常染色质。尽管HP1（异染色质蛋白1）等特定蛋白质在动物细胞中产生异染色质，但与植物细胞中不同染色质状态相关的因素仍不清楚。因此，在本研究中，我们试图阐明花粉中决定异染色质和常染色质染色质分化的主要因素。因为，花粉内的生殖核具有高度浓缩的染色质（异染色质），而营养核含有弥散的染色质（常染色质）。因此，证明了gHl（已被鉴定为雄性配子核-高度浓缩的组蛋白H1），在第一次小孢子有丝分裂后立即表现出显着的极化。即，gH1仅在生殖核中检测到，并且在花粉发育期间大量积累在雄配子核中。另一方面，在营养细胞核中几乎检测不到 gH1。接下来，分离了两个组蛋白H1基因gH1和体细胞型组蛋白H1（sH1），并通过RT-PCR方法进行表达分析。结果，虽然sH1的表达在花粉成熟期间停止，但gH1的表达从第一次小孢子有丝分裂之前显着增加。因此，gH1 被假定为异染色质化的一个因素。目前正在通过 GFP 将基因转移至体细胞来研究 gH1 的功能。