揭示了阿拉比多普西斯基因组 H2B.8 变体的核分布和功能背后的 cis 和 trans 调节元素
Janardan Khadka1,2, Vikas S Trishla1, Sasank Sannidhi1
1French Associates Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben Gurion, 84990, Israel.
BMC plant biology
|August 28, 2024
概括
素H2B.8,是一种独特的变异在血管精子中,控制着染色质的紧缩. 它独特的核定位和SUMOylation是其调节染色体组织的关键功能.
科学领域:
- 植物分子生物学 植物分子生物学
- 染色体生物学 染色体生物学
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
背景情况:
- 基因组是染色质的核心组成部分,它们的变体在调节基因组结构和功能方面发挥着至关重要的作用.
- 在Arabidopsis thaliana中,H2B.8基因组变体具有独特的延伸N端区域,具有保留的域,暗示了专门的功能.
- 了解核分布和基因组变异的功能影响对于破译基因调节和染色质组织至关重要.
研究的目的:
- 调查阿拉比多普西斯基因子H2B变体的核定位和功能,特别是H2B.9 (I类),H2B.5 (II类) 和H2B.8 (III类).
- 阐明H2B.8保留的N端域在其核分布和与染色质相关的功能中的作用.
- 确定H2B.8-相互作用蛋白质,并了解它们对异色染色素形成和调节的贡献.
主要方法:
- 在构成性35S促进体下,生成表达H2B.9,H2B.5和H2B.8的转基因阿拉比多普西斯植物,与绿色光蛋白 (GFP) 融合.
- 在转基因植物的各种细胞类型中微观分析H2B变异的核定位模式.
- 在原生质中进行过渡表达测试,以研究在不同的条件下,包括删除突变体和ddm1突变原生质中的H2B.8局部化.
- GFP-TRAP-合蛋白质组分析以识别H2B.8-相互作用蛋白.
主要成果:
- 在所有检查的细胞类型中,H2B.8-GFP在染色中心呈现出明显的核定位,与H2B.5-GFP和H2B.9-GFP不同,它们显示出细胞类型依赖的模式.
- 发现H2B.8-GFP会组装到核体上,其中一种异型出现SUMOylated,并且不会影响整体的核组织.
- 过渡表达揭示了H2B.8-GFP的独特的环状核外围定位,伴随着核大小的减少,这取决于N终端保留域和DDM1活动.
- 蛋白质组分析确定了H2B.8伙伴蛋白,包括H2A.W.12,这是已知的异染色素标记物.
结论:
- H2B.8 是血管精子中一种独特的组 histone 变体,参与控制染色质紧缩和聚合.
- H2B.8的N端保留域对其特定的核定位和功能至关重要.
- 和跨调节元素控制了H2B.8变体在染色体调节中的核分布和功能作用.
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