在花粉中的可转移元素的表观遗传重编程和小RNA沉默
R Keith Slotkin1, Matthew Vaughn, Filipe Borges
1Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA.
Cell
|February 11, 2009
概括
阿拉比多普西斯花粉中的可转移元素 (TEs) 在植物核中被重新激活,而不是精子细胞. 从这些TE产生的小干扰RNAs (siRNAs) 可能调节它们在配体中的沉默.
科学领域:
- 植物分子生物学 植物分子生物学
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 基因组学就是基因组学.
背景情况:
- 可转移元素 (TE) 构成突变致病风险,但通常由表观遗传机制和小干扰RNA (siRNA) 抑制.
- 这种沉默在配子中至关重要,以防止可能有害的TE插入的传播给后代.
研究的目的:
- 为了研究植物体内TEs的活性和调节,特别是在Arabidopsis花粉中.
- 了解花粉植物核在TE动态和潜在的表观遗传重编程中的作用.
主要方法:
- 在Arabidopsis花粉中分析TE表达和转移.
- 与TE相关的小干扰RNAs (siRNAs) 的量化.
- 检查表观遗传修饰,包括DNA甲基化和异色染色素重塑.
主要成果:
- TEs意外地在花粉植物核中重新激活和转移,花粉植物核是一个不为胚胎贡献DNA的细胞.
- TE的重新激活与异性染色体重塑剂"DNA甲基化1的减少"和减少的TE siRNAs的下调相关.
- 来自Athila逆转移体的21核酸siRNAs在花粉和精子细胞中产生和积累.
结论:
- TEs可以在雄性体内某个特定的伴侣细胞 (植物核) 中被重新激活.
- 配子中积累的siRNAs表明了针对TE沉默的机制,可能源自重新激活的TE.
- 转基因伴侣细胞中的重编程可能是调节跨物种体内雌激素活性的一种保存机制.
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