由三体促进的bxd非编码RNA的转录通过转录干扰抑制cis中的Ubx
Svetlana Petruk1, Yurii Sedkov, Kristen M Riley
1Department of Biochemistry, Thomas Jefferson University, Philadelphia, PA 19107, USA.
Cell
|December 19, 2006
概括
从bithoraxoid (bxd) 区域转录的长非编码RNA (ncRNA) 令人惊的是抑制了Ultrabithorax (Ubx) 基因表达. 这种抑制通过cis中的ncRNA转录发生,由Trithorax复合体TAC1.介导.
科学领域:
- 发育生物学 发展生物学
- 基因法规 基因法规
- 非编码RNA生物学
背景情况:
- 长非编码RNAs (ncRNAs) 从基因组的大部分部分转录.
- 之前,人们曾认为比索拉克索 (bxd) ncRNAs通过招募三组 (trxG) 蛋白来激活Ultrabithorax (Ubx) 表达.
- bxd ncRNAs在调节Ubx表达中的确切作用尚不清楚.
研究的目的:
- 研究bxdncRNAs在调节Ubx表达中的作用.
- 阐明bxd ncRNAs影响ubx转录的机制.
- 为了了解bxdncRNAs,Ubx和Trithorax复合体之间的相互作用.
主要方法:
- 对Drosophila胚胎和影像盘中Ubx和bxdncRNAs的非重叠表达模式的分析.
- 排除小干扰RNA (siRNA) 或微RNA (miRNA) 中介抑制的研究.
- 对Trithorax复合体 (TAC1) 结合模式与Ubx和bxd ncRNA表达相关的检查.
主要成果:
- Ubx和bxdncRNAs表现出非重叠的表达模式,这表明ncRNAs的抑制作用.
- 由bxdncRNAs抑制Ubx是独立于siRNA或miRNA路径的.
- 在cis中 ncRNA 转录的作用是抑制 Ubx 转录.
- 特里索拉克斯复合体 (TAC1) 结合了Ubx被表达时的Ubx编码区域和Ubx被抑制时的bxd区域.
结论:
- 与之前的假设相反,bxd ncRNAs抑制,而不是激活,Ubx表达.
- ncRNA转录本身,在cis中起作用,是Ubx抑制的机制.
- TAC1通过促进bxdncRNA延长来促进Ubx的马赛克表达模式,从而导致Ubx的转录抑制.
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