在T-均菌体中的内部移动性:由内部开放的读取框架促进的I组内部的高频继承
S M Quirk1, D Bell-Pedersen, M Belfort
1Wadsworth Center for Laboratories and Research, New York State Department of Health, Albany 12201-0509.
Cell
|February 10, 1989
概括
即使T菌体内基因可以在基因之间移动,将内基因减数转换为内基因加值版本. 这种移动性取决于内部基因表达和DNA重组,解释了菌体中的内部分布.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 微生物学 微生物学
背景情况:
- T-偶菌体在保存的基因内拥有内基.
- 这些内子的移动性和分布模式仍然不完全理解.
研究的目的:
- 为了研究T偶菌体内内部移动的机制.
- 阐明了内部插入和继承的分子基础.
主要方法:
- 研究了T偶基因 (td,sunY,nrdB) 中的内子转化.
- 评估了内部开放式读取框架 (ORF) 表达在转换中的作用.
- 通过RNA独立的基于DNA的重组分析了内部插入.
- 研究了外因子同质性和整合部位序列对遗传的影响.
主要成果:
- 已经证明了Td和sunY的intron-minus转化为intron-plus等位基因的高效,非互惠的转化,但不是nrdB.
- 转换所需的表达是特定的内子ORF.
- 内子插入是通过被外子同质性刺激的重复性重组发生的.
- 整合部位的td内置ORF产品的裂变对于遗传至关重要;删除取消了这一点.
结论:
- 提供了一个新型的基因转化在核细胞的例子.
- 提出了一种用于内部移动性和它们在保存的菌体基因中的分布的分子机制.
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