概括
鸟类莫洛尼白血病病毒 (A-MuLV) RNA包含两端同源序列,但有一个独特的中心区域. 这个独特的区域是一个插入,取代了来自父Moloney小鼠白血病病毒 (M-MuLV) 的删除序列.
科学领域:
- 分子生物学分子生物学
- 病毒学 病毒学
- 基因组学就是基因组学.
背景情况:
- 禽类莫洛尼白血病病毒 (A-MuLV) 病毒含有30S,5.6 kb的RNA.
- 这种RNA可以在无细胞系统中转化,产生特征性的A-MuLV蛋白.
研究的目的:
- 为了映射A-MuLV.的RNA基因组.
- 为了比较A-MuLV基因组与其假定父,莫洛尼小鼠白血病病毒 (M-MuLV).
- 在A-MuLV基因组中识别同源和独特的序列.
主要方法:
- 使用来自M-MuLV的DNA探针进行异质双重映射.
- 电子显微镜用全长的M-MuLVDNA形成的异质复合体.
- 在标记为M-MuLV DNA和A-MuLV RNA之间的混合物中S1核酶的消化.
- 对消化的碎片进行电泳分析,以确定同质长度.
主要成果:
- A-MuLV和M-MuLV在它们的RNA的5' (1320核酸) 和3' (730核酸) 末端共享同源序列.
- A-MuLV基因组的中心部分与M-MuLVRNA.不同类.
- 从M-MuLVRNA中删除了大约6200个核酸,并用A-MuLV基因组中的3600个核酸插入物取代.
结论:
- A-MuLV基因组是一个由M-MuLV.衍生的重组分子.
- A-MuLV RNA的中央独特区域很可能来自正常的小鼠基因组.
- 这种基因组结构解释了A-MuLV与M-MuLV.相比的独特特性.
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