概括
研究人员从感染的仓鼠大脑中鉴定出了尖虫病病原体中主要的蛋白质PrP 27-30. 这种蛋白质是由哺乳动物的单个基因编码的,而不是由传染性疹颗粒本身携带的.
科学领域:
- 神经科学是一个神经科学.
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 疹是一种传染性海绵状脑病.
- 纯化草病剂制剂中的主要蛋白质是PrP 27-30.
- PrP 27-30的起源和遗传基础尚未完全理解.
研究的目的:
- 为了克隆编码PrP 27-30的基因.
- 为了研究PrP 27-30在正常大脑和患有黄病的大脑中的遗传基础.
- 为了确定PrP 27-30是否被核酸编码在鞭毛病子中的核酸.
主要方法:
- 氧核酸探针和cDNA图书馆选以克隆PrP 27-30.
- 南方涂抹用于分析PrP基因.
- 用特定的抗血清进行mRNA分析和西式涂抹.
- 蛋白酶K消化以区分PrP形式.
主要成果:
- 一个编码PrP 27-30的克隆被隔离出了患有脚病的仓鼠大脑.
- 南方斑点检测显示,正常和受感染的子,小鼠和人类DNA中存在单一的PrP基因.
- 与PrP相关的mRNA在正常和感染的大脑和其他组织中存在相似的水平.
- 在正常和受感染的大脑提取物中检测到与PrP相关的蛋白质,但只有PrP 27-30在受感染的大脑中抵抗了蛋白酶K的消化.
- 没有发现与PrP相关的核酸在纯化尖疹原体中.
结论:
- PrP 27-30是由单个宿主基因编码的.
- 在哺乳动物物种中,PrP基因被保存.
- PrP 27-30 是一个宿主蛋白质,并未被疹病原体的核酸编码.
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