在体外从原生Ure2p中启动子域的粉样蛋白形成
K L Taylor1, N Cheng, R W Williams
1Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0830, USA.
Science (New York, N.Y.)
|February 26, 1999
概括
酵母中的[URE3]是由Ure2p蛋白粉样纤维的自我传播解释的. 这些由Ure2p碎片形成的粉样蛋白结构可以诱导本地Ure2p的聚合,模仿子的行为.
科学领域:
- 分子生物学分子生物学
- 蛋白质的生物化学 蛋白质的生物化学
- 酵母遗传学 酵母遗传学
背景情况:
- 在Saccharomyces cerevisiae中的[URE3]元素是一种非门德尔遗传因子.
- 它代表了Ure2p蛋白的传染性子形式,Ure2p蛋白是分解的关键调节者.
研究的目的:
- 为了研究[URE3]子形成的结构基础.
- 阐明Ure2p形成粉样纤维和传播的机制.
主要方法:
- 合成Ure2p碎片 (Ure2p1-65) 和诱导聚合.
- 使用电子显微镜和刚果红色染色对线丝结构的分析.
- 研究合成碎片与全长本地Ure2p.的共聚合.
- 评估形成的纤维的蛋白酶抗性.
主要成果:
- 合成的Ure2p1-65形成了粉状纤维 (40-45 Å直径,>60%的β片).
- 2p1-65诱导原生2p的聚合,形成抗蛋白酶的纤维 (180-220 Å直径).
- 这些辅导纤维种植了本地Ure2p进一步聚合成更厚的纤维,这是粉样蛋白的特征.
结论:
- 由Ure2p形成的自我传播的粉样蛋白解释了[URE3]的传染性.
- N端片段 (Ure2p1-65) 对于启动和传播Ure2p粉样蛋白形成至关重要.
- 氨基代提供了酵母中非门德尔遗传的分子机制.
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