概括
研究人员使用密度梯度选择确定了新的酵母分泌突变 (sec). 这些突变者积累了蛋白质和有机体,揭示了分泌和细胞表面生长途径的关键步骤.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 在Saccharomyces cerevisiae中的分泌通路缺陷可以通过细胞密度的变化来识别.
- 对温度敏感的突变物对于研究诸如分泌之类的基本细胞过程至关重要.
研究的目的:
- 在酵母中分离和描述新型温度敏感分泌突变物.
- 阐明酵母分泌途径和细胞表面生长中的连续步骤.
主要方法:
- 使用Ludox密度梯度离心法进行突变选择.
- 选条件增长和分泌的逆转酶和酸酶.
- 采用补充分析和电子显微镜用于突变特征.
主要成果:
- 确定了188个突变克隆,分为23个补充组.
- 观察到细胞内逆转酶和分泌器官的温度依赖的积累.
- 在不允许的温度下证明了热可逆的分泌和芽的出现和透活动的停止.
结论:
- 鉴定到的突变提供了关于酵母分泌途径的见解.
- 积累的有机细胞代表分泌和血组合中的中间体.
- 分泌和血组合可能发生在直线上.
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