HEAT-SENSITIVE MUTANTS IN ENDOCYTIC FUNCTION

内吞功能中的热敏突变体

• 批准号: 3285031
• 负责人: ROCKFORD Keith DRAPER
• 金额: $ 17.12万
• 依托单位: UNIVERSITY OF TEXAS DALLAS
• 依托单位国家: 美国
• 财政年份: 1985
• 资助国家: 美国
• 起止时间: 1985-01-01 至 1990-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3285031
• 关键词: adenosinetriphosphatase; antibody formation; autosomal dominant trait; autosomal recessive trait; binding proteins; cell transformation; chromosome complement; electron microscopy; fluorescence; gel electrophoresis; hamsters; immunofluorescence technique; lethal genes; low density lipoprotein; lysosomes; mixed tissue /cell culture; phagocytosis; pinocytosis; protein biosynthesis; radiotracer; receptor; temperature sensitive mutant; transferrin; vesicle /vacuole

The overall objective of this proposal is to study the molecular mechanisms involved in the process of endocytosis. Our approach is to isolate and characterize animal cell mutants that are deficient in endocytic function. Moreover, we focus specifically on mutants that carry conditional-lethal defects. The agents that we use to isolate the mutants are highly potent protein toxins that require endocytic functions to express their lethal activities. Our specific aims are three-fold: 1. Further studies on G.7.1, a Chinese hamster ovary cell mutant carrying a conditional-lethal defect in endocytic function: We have so far isolated two mutants that at elevated temperature (39.5 C) lose viability and in the process become resistant to protein toxins. We have studied one of these mutants, called G.7.1, in more detail and the results suggest that it contains a heat-sensitive lesion affecting vacuolar acidification. We propose to more precisely identify the lesion in this mutant and to use the mutant as a model to investigate what effect the lesion has on endocytic processes. 2. Isolation and characterization of more mutants: Our selection procedure is capable of rescuing many different kinds of mutants containing conditional-lethal defects in endocytic function. We propose to search for, and characterize, additional mutants. 3. Genetic characterization of mutants: With techniques of somatic cell genetics we will determine whether the lesions in our mutants are expressed dominantly or recessively. Mutants that contain recessive lesions will be classified into complementation groups. We also propose to isolate and characterize revertants of the mutants.

该提议的总体目的是研究分子机制 参与内吞作用过程。 我们的方法是孤立和 表征缺乏内吞作用的动物细胞突变体。 此外，我们专门关注携带有条件致命的突变体 缺陷。 我们用来隔离突变体的代理非常有效 需要内吞作用以表达其致命的蛋白质毒素 活动。 我们的具体目的是三个方面： 1。对G.7.1的进一步研究，一种携带A的中国仓鼠卵巢突变体 内吞功能中的条件致命缺陷：我们到目前为止孤立 在温度升高（39.5 c）处的两个突变体失去生存力，在 过程对蛋白质毒素具有抗性。 我们研究了其中之一 更详细地称为G.7.1的突变体，结果表明它 包含影响液泡酸化的热敏感病变。 我们 提议更精确地识别该突变体中的病变并使用 突变体作为研究病变对内吞作用的影响 过程。 2。更多突变体的隔离和表征：我们的选择程序 能够营救许多包含的突变体 内吞功能中有条件的致命缺陷。 我们建议搜索 为了和表征其他突变体。 3。突变体的遗传表征：带有体细胞技术 遗传学我们将确定突变体中的病变是否表达 主导或幕后。 包含隐性病变的突变体将是 分类为互补组。 我们还建议分离和 表征突变体的恢复物。