GENETIC REGULATION OF PHOSPHOLIPID SYNTHESIS IN YEAST

磷脂合成的遗传调控分析将 在单细胞真核生物酿酒酵母中进行。 一个主要 目标是全面了解监管级联 控制磷脂生物合成的转录调节 结构基因对前体可用性的反应， 磷脂合成 这些研究将涉及隔离和 合成和/或调节缺陷突变体的表征 磷脂。 拟议的研究还涉及详细的分析 编码磷脂的结构基因的转录调控 生物合成酶 四个结构基因和三个调控基因 已被分离并将用于本分析。 的相互作用 反式作用调控基因产物中的顺式作用元件 将详细描述结构基因的启动子。 的 克隆的结构基因也将用于促进对 将磷脂生物合成酶组装成其特异性的 在细胞膜上的位置。 关于真核细胞控制细胞生长的机制， 膜脂的合成与正在进行的膜协调 生物起源 然而，磷脂，特别是含肌醇的磷脂， 磷脂，已经涉及复杂的信号传导过程， 在控制细胞生长和增殖方面发挥作用， 真核生物 酵母细胞合成一种典型的真核混合物， 磷脂，使用的途径，这是类似于那些在较高的 真核生物 这种生物在基因上是容易控制的， 使用强大的分子遗传学。 因此，S.酿酒，提供了一种 这是一个难得的机会，可以全面了解 膜磷脂合成的调控机制 生物发生和细胞生长。

An analysis of genetic regulation of phospholipid synthesis will be conducted in the unicellular eukaryote, Saccharomyces cerevisiae. A major goal is to develop a comprehensive understanding of the regulatory cascade that controls transcriptional regulation of phospholipid biosynthetic structural genes in response to precursor availability and ongoing phospholipid synthesis. The studies will involve isolation and characterization of mutants with defects in the synthesis and/or regulation of phospholipids. The proposed research also involves a detailed analysis of the transcriptional regulation of structural genes encoding phospholipid biosynthetic enzymes. Four structural genes and three regulatory genes have been isolated and will be used in this analysis. The interaction of the trans-acting regulatory gene products with cis-acting elements in the promoters of the structural genes will be characterized in detail. The cloned structural genes will also be used to facilitate studies of the assembly of the phospholipid biosynthetic enzymes into their specific locations in the cellular membranes. Little is known about the mechanisms by which eukaryotic cells control the synthesis of membrane lipids in coordination with ongoing membrane biogenesis. Yet phospholipids, particularly inositol-containing phospholipids, have been implicated in complex signalling processes which play a role in controlling cell growth and proliferation in higher eukaryotes. Yeast cells synthesize a typically eukaryotic mixture of phospholipids, using pathways which are similar to those in higher eukaryotes. The organism is genetically tractable, and can be manipulated using powerful molecular genetics. Therefore, S. cerevisiae, provides an unusual opportunity to develop a comprehensive understanding of the regulatory mechanisms controlling phospholipid synthesis during membrane biogenesis and cell growth.