The regulation of signalling molecules in Saccharomyces Cerevisiae by inositol polyphosphate 5-phosphatases

磷酸肌肽信号分子调节肌动蛋白细胞骨架、分泌、囊泡运输和细胞生长和死亡。我们已经鉴定、克隆和表征了一个信号终止酶家族，称为肌醇多磷酸5-磷酸酶（5-磷酸酶），它调节磷酸肌醇信号分子。我们克隆并鉴定了四种不同的酵母5-磷酸酶，并通过缺失和过表达研究证明这些酶调节肌动蛋白细胞骨架、内吞噬和分泌。本研究计划旨在研究5-磷酸酶与特定肌动蛋白结合和/或调节蛋白形成的信号复合物，研究磷酸肌苷脂质磷酸酶的复杂相互作用及其在调节内质网分泌中的作用，并最终表征我们最近发现的一种新型5-磷酸酶。总的来说，这些研究的结果将提供关于这个重要酶家族调节的功能重要信号通路的新信息。

Phosphoinositide signalling molecules regulate the actin cytoskeleton, secretion, vesicular trafficking and cell growth and death. We have identified, cloned and characterised a family of signal terminating enzymes called inositol polyphosphate 5-phosphatases (5-phosphatases) that regulate phosphoinositide signalling molecules. We have cloned and characterised four distinct 5-phosphatases in the yeast Saccharomyces Cerevisiae and demonstrated by both deletion and overexpression studies that these enzymes regulate the actin cytoskeleton, endocytosis and secretion. This research proposal aims to investigate the signalling complexes the 5-phosphatases form with specific actin binding and or regulatory proteins, investigate the complex interactions of phosphoinositide lipid phosphatases and the roles they play in regulating secretion from the endoplasmic reticulum and finally characterize a novel 5-phosphatase that we have recently identified. Collectively the outcome of these studies will provide novel information about the functionallly significant signalling pathways regulated by this important enzyme family.