SP071 function in morphogenesis during spore development

描述（由申请人提供）：本项目的目标是了解隔膜细胞骨架和脂质组成如何调节膜形态。为了研究这个问题，我们以酿酒酵母的前体膜为模型。在产孢过程中，母细胞内产生四个新细胞，因为前祖膜生长以包裹减数分裂核。最终，前殖膜将作为孢子壁沉积的模板，其内部小叶将成为新的单倍体细胞的质膜。酵母膜的合成对于酵母形成功能性的、环境抗性的孢子是必不可少的。我们的长期目标是了解细胞结构的调控。提出的研究将有助于我们理解重要的分子机制，以形成一个重要的细胞结构（前体膜）的完整性和形式的酵母减数分裂产物。本提案中的工作将提供关于细胞和细胞结构如何获得其形状的细胞生物学基本方面的见解，并将有助于我们对septin的理解，septin是与真菌和动物中发现的膜相关的丝形成蛋白。在之前的资助期内，Spo71蛋白被发现对确定前囊膜的大小很重要，并且是沿前囊膜正确定位蛋白酶所必需的。初步研究表明，SPO71在前体膜发育的伸长阶段起重要作用。本实验专门研究了septin和septin调节因子在prospore膜发育中的作用，并研究了膜脂组成如何被调节并有助于prospore膜的形态发生。这些研究将区分这些蛋白质如何共同调节PSM大小和形状的模型。由于septin蛋白是一个进化上保守的蛋白家族，对多种细胞过程（包括细胞分裂、免疫功能和神经元发育）至关重要，并且由于膜组成对膜形态的影响是细胞生物学的一个基本问题，因此这些研究的发现应该引起广泛生物学家的兴趣。

DESCRIPTION (provided by applicant): The goal of this project is to understand how membrane morphology is regulated by the septin cytoskeleton and by lipid composition. To study this question, we use the S. cerevisiae prospore membrane as a model. During sporulation, four new cells are generated within the mother cell as the prospore membrane grows to encapsulate the meiotic nuclei. Ultimately, the prospore membrane will act as the template for the deposition of the spore wall, and its inner leaflet will become the plasma membrane for the new haploid cells. Synthesis of the prospore membrane is essential for yeast to form functional, environmentally resistant spores. Our long-term goal is to understand the regulation of cellular architecture. The proposed research will contribute to our understanding of the molecular mechanisms important for shaping a cellular structure (the prospore membrane) important for the integrity and form of the yeast's meiotic products. The work in this proposal wil provide insights into fundamental aspects of cell biology concerning how cells and cellular structures acquire their shapes, and will also contribute to our understanding of septins, which are filament- forming proteins associated with membranes found in fungi and animals. In the previous funding period, the Spo71 protein was found to be important for determining the size of the prospore membrane and to be required for proper localization of septins along the prospore membrane. Preliminary studies suggest SPO71 is important in the elongation phase of prospore membrane development. The proposed experiments specifically examine the role of septins and septin regulators in prospore membrane development, and also examine how membrane lipid composition is regulated and contributes to prospore membrane morphogenesis. These studies will distinguish models for how these proteins work together to regulate PSM size and shape. As septins are an evolutionarily conserved protein family vital for a variety of cellular processes (including cell division, immune function, and neuronal development) and because the effect of membrane composition on membrane morphology is a fundamental issue in cell biology, the findings from these proposed studies should be of interest to a wide range of biologists.