SP071 function in morphogenesis during spore development

描述(由申请人提供)：本项目的目标是了解膜形态是如何由隔膜蛋白细胞骨架和脂类成分调节的。为了研究这一问题，我们以酿酒酵母的孢子膜为模型。在孢子形成过程中，随着孢子膜的生长包裹减数分裂核，母细胞内产生了四个新细胞。最终，孢子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。孢子膜的合成对于酵母形成功能性的、环保的孢子是必不可少的。我们的长期目标是了解蜂窝结构的规则。这项拟议的研究将有助于我们理解形成细胞结构(孢子膜)的重要分子机制，该结构对酵母减数分裂产物的完整性和形式至关重要。这项提案中的工作将提供对细胞生物学的基本方面的见解，涉及细胞和细胞结构如何获得其形状，并将有助于我们理解间隔蛋白，这是一种与真菌和动物中发现的膜相关的细丝形成蛋白。在之前的资助时期，Spo71蛋白被发现对决定孢子膜的大小很重要，并且是沿着孢子膜正确定位间隔蛋白所必需的。初步研究表明，SPO71在孢子膜发育的伸长阶段起重要作用。这些实验专门研究了分隔素和分隔素调节剂在孢子膜发育中的作用，并研究了细胞膜的脂成分是如何被调节的，以及对孢子膜的形态发生有何贡献。这些研究将区分这些蛋白质如何共同作用以调节PSM大小和形状的模型。由于Septins是一个进化保守的蛋白质家族，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，而且膜组成对膜形态的影响是细胞生物学中的一个基本问题，因此这些研究的结果应该引起广泛的生物学家的兴趣。

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.