SNARE complex formation in living cells

细胞能够通过高度调控的胞吐作用相互传递信息。 胞吐作用允许细胞向细胞外释放激素、神经递质和其他化学物质。 通过将囊泡输送到细胞表面，与质膜融合并释放其 内容。SNARE蛋白对膜融合的调节是必不可少的，它通过形成一种 囊泡上的蛋白质和质膜上的蛋白质之间的复合体 膜紧密相连。这项拟议的工作旨在确定 活体INS-1细胞中SNARE复合体的形成：(1)表征SNARE的依赖性 前复合体对突触素和突触素I浓度的影响，(2)识别哪些前复合体 促进胞吐作用。所提出的实验提供了一种直接测量圈套复合体的方法。 以及通过使用荧光标记的陷阱进行胞吐，该陷阱将使用全内反射照明 显微镜。最终，这些结果可能会揭示，分泌的控制部分取决于相对的 一个单元格中存在的陷阱数量。

Cells are able to transmit information to each other via the highly regulated process of exocytosis. Exocytosis allows cells to release hormones, neurotransmitters, and other chemicals into the extracellular space by transporting a vesicle to the cell surface that fuses with the plasma membrane and releases its contents. SNARE proteins are essential for the regulation of membrane fusion and do so by forming a complex between proteins on the vesicle and proteins on the plasma membrane that brings the two membranes in close proximity. The proposed work is designed to determine the molecular mechanism of SNARE complex formation in living INS-1 cells by: (1) characterizing the dependence of SNARE pre-complexes on syntaxin and synaptotagmin I concentration, (2) identifying which pre-complexes facilitate exocytosis. The proposed experiments offer a method of directly measuring SNARE complexes and exocytosis by using fluorescently labeled SNAREs that will be illuminated using total internal reflection microscopy. Ultimately, these results could reveal that control of secretion partially lies in the relative amounts of SNAREs present in a cell.