Measuring Phagosomal Temperatures

描述(申请人提供)：细胞内温度梯度调节细胞功能吗？酶反应是依赖温度的，这是我们理解生物化学的基础，但我们倾向于假设细胞内的温度梯度，如果它们发生的话，必须迅速消散，以至于不重要。我们假设，在调节细胞功能方面，细胞内温度梯度可能与离子梯度(如Ca++或pH)一样重要。解决这一问题的挑战是建立在亚细胞水平上测量温度有意义变化的方法，并确定一个生物过程，在其中可以很容易地评估这一假设的温度调节的作用。我们正在开发测量巨噬细胞亚细胞温度变化的方法，并将这些测量应用于吞噬过程，吞噬过程是一个强烈激活细胞的过程，在这个过程中，降解酶被招募来杀死潜在的威胁微生物。提供的初步数据表明，发生了显著的“吞噬体热”。该项目的创新之处在于，细胞内温度变化尚未被认为是调节细胞功能的重要因素。通过这个项目，我们打算为我们对分子和细胞生物学调控机制的理解增加一种新的信号传递方法。所开发的方法将适用于所有分子和细胞生物学领域。

DESCRIPTION (provided by applicant): Do intracellular temperature gradients regulate cellular functions? It is fundamental to our understanding of biochemistry that enzymatic reactions are temperature-dependent, yet we tend to presume that intracellular temperature gradients, if they occur at all, must be dissipated so quickly as to be inconsequential. We hypothesize that intracellular temperature gradients may be as significant as ion gradients (e.g. Ca++ or pH) in regulating cellular functions. The challenge in addressing this question is to establish methodology for measuring meaningful changes in temperature at the subcellular level and to identify a biological process in which the role of this hypothesized temperature regulation can readily be assessed. We are developing methodology for measuring subcellular temperature changes in macrophages and applying these measurements to the process of phagocytosis, a process that strongly activates the cells and one in which degradative enzymes are enlisted to kill potentially threatening microbes. Preliminary data presented demonstrate that significant "Phagosomal Heating" occurs. The project is innovative in that intracellular temperature variations have not yet been implicated as important for regulating cellular functions. With this project, we intend to add a novel method of signaling to our understanding of molecular and cellular biology regulatory mechanisms. The approaches developed will be applicable to all areas molecular and cellular biology.