PLATELET TOMOGRAPHY

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 血小板是由巨噬细胞产生的小细胞碎片(直径3微米，厚1微米)。它们在血液中循环，在初级止血中发挥重要作用。一些血小板缺陷会导致一系列出血性疾病，而另一些则会显著增加血栓事件的风险，如肺栓塞、心脏病发作和中风。血小板天生没有细胞核，这使得它们比典型的真核细胞薄得多，但它们仍然包含线粒体、微管、肌动蛋白细胞骨架和其他真核细胞特征。它们还包含其角色所独有的其他结构。因此，它们是用电子冷冻断层摄影术进行结构分析的极佳靶点。 我们的目标是：1)以3D的形式描述血小板的细胞结构；细胞骨架，包括肌动蛋白和微管；膜系统，包括胞浆和细胞内；其他细胞器，如线粒体；以及大分子机器，如核糖体等；最后，它们之间的关系。2)当被凝血信号激活时，所有这些结构和关系都会改变。我们可以通过建立一个激活的时间进程来观察事件的进展。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Blood platelets are small (3 micron diameter and <1 micron thick) cellular fragments generated from macrophages. They circulate in the bloodstream and play a major role in primary hemostasis. Some platelet defects can lead to an array of bleeding disorders, while others can significantly increase risk for thrombotic events such as pulmonary embolism, heart attack and stroke. Platelets naturally lack nuclei, rendering them much thinner than typical eukaryotic cells, yet they still contain mitochondria, microtubules, an actin cytoskeleton and other eukaryotic features. They also contain other structures unique to their role. Thus they are an excellent target for structural analysis by electron cryotomography. Our goals are 1) to describe the cellular structures of platelets in 3D; the cytoskeleton, including actin and microtubules; the membrane systems, both plasma and intracellular; other organelles such as mitochondria; and macromolecular machines such as ribosomes, etc.; and finally their relationships to each other. 2) All these structures and relationships change upon activation by a clotting signal. We can observe the progression of events by setting up a time course of activation.