Regulation of Acetylcholine Receptors on Muscle

我们对突变斑马鱼的研究继续推进对突触传递和遗传的理解 人类神经肌肉疾病的形式，如肌无力综合征、慢通道综合征和Brody 疾病。拟议的研究现在利用了突变系，我们已经证明这些突变系要么缺乏突触 完全传递，或缺乏受体定位突触下的能力，肌肉的能力 释放钙，肌肉隔离钙的能力，或具有异常水平的突触驱动 提示突触前神经和突触后肌肉之间存在沟通障碍。利用 优势，我们将确定突触活动在塑造两者中的作用 突触前和突触后发育。利用我们最近的研究将极大地促进这些研究 开发了系留毒素方法学，以细胞自主的方式沉默突触传递。 因此，我们可以确定调整单个细胞的突触驱动和/或兴奋性的后果 在运动神经元靶场内。挽救突变系中的单个突触后细胞将提供一种 一种互补的方法，即单个细胞在目标肌肉的安静区域中被激活。 这两种方法的结合将被用来确定突触后活动在 发育性电耦合丧失，获得突触前递质释放特性和 突触后受体动力学的建立。由于我们的能力，这项研究第一次成为可能 在任何脊椎动物的制备中，同时记录来自运动神经元和活体中的靶肌肉。这 是由于电子致密的肌肉，允许全电池电压钳制和透明，便于 脊髓深处运动神经元的识别和膜片钳。将以下各项优势结合起来 新的方法和准备现在提供了独特的机会或审查长期存在的问题 突触功能。

Our studies of mutant zebrafish continue to advance understanding of synaptic transmission and inheritable forms of human neuromuscular disorders such as myasthenic syndrome, slow channel syndrome and Brody disease. The proposed studies now capitalize on mutant lines which we have shown either lack synaptic transmission altogether, or lack the ability of receptors to localize subsynaptically, the ability of muscle to release calcium, the ability of muscle to sequester calcium, or possess abnormal levels of synaptic drive suggesting miscommunication between presynaptic nerve and postsynaptic muscle. Exploiting the advantages provided by these lines, we will determine the role of synaptic activity in shaping both presynaptic and postsynaptic development. These studies will be greatly facilitated by use of our recently developed tethered toxin methodology that silences synaptic transmission in a cell autonomous fashion. Thus, we can determine the consequences of adjusting synaptic drive and/or excitability of individual cells within the motorneuron target field. Rescue of individual postsynaptic cells in mutant lines will provide a complementary approach wherein a single cell is rendered active in an otherwise silent field of target muscle. This combination of approaches will be used to determine the involvement of postsynaptic activity in the developmental loss of electrical coupling, acquisition of presynaptic transmitter release properties and establishment of postsynaptic receptor kinetics. The study is possible by virtue of our ability, for the first time in any vertebrate preparation, to simultaneously record from a motorneuron and target muscle in vivo. This is due to electrically compact muscle that allows whole cell voltage clamp and transparency, facilitating identification and patch clamp of motorneurons deep within the spinal cord. The combined advantages of new approaches and preparation now provide unique opportunities or examining long standing questions of synaptic function.