CHOLINE TRANSPORTERS SPECIFICALLY TARGET NON-NEURONAL ACETYLCHOLINE SYNTHESIS

该子项目是利用该技术的众多研究子项目之一 资源由 NIH/NCRR 资助的中心拨款提供。子项目和 研究者 (PI) 可能已从 NIH 的另一个来源获得主要资金， 因此可以在其他 CRISP 条目中表示。列出的机构是 对于中心来说，它不一定是研究者的机构。 非神经元乙酰胆碱（Ach）的合成和分泌可能在肺癌和哮喘等肺部疾病中发挥作用。 为了表征和靶向肺中的非神经元信号传导，有必要确定神经元和非神经元胆碱能信号传导之间不同的步骤。胆碱摄取是乙酰胆碱合成的限速步骤，并且可以提供该目标。在神经元中，钠依赖性高亲和力胆碱转运蛋白 (CHT1) 是将胆碱转运到神经元进行乙酰胆碱合成所必需的。我们的初步数据表明，某些肺细胞不需要 CHT1 来合成 ACh，而是一类新描述的胆碱转运蛋白，即胆碱转运蛋白样蛋白 (CTL1-5)，可以介导 ACh 合成。 因此，通过靶向正确的 CTL，可以潜在地靶向肺中的非神经元 ACh 合成，而不影响神经元 ACh 合成。 为了测试这一点，我们提出以下具体目标：（1）鉴定哪些胆碱转运蛋白样蛋白参与肺非神经元细胞的胆碱摄取。 (2) 鉴定哪种 CTL 与肺中非神经元 ACh 合成偶联。 (3) 确定敲低与乙酰胆碱合成相关的 CTL 是否可以阻止肺细胞增殖。这些目标将通过使用特定的 siRNA 敲除作为肺神经内分泌细胞模型的 H82 小细胞肺癌细胞和作为气道上皮细胞模型的 H520 鳞状细胞肺癌细胞中的 CTL 来实现。因此，这些研究将允许以非神经元乙酰胆碱合成为目标，作为开发肺部疾病新疗法的第一步。

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. Non-neuronal acetylcholine (Ach) synthesis and secretion may play a role in lung diseases such as lung cancer and asthma. In order to characterize and target non-neuronal signaling in lung it is necessary to identify a step that differs between neuronal and non-neuronal cholinergic signaling. Choline uptake is a rate-limiting step for ACh synthesis and may provide this target. In neurons, the sodium-dependent, high-affinity choline transporter (CHT1) is absolutely required to transport choline into neurons for ACh synthesis. Our preliminary data shows that CHT1 is not required by some lung cells for ACh synthesis and that instead a newly described class of choline transporters, the choline transporter-like proteins (CTL1 - 5), can mediate ACh synthesis. Therefore non-neuronal ACh synthesis in lung may potentially be targeted without effecting neuronal ACh synthesis by targeting the correct CTL. To test this we propose the following specific aims: (1) Identification of which choline transporter-like proteins are involved in choline-uptake in lung non-neuronal cells. (2) Identification of which CTL is coupled to non-neuronal ACh synthesis in lung. (3) To determine if knockdown of the CTL linked to ACh synthesis can block lung cell proliferation. These aims will be implemented using specific siRNAs to knock down CTLs in H82 small cell lung carcinoma cells as a model for pulmonary neuroendocrine cells and H520 squamous cell lung carcinoma cells as a model for airway epithelial cells. These studies will thus allow the targeting of non-neuronal ACh synthesis as a first step in developing new therapies for lung diseases.