CRCNS: Computational and experimental study of dopamine and serotonin transporter

这项CRCNS拨款申请提出了质膜多巴胺(DAT)和5-羟色胺转运体(SERT)的结构、功能和动态研究。最近，随着同源亮氨酸转运蛋白的结晶，鉴定DAT和SERT底物和抑制剂结合位点的艰难过程得到了意想不到的推动。这种晶体结构显示了与亮氨酸底物相邻的跨膜(TM)1和6的铰链区，TM 3、8和10也描绘了结合口袋。通过比较分子建模技术，我们已经发布了使用LeuTAa的DAT的三维模型。该模型还提出了与多巴胺不完全相同的新的抑制剂结合部位，可以通过分子药理学技术进行测试。 该项目汇集了一个由计算科学家、药物化学家和药理学家组成的独特团队，以检查单胺神经转运体(MAT)的结构、功能和动力学。 这个项目的总体目标是确定神经递质运输的精神刺激剂和抗抑郁药抑制剂的结合位置，以及参与运输机制的构象状态。 在对接、先进的分子动力学模拟、定量构效关系和基于结构的设计领域的最先进的计算技术将被用来识别转运体的重要残基和区域，以执行突变实验以及指导抑制结合的新化合物的合成。 非神经递质分子的数量仍然保持着转运蛋白的活性。 总之，这项建议(1)包括计算和/或建模专家(Madura研究小组)、实验神经药物学家(Surratt研究小组)和药物化学家(Lapinsky研究小组)之间的合作；(2)涉及这些研究小组在模型开发和神经转运体完善方面的激烈、动态的互动；以及(3)导致开发和测试新的模型，这些模型为实验设计和产生新的假说提供框架，以揭示正常神经系统疾病状态下的机制。

This CRCNS grant application proposes structure, function, and dynamic studies on the plasma membrane dopamine (DAT) and serotonin transporters (SERT). Recently, the arduous process of identifying DAT and SERT substrate and inhibitor binding sites received an unexpected boost with the crystallization of the homologous LeuTAa leucine transporter. This crystal structure revealed hinged regions of transmembranes (TMs) 1 and 6 adjacent to the leucine substrate, with TMs 3, 8 and 10 also delineating the binding pocket. Through comparative molecular modeling techniques we have published a three-dimensional model of DAT using LeuTAa. The modeling also suggests novel inhibitor binding sites, nonidentical to dopamine, that can be tested via molecular pharmacological techniques. This project brings together a unique team of computational scientists, medicinal chemists, and pharmacologists to examine the structure, function, and dynamics of monoamine neurotransporters (MATs). The overall goal of this project is to determine binding locations for psychostimulant and antidepressant inhibitors of neurotransmitter transport, and the conformational states involved in the transport mechanism. State-of-the-art computational techniques in areas of docking, advanced molecular dynamics simulations, QSAR and structure-based design will be used to identify important residues and regions of the transporter to perform mutagenesis experiments as well as direct the synthesis of novel compounds that inhibit binding of non-neurotransmitter molecules yet retain transporter activity. In summary, this proposal (1) includes collaborations between computational and/or modeling experts (Madura research group), experimental neuropharmacoiogists (Surratt research group) and medicinal chemists (Lapinsky research group); (2) involves intense, dynamic interactions among these research groups in the model development and refinement of neurotransporters; and (3) leads to the development and testing of new models that provide a framework for the design of experiments and the generation of new hypotheses to reveal mechanisms underlying normal nervous system disease states.