LIGAND-INDUCED CONFORMATIONAL DYNAMICS IN ANDROGEN RECEPTOR & CO-ACTIVATORS

这个子项目是许多利用 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 配体诱导的雄激素受体（AR）构象扰动在辅激活因子募集和反式激活中很重要。然而，与激动剂结合相关的AR配体结合域（AR-LBD）的分子重排及其动力学和热力学参数知之甚少。该研究正在测试这样的假设，即受体构象在没有配体的情况下是灵活的，但在配体结合时达到独特的能量稳定形式。LFD核心设施是我们具体目标的核心。我们正在利用稳态二阶导数吸收和发射光谱，压力和温度扰动，以及bis-ANS分配来研究内在酪氨酸和色氨酸残基的微环境变化，并确定DHT结合后AR-LBD构象变化的动力学和热力学。通过与西奥多哈兹莱特博士合作，FCS和共聚焦成像能力使我们能够检查，第一次，配体的化学计量：受体相互作用和动力学的重组在蛋白质结构的配体结合。

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. Ligand-induced conformational perturbations in androgen receptor (AR) are important in coactivator recruitment and transactivation. However, molecular rearrangements in AR ligand binding domain (AR-LBD) associated with agonist binding and their kinetic and thermodynamic parameters are poorly understood. The study is testing the hypothesis that receptor conformation is flexible in the absence of ligand but achieves a distinct, energetically stable form upon ligand binding. LFD core facilities are central to our specific aims. We are utilizing steady state second derivative absorption and emission spectroscopy, pressure and temperature perturbations, and bis-ANS partitioning to investigate changes in microenvironment of intrinsic tyrosine and tryptophan residues and determine the kinetics and thermodynamics of the conformational changes in AR-LBD after DHT binding.FCS and confocal imaging capabilities available through collaboration with Dr. Theodore Hazlett are allowing us to examine, for the first time, the stoichiometry of ligand:receptor interactions and dynamics of rearrangement in the protein structure upon ligand binding.