AXEL BRUNGER PRT TIME

这个子项目是许多研究子项目中的一个 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， 因此可以在其他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。 拟议的实验涉及小蛋白质晶体的表征。 所讨论的蛋白质是两种不同蛋白质的相当大（~500 kDa）的复合物。 晶体在结晶紫染料的存在下染成蓝色，表明它们由蛋白质组成。 然而，晶体仅生长为小板，板面上的尺寸约为100-200微米，垂直于板面测量的尺寸为50微米。对晶体进行研究，以确定衍射、孪生和镶嵌的程度。 还将研究低温条件的潜在改进。 晶体已经在各种不同的衬底中生长。 这些基板上的衍射性能的影响也将进行研究。 空间群的确定和这些晶体的天然集合的收集将是在这个束流时间转移的最终目标。塔瓦雷斯- MAGUK蛋白是组织膜结构域和蛋白信号复合物的重要支架。该家族的成员共享由PDZ结构域、SH 3结构域和鸟苷酸激酶同源结构域组成的共同核心。已经鉴定了这些结构域中的每一个的许多结合伴侣。涉及每个结构域的蛋白质-蛋白质相互作用解释了蛋白质在特定位点的聚集，例如在突触、隔膜和紧密连接、极化上皮细胞的顶端和基底表面，以及膜信号传导途径在胚胎发育期间诱导事件的能力。已经表明，分子内和分子间的相互作用调节MAGUK结构域的构象和结合活性。因此，我们有兴趣在分子水平上研究MAGUK家族的两个成员，以了解这些相互作用的结构基础和对伴侣结合的影响。

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. The proposed experiments involve the characterization of small protein crystals. The protein in question is a fairly large (~500 kDa) complex of two different proteins. The crystals stain blue in the presence of crystal violet dye, indicating that they are composed of protein. However, the crystals grow only as small plates, with dimensions of approximately 100-200 microns on the plate face and 50 microns measured orthogonal to the face. The crystals are to be studied to determine extent of diffraction, twinning and mosaicity. Potential improvements in cryo-conditions will also be examined. The crystals have been grown in a variety of different substrates. The effect of these substrates upon the diffraction properties will be studied as well. Determination of space group and the collection of a native set for these crystals would be the ultimate goal within this shift of beamtime. Tavares - MAGUK proteins are important scaffolds that organize membrane domains and protein signaling complexes. Members of the family share a common core composed of a PDZ domain, a SH3 domain and a guanylate kinase homology domain. Many binding partners for each of these domains have been identified. The protein-protein interactions involving each domain explain the clustering of proteins at specific sites, for instance at synapses, septate and tight junctions, and apical and basal surface of polarized epithelial cells, as well as the ability of membrane signaling pathways to induce events during embryonic development. It has been suggested that intra- and intermolecular interactions regulate conformation and binding activity of MAGUK domains. Therefore we are interested to study at molecular level two members of the MAGUK family in order to understand the structural basis of these interactions and implications for binding of partners.