GAP JUNCTION

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子项目和研究者（PI）可能从另一个NIH来源获得主要资金，因此可以在其他CRISP条目中表示。所列机构为中心，不一定是研究者所在机构。缝隙连接（GJs）代表了所有多细胞动物的普遍存在的组成部分，GJs是第一个通过电子晶体学方法检查的标本之一。然而，这些晶体中的大多数（99.9%）具有良好的短程有序性和长程无序性，这导致相干衍射数据通常仅约为~15-25 μ m。结果，在> 10 μ m处仅获得一个3D结构（Unger等人，1999年）。这是一个重要的一点，因为目标之一是重新发明图像处理程序，使我们能够获得基于混合晶体学/单粒子重建方法的结构数据，以获得更大的通量。此外，我们已经发现，有几类有趣的连接蛋白功能突变体，其中六聚体或十二聚体在保持在膜内时是稳定的，但在去污剂溶解时解离。对于这些突变体，高分辨率结构的结晶将永远不可能。我们开始开发结合晶体学信息和单粒子重建方法的图像处理混合方法，因此它对晶格有序的依赖性要小得多。

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. Gap junctions (GJs) represent a ubiquitous component of all multicellular animals, and GJ s were one of the first specimens examined by electron crystallographic methods. However, the majority (99.9%) of these crystals have good short range order combined with long range disorder that results in coherent diffraction data generally only to about ~15-25 ¿. As a result, there is only one 3D structure obtained at > 10 ¿ (Unger et al., 1999). This is an important point because one of the aims is to reinvent image processing procedures that would allow us to obtain structural data based on a hybrid crystallographic/single particle reconstruction approach for greater throughput. Furthermore, we have found that there are classes of interesting connexin functional mutants where the hexamer or dodecamer is stable when held within the membrane, but dissociates upon detergent solubilization. For these mutants, crystallization for a high resolution structure will never be possible. We began development of hybrid methods of image processing combining crystallographic information with single particle reconstruction methods so it is much less dependent on lattice order.