The long-term objective of this application is to develop methods for the efficient determination of atomic- resolution three-dimensional (3D) structures of large biological complexes in their native, non-crystalline states. The emerging technology of cryo-electron microscopy and 3D reconstruction (collectively """"""""cryoEM"""""""") offers great promise for such structural studies. In the current funding period, the PI's group has developed data processing methods, implemented software, and validated these advances by determination of cryoEM structures of a number of large complexes to near-atomic resolution. We hypothesize that improvements in cryoEM technique, coupled with powerful computational tools, can be developed to create and process terabytes of image data for determination of atomic models of large complexes. Whereas we aimed and succeeded in the current funding period to obtain cryoEM structures at near-atomic resolution, the overall goal of this renewal application is to obtain structures at atomic resolution. In the renewal, we propose to improve both imaging itself and computation to bring resolution to 2.5E, permitting identification of amino acids and ultimately atomic resolution. In the renewal period, we therefore focus on improvement of imaging and methods for image acquisition and correction (Aim #1), making cryoEM structure determination hundreds of times more efficient and affordable (Aim #2), extending our success with icosahedral objects to helical ones (Aim #3), improvement of cryoEM-specific atomic-model refinement software that takes advantage of phase as well as amplitude data and that can handle the vastly greater amounts of data required for atomic resolution 3D reconstruction (Aim #4), and validation by applying these new methods for atomic structure determination to a small icosahedral hepatitis B virus (HBV) core, a large icosahedral aquareovirus and the helical tobacco mosaic virus (TMV) (Aim #5). Our overriding principle in achievement of all of these aims is that the optimized methods we create should permit them to be used routinely, reproducibly, and affordably. A successful outcome of this renewal project will remove the final obstacles towards determination of atomic- resolution structures for large complexes by cryoEM and will have great impact on many areas of biomedical research. This achievement will complement other structural methods, particularly X-ray crystallography of purified proteins that are amenable to crystallization and NMR of small molecules in solution. Specifically, this achievement will enable investigators to place individual proteins within the structural context of the larger assembly and to visualize native shapes and physical chemical interactions among the parts of the complex. Moreover, the ability to look at large complexes at atomic resolution will permit visualization of complexes bound to antibodies, receptors, and drugs.
This continuation project builds on the current success in reaching near-atomic resolution cryo-electron microscopy and aims to make atomic resolution structure determination a routine practice for large biological complexes. Realization of this goal will have far-reaching impact on multiple biomedical areas including structural biology, biochemistry, cell biology, virology, pathology, and molecular medicine. A successful outcome of this project will create a new paradigm for the entire biological structure community. Atomic- resolution cryoEM would also serve the mission of NIH by speeding up structural studies of disease mechanisms and by generating atomic information for rational drug design.
|Yu, Xuekui; Jih, Jonathan; Jiang, Jiansen et al. (2017) Atomic structure of the human cytomegalovirus capsid with its securing tegument layer of pp150. Science 356:|
|Dai, Xinghong; Wu, Lily; Sun, Ren et al. (2017) Atomic Structures of Minor Proteins VI and VII in the Human Adenovirus. J Virol :|
|Liu, Shiheng; Li, Xueni; Zhang, Lingdi et al. (2017) Structure of the yeast spliceosomal postcatalytic P complex. Science 358:1278-1283|
|Li, Xueni; Liu, Shiheng; Jiang, Jiansen et al. (2017) CryoEM structure of Saccharomyces cerevisiae U1 snRNP offers insight into alternative splicing. Nat Commun 8:1035|
|Grintsevich, Elena E; Ge, Peng; Sawaya, Michael R et al. (2017) Catastrophic disassembly of actin filaments via Mical-mediated oxidation. Nat Commun 8:2183|
|Liu, Yun-Tao; Jiang, Jiansen; Bohannon, Kevin Patrick et al. (2017) A pUL25 dimer interfaces the pseudorabies virus capsid and tegument. J Gen Virol 98:2837-2849|
|Dai, Xinghong; Li, Zhihai; Lai, Mason et al. (2017) In situ structures of the genome and genome-delivery apparatus in a single-stranded RNA virus. Nature 541:112-116|
|Poweleit, Nicole; Ge, Peng; Nguyen, Hong H et al. (2016) CryoEM structure of the Methanospirillum hungatei archaellum reveals structural features distinct from the bacterial flagellum and type IV pilus. Nat Microbiol 2:16222|
|Zhang, Xing; Lai, Mason; Chang, Winston et al. (2016) Structures and stabilization of kinetoplastid-specific split rRNAs revealed by comparing leishmanial and human ribosomes. Nat Commun 7:13223|
|Toso, Daniel B; Javed, Muhammad Mohsin; Czornyj, Elizabeth et al. (2016) Discovery and Characterization of Iron Sulfide and Polyphosphate Bodies Coexisting in Archaeoglobus fulgidus Cells. Archaea 2016:4706532|
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