Chang Wang, Amin Khosrozadeh, Ioan Iacovache, Benoît Zuber
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引用次数: 0
Abstract
Cryo-electron tomography (cryoET) provides 3D datasets of organelles and proteins at nanometer and sub-nanometer resolution. However, locating target proteins in live cells remains a significant challenge. Conventional labeling methods, such as fluorescent protein tagging and immunogold labeling, are unsuitable for small structures in vitrified samples at molecular resolution. Directly linking large, visually identifiable proteins to target proteins may alter their structure, localization, and function. To overcome this, we employed a rapamycin-induced oligomer formation system involving two tags, FK506 binding protein (FKBP) and FKBP-rapamycin binding (FRB), which bind in the presence of rapamycin. FKBP is linked to the target protein, while FRB is linked to ferritin, a large (10–12 nm) iron-binding complex that creates strong contrast in cryoET. Upon adding rapamycin to the cell medium, the iron-loaded ferritin accurately marks the target protein location. As in situ cryoET with subtomogram averaging advances, our method addresses the persistent challenge of locating target proteins in live cells.
期刊介绍:
Structure aims to publish papers of exceptional interest in the field of structural biology. The journal strives to be essential reading for structural biologists, as well as biologists and biochemists that are interested in macromolecular structure and function. Structure strongly encourages the submission of manuscripts that present structural and molecular insights into biological function and mechanism. Other reports that address fundamental questions in structural biology, such as structure-based examinations of protein evolution, folding, and/or design, will also be considered. We will consider the application of any method, experimental or computational, at high or low resolution, to conduct structural investigations, as long as the method is appropriate for the biological, functional, and mechanistic question(s) being addressed. Likewise, reports describing single-molecule analysis of biological mechanisms are welcome.
In general, the editors encourage submission of experimental structural studies that are enriched by an analysis of structure-activity relationships and will not consider studies that solely report structural information unless the structure or analysis is of exceptional and broad interest. Studies reporting only homology models, de novo models, or molecular dynamics simulations are also discouraged unless the models are informed by or validated by novel experimental data; rationalization of a large body of existing experimental evidence and making testable predictions based on a model or simulation is often not considered sufficient.