4XRI

Crystal Structure of Importin Beta in an Ammonium Sulfate Condition

4XRI の概要

• エントリーDOI: 10.2210/pdb4xri/pdb
• 関連するPDBエントリー: 4XRK
• 分子名称: Putative uncharacterized protein, SULFATE ION, GLYCEROL, ... (4 entities in total)
• 機能のキーワード: transport protein, nuclear transport, transport receptor, importin-beta superfamily, heat repeat protein, nuclear import of various proteinaceous cargo molecules, highly flexible proteins
• 由来する生物種: Chaetomium thermophilum (strain DSM 1495 / CBS 144.50 / IMI 039719)
• 細胞内の位置: Nucleus : G0S143
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 98326.24

構造登録者

Tauchert, M.J.,Neumann, P.,Ficner, R.,Dickmanns, A. (登録日: 2015-01-21, 公開日: 2016-01-27, 最終更新日: 2024-01-10)

主引用文献

Tauchert, M.J.,Hemonnot, C.,Neumann, P.,Koster, S.,Ficner, R.,Dickmanns, A.
Impact of the crystallization condition on importin-beta conformation.
Acta Crystallogr D Struct Biol, 72:705-717, 2016

PubMed Abstract: In eukaryotic cells, the exchange of macromolecules between the nucleus and cytoplasm is highly selective and requires specialized soluble transport factors. Many of them belong to the importin-β superfamily, the members of which share an overall superhelical structure owing to the tandem arrangement of a specific motif, the HEAT repeat. This structural organization leads to great intrinsic flexibility, which in turn is a prerequisite for the interaction with a variety of proteins and for its transport function. During the passage from the aqueous cytosol into the nucleus, the receptor passes the gated channel of the nuclear pore complex filled with a protein meshwork of unknown organization, which seems to be highly selective owing to the presence of FG-repeats, which are peptides with hydrophobic patches. Here, the structural changes of free importin-β from a single organism, crystallized in polar (salt) or apolar (PEG) buffer conditions, are reported. This allowed analysis of the structural changes, which are attributable to the surrounding milieu and are not affected by bound interaction partners. The importin-β structures obtained exhibit significant conformational changes and suggest an influence of the polarity of the environment, resulting in an extended conformation in the PEG condition. The significance of this observation is supported by SAXS experiments and the analysis of other crystal structures of importin-β deposited in the Protein Data Bank.

PubMed: 27303791
DOI: 10.1107/S2059798316004940

実験手法

X-RAY DIFFRACTION (2.05 Å)