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-Structure paper
タイトル | Structural basis of assembly chaperone- mediated snRNP formation. |
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ジャーナル・号・ページ | Mol Cell, Vol. 49, Issue 4, Page 692-703, Year 2013 |
掲載日 | 2013年2月21日 |
著者 | Clemens Grimm / Ashwin Chari / Jann-Patrick Pelz / Jochen Kuper / Caroline Kisker / Kay Diederichs / Holger Stark / Hermann Schindelin / Utz Fischer / |
PubMed 要旨 | Small nuclear ribonucleoproteins (snRNPs) represent key constituents of major and minor spliceosomes. snRNPs contain a common core, composed of seven Sm proteins bound to snRNA, which forms in a step- ...Small nuclear ribonucleoproteins (snRNPs) represent key constituents of major and minor spliceosomes. snRNPs contain a common core, composed of seven Sm proteins bound to snRNA, which forms in a step-wise and factor-mediated reaction. The assembly chaperone pICln initially mediates the formation of an otherwise unstable pentameric Sm protein unit. This so-called 6S complex docks subsequently onto the SMN complex, which removes pICln and enables the transfer of pre-assembled Sm proteins onto snRNA. X-ray crystallography and electron microscopy was used to investigate the structural basis of snRNP assembly. The 6S complex structure identifies pICln as an Sm protein mimic, which enables the topological organization of the Sm pentamer in a closed ring. A second structure of 6S bound to the SMN complex components SMN and Gemin2 uncovers a plausible mechanism of pICln elimination and Sm protein activation for snRNA binding. Our studies reveal how assembly factors facilitate formation of RNA-protein complexes in vivo. |
リンク | Mol Cell / PubMed:23333303 |
手法 | EM (単粒子) / X線回折 |
解像度 | 1.898 - 20.0 Å |
構造データ | EMDB-2102: PDB-4f7u: PDB-4v98: |
化合物 | ChemComp-P6G: ChemComp-HOH: ChemComp-SO4: |
由来 |
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キーワード | SPLICING / Assembly Machine / Complex / Assembly Machinery |