1MFQ

Crystal Structure Analysis of a Ternary S-Domain Complex of Human Signal Recognition Particle

1MFQ の概要

• エントリーDOI: 10.2210/pdb1mfq/pdb
• 分子名称: 7S RNA of human SRP, signal recognition particle 19kDa protein, signal recognition particle 54kDa protein, ... (6 entities in total)
• 機能のキーワード: rna-protein complex, a-minor motif, 3-helix junction, signaling protein-rna complex, signaling protein/rna
• 由来する生物種: Homo sapiens (human); 詳細
• 細胞内の位置: Cytoplasm: P09132; Nucleus speckle: P61011
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 69053.88

構造登録者

Kuglstatter, A.,Oubridge, C.,Nagai, K. (登録日: 2002-08-13, 公開日: 2002-09-20, 最終更新日: 2024-02-14)

主引用文献

Kuglstatter, A.,Oubridge, C.,Nagai, K.
Induced structural changes of 7SL RNA during the assembly of human signal recognition particle
Nat.Struct.Biol., 9:740-744, 2002

PubMed Abstract: The eukaryotic signal recognition particle (SRP) is a cytoplasmic ribonucleoprotein particle that targets secretory and membrane proteins to the endoplasmic reticulum. The binding of SRP54 to the S domain of 7SL RNA is highly dependent on SRP19. Here we present the crystal structure of a human SRP ternary complex consisting of SRP19, the M domain of SRP54 and the S domain of 7SL RNA. Upon binding of the M domain of SRP54 to the 7SL RNA-SRP19 complex, the asymmetric loop of helix 8 in 7SL RNA collapses. The bases of the four nucleotides in the long strand of the asymmetric loop continuously stack and interact with the M domain, whereas the two adenines in the short strand flip out and form two A-minor motifs with helix 6. This stabilizing interaction is only possible when helix 6 has been positioned parallel to helix 8 by the prior binding of SRP19 to the tetraloops of helices 6 and 8. Hence, the crystal structure of the ternary complex suggests why SRP19 is necessary for the stable binding of SRP54 to the S domain RNA.

PubMed: 12244299
DOI: 10.1038/nsb843

実験手法

X-RAY DIFFRACTION (3.1 Å)