4FI9

Structure of human SUN-KASH complex

4FI9 の概要

• エントリーDOI: 10.2210/pdb4fi9/pdb
• 分子名称: SUN domain-containing protein 2, Nesprin-2 (3 entities in total)
• 機能のキーワード: linc complex, transmembrane protein, protein binding
• 由来する生物種: Homo sapiens (human); 詳細
• 細胞内の位置: Nucleus inner membrane; Single-pass type II membrane protein: Q9UH99; Nucleus outer membrane; Single-pass type IV membrane protein; Cytoplasmic side (Potential): Q8WXH0
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 23580.50

構造登録者

Wang, W.J.,Shi, Z.B. (登録日: 2012-06-08, 公開日: 2012-07-18, 最終更新日: 2024-11-20)

主引用文献

Wang, W.,Shi, Z.,Jiao, S.,Chen, C.,Wang, H.,Liu, G.,Wang, Q.,Zhao, Y.,Greene, M.I.,Zhou, Z.
Structural insights into SUN-KASH complexes across the nuclear envelope.
Cell Res., 22:1440-1452, 2012

PubMed Abstract: Linker of the nucleoskeleton and the cytoskeleton (LINC) complexes are composed of SUN and KASH domain-containing proteins and bridge the inner and outer membranes of the nuclear envelope. LINC complexes play critical roles in nuclear positioning, cell polarization and cellular stiffness. Previously, we reported the homotrimeric structure of human SUN2. We have now determined the crystal structure of the human SUN2-KASH complex. In the complex structure, the SUN domain homotrimer binds to three independent "hook"-like KASH peptides. The overall conformation of the SUN domain in the complex closely resembles the SUN domain in its apo state. A major conformational change involves the AA'-loop of KASH-bound SUN domain, which rearranges to form a mini β-sheet that interacts with the KASH peptide. The PPPT motif of the KASH domain fits tightly into a hydrophobic pocket on the homotrimeric interface of the SUN domain, which we termed the BI-pocket. Moreover, two adjacent protomers of the SUN domain homotrimer sandwich the KASH domain by hydrophobic interaction and hydrogen bonding. Mutations of these binding sites disrupt or reduce the association between the SUN and KASH domains in vitro. In addition, transfection of wild-type, but not mutant, SUN2 promotes cell migration in Ovcar-3 cells. These results provide a structural model of the LINC complex, which is essential for additional study of the physical and functional coupling between the cytoplasm and the nucleoplasm.

PubMed: 22945352
DOI: 10.1038/cr.2012.126

実験手法

X-RAY DIFFRACTION (3.05 Å)