3GLW

Quaternary Structure of Drosophila melanogaster IC/Tctex-1/LC8; Allosteric Interactions of Dynein Light Chains with Dynein Intermediate Chain

3GLW の概要

• エントリーDOI: 10.2210/pdb3glw/pdb
• 関連するPDBエントリー: 3FM7
• 分子名称: Dynein light chain 1, cytoplasmic, Dynein intermediate Chain (3 entities in total)
• 機能のキーワード: lc8, tctex, tctex-1, intermediate chain, ic, dynein, dynein light chain, entropy, allostery, chelate effect, multivalent., microtubule, motor protein, contractile protein
• 由来する生物種: Drosophila melanogaster (Fruit fly)
• 細胞内の位置: Cytoplasm, cytoskeleton: Q24117
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 13593.41

構造登録者

Hall, J.D.,Karplus, P.A.,Barbar, E.J. (登録日: 2009-03-12, 公開日: 2009-09-15, 最終更新日: 2024-11-20)

主引用文献

Hall, J.,Karplus, P.A.,Barbar, E.
Multivalency in the assembly of intrinsically disordered Dynein intermediate chain.
J.Biol.Chem., 284:33115-33121, 2009

PubMed Abstract: Dynein light chains are thought to increase binding efficiency of dynein intermediate chain to both dynein heavy chain and dynactin, but their exact role is not clear. Isothermal titration calorimetry and x-ray crystallography reported herein indicate that multivalency effects underlie efficient dynein assembly and regulation. For a ternary complex of a 60-amino acid segment of dynein intermediate chain (IC) bound to two homodimeric dynein light chains Tctex1 and LC8, there is a 50-fold affinity enhancement for the second light chain binding. For a designed IC construct containing two LC8 sites, observed the 1000-fold enhancement reflects a remarkably pure entropic chelate effect of a magnitude commensurate with theoretical predictions. The lower enhancement in wild-type IC is attributed to unfavorable free energy changes associated with incremental interactions of IC with Tctex1. Our results show assembled dynein IC as an elongated, flexible polybivalent duplex, and suggest that polybivalency is an important general mechanism for constructing stable yet reversible and functionally versatile complexes.

PubMed: 19759397
DOI: 10.1074/jbc.M109.048587

実験手法

X-RAY DIFFRACTION (3.15 Å)