1TF7

Crystal Structure of Circadian Clock Protein KaiC

1TF7 の概要

• エントリーDOI: 10.2210/pdb1tf7/pdb
• 分子名称: KaiC, ADENOSINE-5'-TRIPHOSPHATE (3 entities in total)
• 機能のキーワード: homohexamer, hexamer, circadian clock protein
• 由来する生物種: Synechococcus sp.
• タンパク質・核酸の鎖数: 6
• 化学式量合計: 359496.18

構造登録者

Pattanayek, R.,Wang, J.,Mori, T.,Xu, Y.,Johnson, C.H.,Egli, M. (登録日: 2004-05-26, 公開日: 2004-08-24, 最終更新日: 2024-02-14)

主引用文献

Pattanayek, R.,Wang, J.,Mori, T.,Xu, Y.,Johnson, C.H.,Egli, M.
Visualizing a Circadian Clock Protein; Crystal Structure of KaiC and Functional Insights
Mol.Cell, 15:375-388, 2004

PubMed Abstract: Circadian (daily) biological clocks express characteristics that are difficult to explain by known biochemical mechanisms, and will ultimately require characterizing the structures, functions, and interactions of their molecular components. KaiC is an essential circadian protein in cyanobacteria that forms the core of the KaiABC clock protein complex. We report the crystal structure of the KaiC homohexameric complex at 2.8 A resolution. The structure resembles a double doughnut with a central pore that is partially sealed at one end. The crystal structure reveals ATP binding, inter-subunit organization, a scaffold for Kai-protein complex formation, the location of critical KaiC mutations, and evolutionary relationships to other proteins. A key auto-phosphorylation site on KaiC (T432) is identified from the crystal structure, and mutation of this residue abolishes circadian rhythmicity. The crystal structure of KaiC will be essential for understanding this circadian clockwork and for establishing its links to global gene expression.

PubMed: 15304218
DOI: 10.1016/j.molcel.2004.07.013

実験手法

X-RAY DIFFRACTION (2.8 Å)