2GBL

Crystal Structure of Full Length Circadian Clock Protein KaiC with Phosphorylation Sites

2GBL の概要

• エントリーDOI: 10.2210/pdb2gbl/pdb
• 関連するPDBエントリー: 1TF7 1U9I
• 分子名称: Circadian clock protein kinase kaiC, MAGNESIUM ION, ADENOSINE-5'-TRIPHOSPHATE, ... (5 entities in total)
• 機能のキーワード: circadian clock protein homohexamer, circadian, kaia, kaib, kaic, hexamer, circadian clock protein, transferase
• 由来する生物種: Synechococcus elongatus; 詳細
• タンパク質・核酸の鎖数: 6
• 化学式量合計: 355468.41

構造登録者

Pattanayek, R.,Williams, D.R.,Pattanayek, S.,Xu, Y.,Mori, T.,Johnson, C.H.,Stewart, P.L.,Egli, M. (登録日: 2006-03-10, 公開日: 2007-01-23, 最終更新日: 2024-10-09)

主引用文献

Pattanayek, R.,Williams, D.R.,Pattanayek, S.,Xu, Y.,Mori, T.,Johnson, C.H.,Stewart, P.L.,Egli, M.
Analysis of KaiA-KaiC protein interactions in the cyano-bacterial circadian clock using hybrid structural methods.
Embo J., 25:2017-2028, 2006

PubMed Abstract: The cyanobacterial circadian clock can be reconstituted in vitro by mixing recombinant KaiA, KaiB and KaiC proteins with ATP, producing KaiC phosphorylation and dephosphorylation cycles that have a regular rhythm with a ca. 24-h period and are temperature-compensated. KaiA and KaiB are modulators of KaiC phosphorylation, whereby KaiB antagonizes KaiA's action. Here, we present a complete crystallographic model of the Synechococcus elongatus KaiC hexamer that includes previously unresolved portions of the C-terminal regions, and a negative-stain electron microscopy study of S. elongatus and Thermosynechococcus elongatus BP-1 KaiA-KaiC complexes. Site-directed mutagenesis in combination with EM reveals that KaiA binds exclusively to the CII half of the KaiC hexamer. The EM-based model of the KaiA-KaiC complex reveals protein-protein interactions at two sites: the known interaction of the flexible C-terminal KaiC peptide with KaiA, and a second postulated interaction between the apical region of KaiA and the ATP binding cleft on KaiC. This model brings KaiA mutation sites that alter clock period or abolish rhythmicity into contact with KaiC and suggests how KaiA might regulate KaiC phosphorylation.

PubMed: 16628225
DOI: 10.1038/sj.emboj.7601086

実験手法

X-RAY DIFFRACTION (2.8 Å)