4IK9

High resolution structure of GCaMP3 dimer form 2 at pH 7.5

4IK9 の概要

• エントリーDOI: 10.2210/pdb4ik9/pdb
• 関連するPDBエントリー: 4IK1 4IK3 4IK4 4IK5 4IK8
• 分子名称: RCaMP, Green fluorescent protein, CALCIUM ION, DI(HYDROXYETHYL)ETHER, ... (4 entities in total)
• 機能のキーワード: calcium indicator, mutants, fluorescent intensity, dimerization, beta-barrel, calmodulin, ca ion, cytpplasm, fluorescent protein
• 由来する生物種: Entacmaea quadricolor (Bubble-tip anemone); 詳細
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 50810.82

構造登録者

Chen, Y.,Song, X.,Miao, L.,Zhu, Y.,Ji, G. (登録日: 2012-12-25, 公開日: 2014-01-29, 最終更新日: 2017-06-21)

主引用文献

Chen, Y.,Song, X.,Ye, S.,Miao, L.,Zhu, Y.,Zhang, R.G.,Ji, G.
Structural insight into enhanced calcium indicator GCaMP3 and GCaMPJ to promote further improvement.
Protein Cell, 4:299-309, 2013

PubMed Abstract: Genetically encoded Ca(2+) indicators (GECI) are important for the measurement of Ca(2+) in vivo. GCaMP2, a widely-used GECI, has recently been iteratively improved. Among the improved variants, GCaMP3 exhibits significantly better fluorescent intensity. In this study, we developed a new GECI called GCaMPJ and determined the crystal structures of GCaMP3 and GCaMPJ. GCaMPJ has a 1.5-fold increase in fluorescence and 1.3-fold increase in calcium affinity over GCaMP3. Upon Ca(2+) binding, GCaMP3 exhibits both monomeric and dimeric forms. The structural superposition of these two forms reveals the role of Arg-376 in improving monomer performance. However, GCaMPJ seldom forms dimers under conditions similar to GCaMP3. St ructural and mutagenesis studies on Tyr-380 confirmed its importance in blocking the cpEGFP β-barrel holes. Our study proposes an efficient tool for mapping Ca(2+) signals in intact organs to facilitate the further improvement of GCaMP sensors.

PubMed: 23549615
DOI: 10.1007/s13238-013-2103-4

実験手法

X-RAY DIFFRACTION (1.8 Å)