2M3C

Solution Structure of gammaM7-Crystallin

2M3C の概要

• エントリーDOI: 10.2210/pdb2m3c/pdb
• NMR情報: BMRB: 18953
• 分子名称: Crystallin, gamma M7 (1 entity in total)
• 機能のキーワード: beta/gamma crystallin, fish lens, structural protein
• 由来する生物種: Danio rerio (leopard danio,zebra danio,zebra fish)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 20937.91

構造登録者

Mahler, B.,Wu, Z. (登録日: 2013-01-16, 公開日: 2013-08-28, 最終更新日: 2024-05-15)

主引用文献

Mahler, B.,Chen, Y.,Ford, J.,Thiel, C.,Wistow, G.,Wu, Z.
Structure and Dynamics of the Fish Eye Lens Protein, gamma M7-Crystallin.
Biochemistry, 52:3579-3587, 2013

PubMed Abstract: The vertebrate eye lens contains high concentrations of crystallins. The dense lenses of fish are particularly abundant in a class called γM-crystallin whose members are characterized by an unusually high methionine content and partial loss of the four tryptophan residues conserved in all γ-crystallins from mammals which are proposed to contribute to protection from UV-damage. Here, we present the structure and dynamics of γM7-crystallin from zebrafish (Danio rerio). The solution structure shares the typical two-domain, four-Greek-key motif arrangement of other γ-crystallins, with the major difference noted in the final loop of the N-terminal domain, spanning residues 65-72. This is likely due to the absence of the conserved tryptophans. Many of the methionine residues are exposed on the surface but are mostly well-ordered and frequently have contacts with aromatic side chains. This may contribute to the specialized surface properties of these proteins that exist under high molecular crowding in the fish lens. NMR relaxation data show increased backbone conformational motions in the loop regions of γM7 compared to those of mouse γS-crystallin and show that fast internal motion of the interdomain linker in γ-crystallins correlates with linker length. Unfolding studies monitored by tryptophan fluorescence confirm results from mutant mouse γS-crystallin and show that unfolding of a βγ-crystallin domain likely starts from unfolding of the variable loop containing the more fluorescently quenched tryptophan residue, resulting in a native-like unfolding intermediate.

PubMed: 23597261
DOI: 10.1021/bi400151c

実験手法

SOLUTION NMR