1O9J

The X-ray crystal structure of eta-crystallin

1O9J の概要

• エントリーDOI: 10.2210/pdb1o9j/pdb
• 分子名称: ALDEHYDE DEHYDROGENASE, CYTOSOLIC 1, NICOTINAMIDE-ADENINE-DINUCLEOTIDE, 2,3-DIHYDROXY-1,4-DITHIOBUTANE, ... (5 entities in total)
• 機能のキーワード: aldh, eye-lens protein, eta-crystallin, oxidoreductase
• 由来する生物種: ELEPHANTULUS EDWARDII (CAPE LONG-EARED ELEPHANT SHREW)
• 細胞内の位置: Cytoplasm (By similarity): Q28399
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 221359.59

構造登録者

Purkiss, A.G.,Van Montfort, R.,Wistow, G.,Slingsby, C. (登録日: 2002-12-15, 公開日: 2003-04-17, 最終更新日: 2023-12-13)

主引用文献

Bateman, O.A.,Purkiss, A.G.,Van Montfort, R.,Slingsby, C.,Graham, C.,Wistow, G.
Crystal Structure of Eta-Crystallin: Adaptation of a Class 1 Aldehyde Dehydrogenase for a New Role in the Eye Lens
Biochemistry, 42:4349-, 2003

PubMed Abstract: Eta-crystallin is a retinal dehydrogenase that has acquired a role as a structural protein in the eye lens of elephant shrews, members of an ancient order of mammals. While it retains some activity toward retinal, which is oxidized to retinoic acid, the protein has acquired a number of specific sequence changes that have presumably been selected to enhance the lens role. The crystal structure of eta-crystallin, in common with class 1 and 2 ALDHs, is a dimer of dimers. It has a better-defined NAD binding site than those of related mammalian ALDH1 enzymes with the cofactor bound in the "hydride transfer" position in all four monomers with small differences about the dimer dyads. Although the active site is well conserved, the substrate-binding site is larger in eta-crystallin, and there are some mutations to the substrate access tunnel that might affect binding or release of substrate and product. It is possible that eta-crystallin has lost flexibility to improve its role in the lens. Enhanced binding of cofactor could enable it to act as a UV/blue light filter in the lens, improving visual acuity. The structure not only gives a view of a "natural mutant" of ALDH1 illustrating the adaptive conflict that can arise in multifunctional proteins, but also provides a well-ordered NAD binding site structure for this class of enzymes with important roles in development and health.

PubMed: 12693930
DOI: 10.1021/BI027367W

実験手法

X-RAY DIFFRACTION (2.4 Å)