ジャーナル: Nat Struct Mol Biol / 年: 2019 タイトル: The structure and oxidation of the eye lens chaperone αA-crystallin. 著者: Christoph J O Kaiser / Carsten Peters / Philipp W N Schmid / Maria Stavropoulou / Juan Zou / Vinay Dahiya / Evgeny V Mymrikov / Beate Rockel / Sam Asami / Martin Haslbeck / Juri Rappsilber / ...著者: Christoph J O Kaiser / Carsten Peters / Philipp W N Schmid / Maria Stavropoulou / Juan Zou / Vinay Dahiya / Evgeny V Mymrikov / Beate Rockel / Sam Asami / Martin Haslbeck / Juri Rappsilber / Bernd Reif / Martin Zacharias / Johannes Buchner / Sevil Weinkauf / 要旨: The small heat shock protein αA-crystallin is a molecular chaperone important for the optical properties of the vertebrate eye lens. It forms heterogeneous oligomeric ensembles. We determined the ...The small heat shock protein αA-crystallin is a molecular chaperone important for the optical properties of the vertebrate eye lens. It forms heterogeneous oligomeric ensembles. We determined the structures of human αA-crystallin oligomers by combining cryo-electron microscopy, cross-linking/mass spectrometry, NMR spectroscopy and molecular modeling. The different oligomers can be interconverted by the addition or subtraction of tetramers, leading to mainly 12-, 16- and 20-meric assemblies in which interactions between N-terminal regions are important. Cross-dimer domain-swapping of the C-terminal region is a determinant of αA-crystallin heterogeneity. Human αA-crystallin contains two cysteines, which can form an intramolecular disulfide in vivo. Oxidation in vitro requires conformational changes and oligomer dissociation. The oxidized oligomers, which are larger than reduced αA-crystallin and destabilized against unfolding, are active chaperones and can transfer the disulfide to destabilized substrate proteins. The insight into the structure and function of αA-crystallin provides a basis for understanding its role in the eye lens.
ダウンロード / ファイル: emd_4896.map.gz / 形式: CCP4 / 大きさ: 8 MB / タイプ: IMAGE STORED AS FLOATING POINT NUMBER (4 BYTES)
注釈
Single particle cryo-EM reconstruction of a 20-mer assembly of reduced recombinant human alphaA-crystallin.
ボクセルのサイズ
X=Y=Z: 1.35 Å
密度
表面レベル
登録者による: 0.0119 / ムービー #1: 0.0119
最小 - 最大
-0.00000001640 - 0.124002606
平均 (標準偏差)
0.0041572717 (±0.014406236)
対称性
空間群: 1
詳細
EMDB XML:
マップ形状
Axis order
X
Y
Z
Origin
0
0
0
サイズ
128
128
128
Spacing
128
128
128
セル
A=B=C: 172.8 Å α=β=γ: 90.0 °
CCP4マップ ヘッダ情報:
mode
Image stored as Reals
Å/pix. X/Y/Z
1.35
1.35
1.35
M x/y/z
128
128
128
origin x/y/z
0.000
0.000
0.000
length x/y/z
172.800
172.800
172.800
α/β/γ
90.000
90.000
90.000
MAP C/R/S
1
2
3
start NC/NR/NS
0
0
0
NC/NR/NS
128
128
128
D min/max/mean
-0.000
0.124
0.004
-
添付データ
-
試料の構成要素
-
全体 : Reduced recombinant human alphaA-crystallin
全体
名称: Reduced recombinant human alphaA-crystallin
要素
複合体: Reduced recombinant human alphaA-crystallin
タンパク質・ペプチド: alphaA-crystallin
-
超分子 #1: Reduced recombinant human alphaA-crystallin
超分子
名称: Reduced recombinant human alphaA-crystallin / タイプ: complex / ID: 1 / 親要素: 0 / 含まれる分子: all 詳細: Recombinant wild type full-length human alphaA-crystallin purified in the presence of reductant.
凍結剤: ETHANE / チャンバー内温度: 293 K / 装置: HOMEMADE PLUNGER 詳細: Diluted equilibrated specimen was added to glow-discharged (30s) grids. Sample was blotted 30s after sample application and immediately plunged..
詳細
Specimen was thawed, diluted to the final concentration and equilibrated at 310K for 3h.