Hepburne-Scott H W, Crabbe M J
Division of Cell and Molecular Biology, School of Animal and Microbial Sciences, The University of Reading, Whiteknights, Reading, Berkshire, UK.
Mol Vis. 1999 Aug 10;5:15.
To understand the relationship between certain conserved residues in alphaB crystallin and the chaperone-like function of the protein.
In alphaB crystallin, residues H101 to R120 are highly conserved between alphaB crystallin and alphaA crystallin (85% identity), and between alphaB crystallin and the small heat shock protein hsp 27 (80% identity). We made three substitution mutants of alphaB crystallin: the single mutant F118A, and the double mutants K103L/H104I, and E110H/H111E.
Polyacrylamide gel electrophoresis revealed no decrease in aggregate size or measureable structural changes between them and the native structure. Using the insulin aggregation assay, all three mutants had identical chaperone-like activity to the wild-type recombinant alphaB crystallin.
Despite the high conservation in this area of sequence between alphaB crystallin, alphaA crystallin, and the small heat shock protein hsp 27, mutations F118A, K103L/H104I, and E110H/H111E did not significantly alter chaperone-like activity.
了解αB晶状体蛋白中某些保守残基与该蛋白伴侣样功能之间的关系。
在αB晶状体蛋白中，H101至R120残基在αB晶状体蛋白与αA晶状体蛋白之间（同一性为85%）以及αB晶状体蛋白与小热休克蛋白hsp 27之间（同一性为80%）高度保守。我们构建了αB晶状体蛋白的三个替代突变体：单突变体F118A以及双突变体K103L/H104I和E110H/H111E。
聚丙烯酰胺凝胶电泳显示，它们与天然结构相比，聚集体大小没有减小，也没有可测量的结构变化。使用胰岛素聚集试验，所有三个突变体与野生型重组αB晶状体蛋白具有相同的伴侣样活性。
尽管αB晶状体蛋白、αA晶状体蛋白和小热休克蛋白hsp 27在该序列区域高度保守，但F118A、K103L/H104I和E110H/H111E突变并未显著改变伴侣样活性。
