Regini Justyn W, Ecroyd Heath, Meehan Sarah, Bremmell Kristen, Clarke Matthew J, Lammie Donna, Wess Tim, Carver John A
School of Optometry and Vision Sciences, Cardiff University, Cardiff, UK.
Mol Vis. 2010 Nov 18;16:2446-56.
The molecular chaperone αB-crystallin is found in high concentrations in the lens and is present in all major body tissues. Its structure and the mechanism by which it protects its target protein from aggregating and precipitating are not known.
Dynamic light scattering and X-ray solution scattering techniques were used to investigate structural features of the αB-crystallin oligomer when complexed with target proteins under mild stress conditions, i.e., reduction of α-lactalbumin at 37 °C and malate dehydrogenase when heated at 42 °C. In this investigation, the size, shape and particle distribution of the complexes were determined in real-time following the induction of stress.
Overall, it is observed that the mass distribution, hydrodynamic radius, and spherical shape of the αB-crystallin oligomer do not alter significantly when it complexes with its target protein.
The data are consistent with the target protein being located in the outer protein shell of the αB-crystallin oligomer where it is readily accessible for possible refolding via the action of other molecular chaperones.
分子伴侣αB-晶状体蛋白在晶状体中含量很高，且存在于所有主要身体组织中。其结构以及保护靶蛋白不发生聚集和沉淀的机制尚不清楚。
采用动态光散射和X射线溶液散射技术，研究在温和应激条件下，即37℃时α-乳白蛋白还原以及42℃加热苹果酸脱氢酶时，αB-晶状体蛋白寡聚体与靶蛋白复合时的结构特征。在本研究中，应激诱导后实时测定复合物的大小、形状和颗粒分布。
总体而言，观察到αB-晶状体蛋白寡聚体与靶蛋白复合时，其质量分布、流体动力学半径和球形形状没有明显改变。
这些数据与靶蛋白位于αB-晶状体蛋白寡聚体的外部蛋白壳中一致，在那里它可以通过其他分子伴侣的作用很容易地进行可能的重折叠。
