Jinn T. L., Chen Y. M., Lin C. Y.
Department of Botany, National Taiwan University, Taipei, Taiwan.
Plant Physiol. 1995 Jun;108(2):693-701. doi: 10.1104/pp.108.2.693.
Examination of an ammonium sulfate-enriched fraction (70-100% saturation) of heat-shock proteins (HSPs) by nondenaturing polyacrylamide gel electrophoresis revealed the presence of a high molecular mass complex (280 kD) in soybean (Glycine max) seedlings. This complex cross-reacted with antibodies raised against soybean class I low-molecular-mass (LMW) HSPs. Dissociation of the complex by denaturing polyacrylamide gel electrophoresis showed the complex to contain at least 15 polypeptides of the 15-to 18-kD class I LMW HSPs that could be detected by staining, radiolabeling, and western blotting. A similar LMW-HSP complex was observed in mung bean (Vigna radiata L.; 295 kD), in pea (Pisum sativum L.; 270 kD), and in rice (Oryza sativa L.; 310 kD). The complex was stable under high salt conditions (250 mM KCI), and the integrity was not affected by 1% Nonidet P-40 and 3 [mu]g/ML RNase treatment. The size of the isolated HSP complex in vitro was conserved to 55[deg]C; however, starting at 37.5[deg]C, it changed to higher molecular forms in the presence of soluble proteins. The isolated HSP complex was able to protect up to 75% of the soluble proteins from heat denaturation in vitro.
通过非变性聚丙烯酰胺凝胶电泳对热休克蛋白（HSPs）的硫酸铵富集级分（70 - 100%饱和度）进行检测，结果显示大豆（Glycine max）幼苗中存在一种高分子量复合物（280 kD）。该复合物与针对大豆I类低分子量（LMW）HSPs产生的抗体发生交叉反应。通过变性聚丙烯酰胺凝胶电泳使该复合物解离，结果表明该复合物包含至少15种15至18 kD的I类LMW HSPs多肽，这些多肽可通过染色、放射性标记和蛋白质印迹法检测到。在绿豆（Vigna radiata L.；295 kD）、豌豆（Pisum sativum L.；270 kD）和水稻（Oryza sativa L.；310 kD）中也观察到了类似的LMW - HSP复合物。该复合物在高盐条件（250 mM KCl）下稳定，其完整性不受1% Nonidet P - 40和3 μg/mL核糖核酸酶处理的影响。体外分离的HSP复合物大小在55℃时保持不变；然而，从37.5℃开始，在可溶性蛋白质存在的情况下，它会转变为更高分子量的形式。体外分离的HSP复合物能够保护高达75%的可溶性蛋白质免受热变性。
