Haass C, Kloetzel P M
ZMBH/Molekulare Genetik Universität Heidelberg, F.R.G.
Biochem Biophys Res Commun. 1990 Apr 16;168(1):314-9. doi: 10.1016/0006-291x(90)91710-a.
The molecular organization of alpha ecdysone induced small heat shock proteins (small hsps) in Schneider's S3 tissue culture cells was analysed. Sucrose gradient centrifugation of cytoplasmic extracts and nondenaturing gel electrophoresis shows that hormone induced small hsps form 16S particles which differ in the relative molar ratios of the small hsps composing the 16S particles. The 16S particles possess a buoyant density in Cs2SO4 of rho = 1.34 g/cm3 which is indicative of RNP complexes with an RNA:protein ratio of 1:4. The RNA component of the 16S particles was identified by cDNA cloning using a cDNA library established from alpha ecdysone induced pupal 16S material. Northern hybridization using the 16S RNP specific partial cDNA clone Ec3 identifies a single alpha ecdysone inducible 300 nt RNA species. Our data suggest that the small hsps may unfold their so far unresolved function in form of RNP complexes.
对α-蜕皮激素诱导的施耐德S3组织培养细胞中的小热休克蛋白（小hsps）的分子组织进行了分析。对细胞质提取物进行蔗糖梯度离心和非变性凝胶电泳表明，激素诱导的小hsps形成16S颗粒，组成16S颗粒的小hsps的相对摩尔比不同。16S颗粒在Cs2SO4中的浮力密度为ρ = 1.34 g/cm3，这表明其为RNA：蛋白质比率为1:4的核糖核蛋白复合物。使用从α-蜕皮激素诱导的蛹16S材料建立的cDNA文库，通过cDNA克隆鉴定了16S颗粒的RNA成分。使用16S核糖核蛋白特异性部分cDNA克隆Ec3进行的Northern杂交鉴定出一种单一的α-蜕皮激素诱导的300 nt RNA物种。我们的数据表明，小hsps可能以核糖核蛋白复合物的形式发挥其迄今尚未明确的功能。
