Gasull T, Hidalgo J
Department de Biologia Cellular i de Fisiologia, Facultat de Ciències, Universitat Autònoma de Barcelona, Bellaterra, Spain.
Neurochem Res. 1996 Aug;21(8):969-74. doi: 10.1007/BF02532348.
When brain extracts were fractionated in a Sephadex G-75 chromatography and MT levels were assayed by RIA or ELISA using polyclonal antibodies specific for the MT-I and MT-II isoforms, it was found that MT mostly eluted in the high molecular weight (HMW) peak even in reducing or anaerobic conditions. This was also the case for the liver extracts of control rats; in stressed animals MT immunoreactivity in the HMW peak (> 80 Kd) was increased compared with undisturbed animals, but the major amount of the newly induced MT eluted, as expected from the current literature, in the low molecular weight (LMW) peak, around 10 Kd. The addition of purified MT to brain extracts precluded its binding to a DEAE-Sephadex column. Furthermore, immunoblot results of native PAGE showed that MT changed its electrophoretic mobility in the presence of HMW proteins from brain cytosol. Altogether, these results suggest that a cytosolic factor binds MT in a saturable manner, which may have strong physiological implications.
当用葡聚糖凝胶G - 75柱色谱法对脑提取物进行分级分离，并使用针对MT - I和MT - II亚型的多克隆抗体通过放射免疫分析（RIA）或酶联免疫吸附测定（ELISA）来检测MT水平时，发现即使在还原或厌氧条件下，MT大多在高分子量（HMW）峰中洗脱。对照大鼠的肝脏提取物也是如此；与未受干扰的动物相比，应激动物中HMW峰（> 80 Kd）中的MT免疫反应性增加，但正如当前文献所预期的那样，新诱导的MT的主要部分在低分子量（LMW）峰（约10 Kd）中洗脱。向脑提取物中添加纯化的MT可阻止其与二乙氨基乙基葡聚糖（DEAE - Sephadex）柱结合。此外，天然聚丙烯酰胺凝胶电泳（native PAGE）的免疫印迹结果表明，在存在来自脑细胞质的HMW蛋白的情况下MT改变了其电泳迁移率。总之，这些结果表明一种胞质因子以可饱和的方式结合MT，这可能具有重要的生理意义。
