Hunt D M, Wake S A, Mercer J F, Danks D M
Biochem J. 1986 Jun 1;236(2):409-15. doi: 10.1042/bj2360409.
The role of metallothionein (MT) was assessed in the copper-loading disease prevalent in Bedlington terriers. Fractionation of tissue supernatants over Sephadex G-75 showed that most of the additional cytosolic copper present in liver tissue of these dogs was bound to MT, and that substantially more MT-bound copper could be solubilized by detergent plus mercaptoethanol. Zinc contents were only slightly raised, although most of the extra zinc was associated with a 4000-Mr ligand. Ion-exchange chromatography revealed two isoproteins, MT1 and MT2, in all the dog liver samples examined. In Bedlington terrier liver, copper associated with both isoproteins was increased, although the increase for MT2 was greater than for MT1. The content of MT protein was also raised, although cell-free translations and RNA blots of total liver RNA showed that this increase was not associated with a rise in MT mRNA. The significance of these results to the mechanism of copper accumulation in the Bedlington terrier disorder is discussed.
对金属硫蛋白（MT）在贝德灵顿梗犬中普遍存在的铜蓄积病中的作用进行了评估。通过Sephadex G - 75对组织上清液进行分级分离表明，这些犬肝脏组织中额外的大部分胞质铜与MT结合，并且去污剂加巯基乙醇能够溶解更多与MT结合的铜。锌含量仅略有升高，尽管大部分额外的锌与一种4000道尔顿的配体相关。离子交换色谱法在所有检测的犬肝脏样本中均显示出两种同工蛋白，即MT1和MT2。在贝德灵顿梗犬肝脏中，与这两种同工蛋白结合的铜均增加，尽管MT2的增加幅度大于MT1。MT蛋白的含量也有所升高，尽管无细胞翻译和肝脏总RNA的RNA印迹显示这种增加与MT mRNA的升高无关。讨论了这些结果对贝德灵顿梗犬疾病中铜蓄积机制的意义。
