小白鼠心肌核DNA片段中的基因表达的分子开关的研究

摘要

It is observed by in situ stain that LDH(1-5)…nNAD+ can probabl y enter the nucleopore and bind specifically with the gene that encodes itself. During the i n vitro expression, the dilution of heart nuclear DNA fragments could enhance th e expression activity of LDH/DNA*, the amount of expressed LDH(1-5) is in propo rtion to the amount of dissociable LDH(1-5) on the LDH/DNA*. With the int egrati on of the 14　C-Leu to the protein, it is also observed that the additio n of LDH (1-5)…nNAD+ may suppress the in vitro expression activity of LDH/DNA* and the decreased amount of expressed LDH(1-5) is in proportion to the amount of a dded L DH(1-5)…nNAD+. AFM observation shows that the regulation sequence at t he two e nds of the active genes may bind with such active factors as the proteins encode d by the genes themselves.%原位染色发现，LDH(1-5)…nNAD+(LDH：乳酸脱氢酶，NAD＋：氢化型辅酶I)可以 进入核孔，可能与自己编码基因特异结合。体外表达 实验中，稀释心肌DNA片段，促进LDH/DNA*表达LDH(1-5)， LDH (1-5)表达量与LDH/DNA*中可 解离的LDH(1-5)量呈正相关性。同位素14C标记Leu法测定加入LDH(1-5) …nNAD+可以抑制LD H/DNA*体外表达，LDH(1-5)表达抑制量与加入LDH(1-5)…nNAD+量呈正相 关性。AFM直接观察 到活性基因两头的调控序列可能结合自己编码的蛋白等活性因子。基因表达与调控的分子开 关主要是自己编码的蛋白等活性因子。展示了未来运用AFM和同位素标记法相结合研 究生物学反应的前景。