Dillmann W H, Barrieux A, Reese G S
J Biol Chem. 1984 Feb 25;259(4):2035-8.
Rat cardiac ventricular myosins and RNA were prepared from normal, diabetic, insulin-treated diabetic, hypothyroid, and 3,3',5-triiodo-L-thyronine-treated hypothyroid rats. Myosin heavy chains isolated from purified myosin or synthesized in vitro from cardiac RNAs were subjected to partial protease digestion during sodium dodecyl sulfate-polyacrylamide gel electrophoresis. It was found that peptide maps obtained from cardiac myosin heavy chains of hypothyroid and diabetic rats were identical but differed from the maps of myosin heavy chain from control and hormone-treated animals. The same results were obtained, whether the heavy chains were isolated from purified myosin synthesized in the intact heart or from translation products coded for by cardiac RNAs added to the modified reticulocyte lysate. These results indicate that the myosin heavy chain RNA species present in the hypothyroid heart is also expressed during insulin deficiency but differs from the species expressed in normal animals. The expression of the two myosin heavy chain RNA species found in the rat cardiac ventricle appears to be independently regulated by these two hormones.
从正常大鼠、糖尿病大鼠、胰岛素治疗的糖尿病大鼠、甲状腺功能减退大鼠以及三碘甲状腺原氨酸治疗的甲状腺功能减退大鼠中制备大鼠心脏心室肌球蛋白和RNA。从纯化的肌球蛋白中分离或从心脏RNA体外合成的肌球蛋白重链，在十二烷基硫酸钠-聚丙烯酰胺凝胶电泳过程中进行部分蛋白酶消化。结果发现，甲状腺功能减退大鼠和糖尿病大鼠心脏肌球蛋白重链的肽图相同，但与对照动物和激素治疗动物的肌球蛋白重链图谱不同。无论重链是从完整心脏中合成的纯化肌球蛋白中分离出来，还是从添加到改良网织红细胞裂解物中的心脏RNA编码的翻译产物中分离出来，都得到了相同的结果。这些结果表明，甲状腺功能减退心脏中存在的肌球蛋白重链RNA种类在胰岛素缺乏时也会表达，但与正常动物中表达的种类不同。大鼠心脏心室中发现的两种肌球蛋白重链RNA种类的表达似乎受这两种激素的独立调节。
