Masumi A, Aoi S, Shiga J, Tsukada K
Department of Pathological Biochemistry, Medical Research Institute, Tokyo Medical and Dental University, Japan.
Biochim Biophys Acta. 1990 Apr 9;1052(1):71-7. doi: 10.1016/0167-4889(90)90059-m.
Infusing a methionine-free solution into rats for 7 days resulted in a marked enlargement of liver nucleoli. By the analysis of two-dimensional gel electrophoresis, a spot 'a' (76 kDa, pI 5.3) stained with Coomassie blue was observed to accumulate highly in liver cytosol from rat infused with methionine-free solution. Metabolically labeling experiments with [35S]methionine showed that 'a' was more heavily labeled in primary hepatocytes of rats infused with methionine-free solution than in those of control rat. To ascertain whether 'a' is one of stress proteins, primary hepatocyte cultures were incubated at 42 degrees C for 2 h. 'a' (76 kDa, pI 5.3) was slightly induced in control hepatocytes but not appreciably in hepatocytes from the treated rat. In contrast, two other spots 'b' (74 kDa, pI 5.6) and 'c' (74 kDa, pI 5.3) were highly induced at 42 degrees C in hepatocytes from control and treated rats. The antibody against the consensus sequence peptide of hsp70 family reacted with 'a' (76 kDa, pI 5.3) as well as 'b' and 'c'. Immunoblot analysis revealed that 'a' accumulates highly in hepatocytes of treated rats. These results indicate that infusion of methionine-free solution into rats induces one member of the hsp70 family in hepatocytes.
给大鼠输注不含蛋氨酸的溶液7天会导致肝脏核仁明显增大。通过二维凝胶电泳分析，观察到一个用考马斯亮蓝染色的斑点“a”（76 kDa，pI 5.3）在输注不含蛋氨酸溶液的大鼠肝脏细胞质中高度积累。用[35S]蛋氨酸进行的代谢标记实验表明，在输注不含蛋氨酸溶液的大鼠原代肝细胞中，“a”的标记程度比对照大鼠的原代肝细胞更高。为了确定“a”是否是应激蛋白之一，将原代肝细胞培养物在42℃孵育2小时。对照肝细胞中“a”（76 kDa，pI 5.3）略有诱导，但在处理过的大鼠的肝细胞中诱导不明显。相比之下，另外两个斑点“b”（74 kDa，pI 5.6）和“c”（74 kDa，pI 5.3）在对照和处理过的大鼠的肝细胞中于42℃时被高度诱导。针对hsp70家族共有序列肽的抗体与“a”（76 kDa，pI 5.3）以及“b”和“c”发生反应。免疫印迹分析显示“a”在处理过的大鼠的肝细胞中高度积累。这些结果表明，给大鼠输注不含蛋氨酸的溶液会在肝细胞中诱导hsp70家族的一个成员。
