Zhang P, Hogan E L, Bhat N R
Department of Neurology, Medical University of South Carolina, Charleston 29425, USA.
Neurochem Res. 1998 Feb;23(2):219-25. doi: 10.1023/a:1022489127107.
Recently, we reported on the activation of c-Jun N-terminal kinase (JNK) in primary glial cells noting certain differences in the patterns of kinase activation in astrocytes and oligodendrocytes (Zhang et al., J Neurosci Res 46:114-121;1996). In this extended study, we have examined the activation and expression levels of JNK1 and JNK2 isoforms in different glial cell types including the two in vitro-defined astroglial subtypes (type-1 and type-2), oligodendrocytes and microglia. An in-gel kinase assay of cell extracts and JNK-immunoprecipitates revealed the activation of both JNK1 and JNK2 in type-1 astrocytes in response to TNFalpha, and in microglia, in response to TNFalpha and bacterial lipopolysaccharide. The strong activation of the two JNK isoforms in type-1 astrocytes and microglia contrasted with a predominant activation of JNK1 over JNK2 in type-2 astrocytes and oligodendrocytes, the two glial subtypes sharing a common lineage. Immunoblot and immunocytochemical analyses using isoform-specific antibodies showed a differential expression of the two isoforms in different glial cells thereby accounting for their observed differential activation.
最近，我们报道了原代神经胶质细胞中c-Jun氨基末端激酶（JNK）的激活情况，注意到星形胶质细胞和少突胶质细胞中激酶激活模式存在某些差异（Zhang等人，《神经科学研究杂志》46:114 - 121；1996年）。在这项扩展研究中，我们检测了不同神经胶质细胞类型中JNK1和JNK2亚型的激活和表达水平，这些细胞类型包括两种体外定义的星形胶质细胞亚型（1型和2型）、少突胶质细胞和小胶质细胞。对细胞提取物和JNK免疫沉淀物进行凝胶内激酶分析显示，1型星形胶质细胞中JNK1和JNK2均对TNFα有反应而被激活，小胶质细胞中JNK1和JNK2对TNFα和细菌脂多糖有反应而被激活。1型星形胶质细胞和小胶质细胞中两种JNK亚型的强烈激活与2型星形胶质细胞和少突胶质细胞中JNK1比JNK2的优势激活形成对比，这两种神经胶质细胞亚型具有共同的谱系。使用亚型特异性抗体进行的免疫印迹和免疫细胞化学分析显示，两种亚型在不同神经胶质细胞中的表达存在差异，从而解释了观察到的它们激活的差异。
