Studies on the structure and function of protein kinase PKN

为了了解PKN的生理功能，我们分析了PKN相关蛋白。1) pkn -相关蛋白的鉴定与表征利用酵母双杂交系统鉴定了pkn -相关蛋白。通过这种筛选，已经发现PKN与一些细胞骨架成分相关，如神经丝、静脉蛋白和a-肌动蛋白。此外，PKN与PCD17之间的相互作用已被证实。PCD17是一种在副肿瘤小脑退行性综合征患者血清和脑脊液中检测到的可被抗普氏细胞自身抗体识别的神经抗原，其一级结构提示其可能是转录因子。2)应激诱导PKN从细胞质向细胞核的易位研究了环境应激对培养细胞PKN亚细胞定位的影响。在非应激细胞中，PKN的免疫荧光主要存在于细胞质区。当这些细胞在高温下处理时，细胞质区PKN的免疫荧光呈时间依赖性降低，与细胞核内PKN的免疫荧光增加相关。上述结果提出了PKN在细胞骨架组织和核事件中都起重要作用的可能性。

To understand the physiological function of PKN,PKN-associated proteins were analyzed.1) Identification and characterization of PKN-associated proteinsPKN-assocaited proteins were identified by the yeast two-hybrid system. By this screening, it has been found that PKN asscoiates some cytoskeletal components such as neurofilament, vimentin, and a-actinin. Moreover, the interaction between PKN and PCD17 has been shown. PCD17 is a neural antigen, which is recognized by anti-Pukinje cell autoantibodies, detected in sera and cerebrospinal fluids of patients with paraneoplastic cerebellar degeneration syndrome, and it has been suggested to be transcriptional factor by the primary structure.2) Translocation of PKN from the cytosol to the nucleus induced by stressesEffects of environmental stresses on the subcellular location of PKN were investigated in the cultured cells. The immunoflueorescence of PKN resided prominently in the cytoplasmic region in non-stressed cells. When these cells were treated at the high degree of temperature, there was a time-dependent decrease of the immunofluorescence of PKN in the cytoplasmic region that correlated with an increase within the nucleus.These results described as above raise the possibilities that PKN has important roles both in the cytoskeletal organization and nuclear events.