NAG7基因转染HNE1细胞后下调蛋白质的鉴定及其意义(英文)

NAG7基因是我室克隆的与鼻咽癌相关的肿瘤抑制候选基因 .将NAG7编码框的cDNA片段克隆至pGEM3.1(+ )的表达载体 ,经脂质体转染入HNE1细胞 ,经G4 18筛选 ,并运用PCR技术证实 .建立含NAG7基因稳定转染的细胞系 ,抽提细胞总蛋白质 ,双向凝胶电泳分离蛋白质 ,对表达下调的蛋白质点进行质谱分析 ,获得的肽质指纹经SWISS PROT数据库分析以鉴定蛋白质点 .鉴定出的 7个下调蛋白质包括纤溶酶原、收缩蛋白、Ras 相关蛋白Rab 36及ARF 相关蛋白等 .通过对蛋白质性质和功能的分析 ,发现这些蛋白质参与了细胞信号的转导、蛋白质的转运及细胞代谢等众多事件 .因此 ,NAG7基因很可能是通过介导这些蛋白质的表达下调而发挥其功能

Identification and Significance of Down-regulated Proteins in HNE1 Cells Transfected with NAG7

To investigate the function of NAG 7 gene, proteomic methods were used to find and identify the down regulated proteins, and expected to elucidate the mechanism of NAG7. NAG7 , a novel putative tumor suppressor gene, was introduced into HNE1 cells by liposome transfection. Two dimensional polyacrylamide gel electrophoresis (2 D PAGE) was used to gain the protein expression pattern of transfected cells. Down regulated proteins were identified by mass spectrometry (MS). The NAG 7 eukaryotic expression vector was constructed and transfected into HNE1. Resistant clones were obtained after G418 selection, and positive clones were confirmed by PCR. Seven down regulated proteins were identified from mass spectrometric peptide fingerprints. These proteins involved in cell metabolism, signaling transduction pathway, protein transport and supplied the nucleotide substrate for thymidylate synthetase. The functions of NAG 7 may be partially mediated by these down regulated proteins.