表达豇豆胰蛋白酶抑制剂转基因杨树的蛋白检测

对转豇豆胰蛋白酶抑制剂基因的三倍体毛白杨杂种 (毛新杨×毛白杨 )×毛白杨 ]的可溶性总蛋白和胰蛋白酶抑制剂蛋白的含量进行测定 .结果发现 ,与未转基因植株相比 ,所有供试转基因株系叶片中的总可溶性蛋白含量明显增加 ,但老叶的含量高于嫩叶 ,这表明转基因株系可溶性总蛋白含量增加可能是CpTI基因表达的结果或由于外源基因导入后引起杨树基因组中某些自身基因的表达所致 .转基因株系叶片中有较高含量CpTI,而对照叶片则检测不到CpTI,这进一步证实了CpTI基因已在转基因株系中得到稳定表达 .进一步比较发现 ,在供试的 5个无性系中 ,TG0 7、TG0 4和TG71在总蛋白含量和CpTI含量增加较为明显 .另外 ,聚丙烯酰胺凝胶电泳胶分析发现 ,与未转基因植株相比 ,在所有供试转基因株系叶片中均出现一条分子量为 11.3kD的清晰蛋白带

Identification of Expression of CpTI Gene in Transgenic Poplars at Protein Level

The contents of total soluble protein and cowpea trypsin inhibitor (CpTI) in the browse and metaphylla of transgenic hybrid triploid poplars ( Populus tomentosa × P. bolleana) × P. tomentosa ] transformed with CpTI gene were determined in order to study the products of CpTI gene expression at protein level. The results indicated that the amount of total soluble protein was greater in transgenic poplars than in non-transgenic poplars, but was more in the metaphylla than in browse. The expression of CpTI gene resulted in an obvious increase in CpTI content, whereas CpTI was not detected in non-transgenic poplars. It was found that there were high amount of total soluble protein and CpTI in 3 clones of TG07, TG04 and TG71 compared with other transgenic clones. In addition, the analysis of protein by SDS-PAGE showed that a specific protein band of about 11.3 kD corresponding to the 80 amino acids encoded by the CpTI gene was observed in transgenic poplars on the gel of protein, which was not detected in non-transgenic poplars.