Human papillomavirus type 16 E5 protein colocalizes with the antiapoptotic Bcl-2 protein
Human papillomavirus type 16 E5 protein colocalizes with the antiapoptotic Bcl-2 protein
复制标题
DOI：
10.1007/s00705-004-0325-8
复制
发表时间：
2004-09-01
影响因子：
2.7
通讯作者：
Auvinen, P
中科院分区：
文献类型：
--
作者：
Auvinen, E;Alonso, A;Auvinen, P
人乳头瘤病毒16型E5蛋白通过增加生长因子受体对细胞核的有丝分裂刺激而促进细胞转化。为了研究E5蛋白的生物学机制，我们对E5基因进行了定点突变。在人宫颈上皮细胞中瞬时表达野生型和突变型E5蛋白，并对细胞形态、细胞黏附相关蛋白的表达以及不同蛋白的定位进行了研究。不同的E5蛋白在细胞形态或表达动力学上几乎没有差异，除了一个突变的E5蛋白的重新定位，其中疏水的亮氨酸膜锚定突变为带正电的氨基酸。该突变的E5蛋白定位于片状脂体，片状脂体是位于运动细胞前沿的运动相关结构。在我们的实验条件下，表达E5的上皮细胞在表达4天后100%死亡，可能是由于E5蛋白对细胞膜的毒性或干扰。最有趣的是，E5蛋白和Bcl2抗凋亡蛋白在细胞内膜上显著地共存。
Human papillomavirus type 16 E5 protein contributes to cellular transformation by increasing the mitogenic stimulus from growth factor receptors to the nucleus. In order to study the biological mechanisms of the E5 protein we performed site-directed mutagenesis of the E5 gene. Wild-type as well as mutant E5 proteins were transiently expressed in human cervical epithelial cells, and cell morphology, expression of proteins involved in cell adhesion, and localization of the different proteins were studied. Little differences in cell morphology or expression kinetics were observed between the different E5 proteins, except for relocalization of a mutant E5 protein where a hydrophobic leucine membrane anchor was mutated to positively charged amino acids. This mutant E5 protein localized to lamellipodia, which are motility-associated structures at the leading edge of motile cells. In our experimental conditions, 100% of E5-expressing epithelial cells died by four days of expression, possibly due to toxicity or disturbance of the membrane compartment by the E5 protein. Most interestingly, a remarkable colocalization of the E5 protein with the Bcl-2 antiapoptotic protein on intracellular membranes was established.