Analysis of human papillomavirus type 16 late mRNA 3' processing signals in vitro and in vivo
Analysis of human papillomavirus type 16 late mRNA 3' processing signals in vitro and in vivo
复制标题
人乳头瘤病毒 16 型晚期 mRNA 3 体外和体内加工信号分析
作者：
I. Kennedy;J. Haddow;J. Clements
在人乳头瘤病毒16型基因组中，三个晚期mRNA推定的3'加工信号，命名为LP 1、LP 2和LP 3，位于晚期编码区的下游。我们的研究结果表明，在体外和体内，在HeLa细胞中，LP 2信号功能。因此，在HeLa细胞和其他未分化上皮细胞中观察到的人乳头瘤病毒16型晚期基因表达的限制不是通过调节晚期mRNA poly（A）位点的使用来实现的。有趣的是，在富含GU的下游序列元件中的三个核苷酸的改变将非功能性LP 1转化为有效的3'加工位点，表明LP 1可能在HeLa以外的细胞类型中起作用，例如分化的角质形成细胞。我们的转染研究已经确定了位于晚期mRNA 3'加工信号上游的负调控元件;该元件与3'加工中的任何改变无关，并且可能充当mRNA不稳定元件。
In the human papillomavirus type 16 genome, three late mRNA putative 3' processing signals, designated LP1, LP2, and LP3, are located downstream of the late coding region. Our results show, both in vitro and in vivo, that in HeLa cells, the LP2 signal functions. Thus, the restriction in human papillomavirus type 16 late-gene expression observed in HeLa cells and other nondifferentiated epithelial cells is not achieved by regulation of late mRNA poly(A) site usage. Interestingly, alteration of three nucleotides in the GU-rich downstream sequence element converts the nonfunctional LP1 to an efficient 3' processing site, suggesting that LP1 may function in cell types other than HeLa, such as differentiated keratinocytes. Our transfection studies have identified a negative regulatory element located immediately upstream of the late mRNA 3' processing signals; this element was not associated with any alteration in 3' processing and may act as an mRNA instability element.