Cullen B R, Skalka A M, Ju G
Proc Natl Acad Sci U S A. 1983 May;80(10):2946-50. doi: 10.1073/pnas.80.10.2946.
A sensitive and quantitative biological assay has been utilized to measure the ability of the exogenous and endogenous avian retroviral long terminal repeats (LTR) to promote gene expression in avian cells. This assay has revealed that the exogenous virus RAV-2 LTR is approximately equal to 10-fold more active than the LTRs of endogenous viruses RAV-0, ev-1, and ev-2. The endogenous viral LTRs show approximately equal activity. Upstream flanking cellular or viral sequences have no significant modulating effect on gene expression in our assay. Unexpectedly, we have detected and localized an additional defect outside of the LTR in the 5' noncoding leader sequence of ev-1 that further decreases gene expression relative to RAV-0 by approximately equal to 10-fold.
一种灵敏且定量的生物学检测方法已被用于测定外源性和内源性禽逆转录病毒长末端重复序列(LTR)促进禽细胞中基因表达的能力。该检测方法表明,外源性病毒RAV-2 LTR的活性大约比内源性病毒RAV-0、ev-1和ev-2的LTR高10倍。内源性病毒LTR表现出大致相同的活性。在我们的检测中,上游侧翼细胞或病毒序列对基因表达没有显著的调节作用。出乎意料的是,我们在ev-1的5'非编码前导序列的LTR之外检测到并定位了另一个缺陷,相对于RAV-0,该缺陷进一步使基因表达降低了约10倍。