POST-TRANSCRIPTIONAL REGULATOR (REX) OF HTLV-1 INITIATES EXPRESSION OF VIRAL STRUCTURAL PROTEINS BUT SUPPRESSES EXPRESSION OF REGULATORY PROTEINS
POST-TRANSCRIPTIONAL REGULATOR (REX) OF HTLV-1 INITIATES EXPRESSION OF VIRAL STRUCTURAL PROTEINS BUT SUPPRESSES EXPRESSION OF REGULATORY PROTEINS
复制标题
DOI：
10.1002/j.1460-2075.1988.tb02840.x
复制
发表时间：
1988-02-01
期刊：
影响因子：
11.4
通讯作者：
SEIKI, M
中科院分区：
文献类型：
--
作者：
HIDAKA, M;INOUE, J;SEIKI, M
人T细胞白血病病毒1型（HTLV-1）的基因表达受pX区编码的两个反式作用因子p40 tax和p27 rex的调控。p40 tax是转录激活因子，p27 rex是转录后调节因子。利用全长病毒DNA研究了雷克斯对HTLV-1基因表达的调控作用。p27 rex是gag和env蛋白表达所必需的，增加了它们的mRNA水平。p27 rex表达质粒的剂量依赖于p27 rex表达质粒的剂量。与此同时，增加剂量的p27 rex抑制了完全剪接的pX mRNA的表达，该mRNA编码调节蛋白。p27 rex的这两种作用均在转录后水平起作用，不受转录调控的影响。降低pX mRNA的水平并不调节前病毒基因组的转录。这些观察结果表明，雷克斯是一个积极的转录后调节gag，pol和env蛋白的表达，并在同一时间作为一个间接的负调节病毒转录。
Gene expression of human T-cell leukemia virus type 1 (HTLV-1) is regulated by two trans-acting factors encoded by the pX region, p40tax and p27rex. p40tax is a transcriptional activator and p27rex is a post-transcriptional regulator. Using full-length viral DNA, we studied the regulatory effects of rex on HTLV-1 gene expression. p27rex is required for expression of both gag and env proteins, increasing the level of their mRNAs. The effect was dependent on the dose of p27rex expression plasmid. In parallel, increased doses of p27rex suppressed the expression of fully spliced pX mRNA, which encodes the regulatory proteins. These two effects of p27rex operated at the post-transcriptional level and were independent of transcriptional regulation. Lowering the level of pX mRNA doen-regulates transcription of the proviral genome. These observations demonstrate that rex is a positive post-transcriptional regulator for gag, pol and env protein expression, and acts at the same time as an indirect negative regulator of viral transcription.