HTLV-III SEQUENCES AT THE TRANSCRIPTIONAL LEVEL

转录水平的 HTLV-III 序列

基本信息

批准号：
3453899
负责人：
Joseph D Mosca
金额：
$ 8.4万
依托单位：
HENRY M. JACKSON FDN FOR THE ADV MIL/MED
依托单位国家：
美国
项目类别：
财政年份：
1989
资助国家：
美国
起止时间：
1989-09-30 至 1993-04-30
项目状态：
已结题

项目摘要

Opportunistic viral infections are prevalent in patients with acquired immune deficiency syndrome (AIDS). To investigate the possibility that opportunistic infections in the herpesvirus group might induce expression from the human T-lymphotropic virus type III (HTLV-III) long-terminal repeats (LTR), we constructed permanent cell lines (murine and simian), containing the HTLV-III LTR directing the chloramphenicol acetyltransferase (CAT) gene. Whereas in transient gene expression assays, the HTLV-III LTR express CAT activity as high as the simian virus-40 (SV40) early promoter, no CAT activity is observed after chromatin integration in permanent cell lines. Superinfection of these latent HTLV-III LTR containing lines with herpes viruses reactivated the HTLV-III LTR as determined by S1 nuclease RNA analysis. Whereas simian virus-40 (SV40) and adenovirus infection of the latent HTLV-III LTR containing cell lines did not activate HTLV- III LTR expression. Reactivation of latent HTLV-III LTR transcription is also observed after 5 azacytidine, cycloheximide and UV irradiation treatments. Run-on transcription in isolated nuclei, suggests that the activation is on the transcriptional level. Activation by herpes simplex virus type 1 (HSV-1) required viral immediate early (IE) gene expression as determined by virus infection in the presence of cycloheximide and with mutants defective in viral gene expression. The long-term objective of the research described in this proposal is to elucidate the mechanism(s) by which the HTLV-III LTR could be activated on the transcriptional level. The specific aims are to identify the viral gene products responsible for latent HTLV-III LTR transcription activation; to establish permanent cell lines in human B and T-cells containing the HTLV-III LTR; to identify the mechanism(s) of repression of the HTLV-III regulatory region and to define the HTLV-III LTR DNA sequences involved repression and reactivation. The preliminary results suggest that opportunistic infection of the herpesvirus group could induce HTLV-III expression in individuals harboring the virus in a latent form and points to the potential of these cell lines to study the affects of other physiochemical stimuli on HTLV-III reactivation.

机会性病毒感染普遍存在获得的免疫缺陷综合征（AIDS）。调查疱疹病毒组的机会性感染的可能性可能诱导人类T淋巴病毒的表达 III型（HTLV-III）长末端重复序列（LTR），我们构建了永久性细胞系（鼠和猿猴），包含HTLV-III LTR指导氯霉素乙酰转移酶（CAT）基因。而在瞬态基因表达测定中，HTLV-III LTR 早期的表达CAT活性与Simian Virus-40（SV40）一样高启动子，染色质后未观察到CAT活性在永久性细胞系中积分。这些潜在的超级感染 HTLV-III LTR含有疱疹病毒的线条重新激活通过S1核酸酶RNA分析确定的HTLV-III LTR。而Simian病毒-40（SV40）和腺病毒感染潜在的HTLV-III LTR含有细胞系没有激活HTLV- III LTR表达。潜在的HTLV-III LTR重新激活在5个azacytidine，Cycloheximide之后也观察到转录和紫外线照射治疗。孤立的运行转录细胞核表明激活在转录水平上。通过单纯疱疹病毒1型（HSV-1）激活所需病毒由病毒确定的立即早期（IE）基因表达在存在环己酰亚胺和突变体的情况下感染病毒基因表达有缺陷。长期目标该提案中描述的研究是阐明 HTLV-III LTR可以激活的机制转录级别。具体目的是确定负责潜在HTLV-III LTR的病毒基因产品转录激活；在包含HTLV-III LTR的人B和T细胞；识别 HTLV-III监管区域和抑制的机制定义HTLV-III LTR DNA序列涉及抑制和重新激活。初步结果表明疱疹病毒组的机会性感染可能引起在潜在病毒的个体中的HTLV-III表达形式并指出了这些细胞系的潜力其他生理化学刺激对HTLV-III重新激活的影响。