- 作者: Stephane Emiliani; Nolwenn Coudronniere; Claude Delsert; Christian Devaux
- 作者服務機構: a Laboratoire dTmmunologie des Infections Retrovirales, CNRS UPR9008 et INSERM U249, Institut de Biologie, and; b UMR9947 IFREMER-CNRS, UMII, Montpellier, France
- 中文摘要: --
- 英文摘要: Sequencing of HIV-Iger long terminal repeat (LTR) has demonstrated, for the first time in an HIV-1 primary isolate, a TAR duplication refered to as TAR1 (nucleotides +1 through +68) and TAR2 (nucleotides +69 through +136). This TAR duplication is stable during replication of HIV-1 ger isolate in CEM cells. Analysis of LTR-CAT reporter constructs demonstrated that under Tat trans-activation the HIV-IGer/LTR (containing TAR1 and TAR2) was expressed at a higher level than a similar construct (HIV-Iger △TAR) containing a single TAR sequence. Among the two transcription initiation sites found in the HIV-Iger/LTR, only the most 5' start site was shown to be functionally active. The predicted secondary structure of the 5'-end mRNAs of HIV-Iger suggests it may fold into a double TAR hairpin which resembles that of HIV-2. Finally, HIV-Iger Tat protein shows primary sequence similarity with Tat proteins from other isolates of HIV-1 and is apparently unrelated to HIV-2 Tat proteins. This work provides the first evidence of a TAR sequence duplication in HIV-1 which increases the efficiency of transactivation by Tat.
- 中文關鍵字: --
- 英文關鍵字: HIV; Duplicated sequence ; Transcription