Maitra R, McCoy S, Ahmad N, Holland SM, Lane CH, Venkatesan S; International Conference on AIDS.

Int Conf AIDS. 1990 Jun 20-23; 6: 149 (abstract no. F.A.292).

Laboratory of Molecular Microbiology, National Institute of Allergy and Infections Diseases, Bethesda, MD USA

OBJECTIVE: To investigate the effects of HIV-1 Nef protein on the HIV-1 expression and LTR transcription. METHODS: 1) A series of Nef + Jurkat lymphoid, HeLa and 3T3 cell lines expressing HIV-1 Nef from the HIV-1 LTR or from a constitutive CMV promoter or an inducible MMTV LTR were constructed; 2) Nef cell lines were selected by neomycin resistance; 3) plasmids containing Nef ORF in the anti-sense orientation or carrying a frame-shift termination served as negative controls; 3) virus production from a Nef+ and Nef- provirus was evaluated by DNA transfection of individual cell lines; 4) virus infectibility of individual clones was monitored using either viruses derived from cloned proviruses or sequential isolates from AIDS patients; 5) LTR transcription was evaluated by using CAT expression plasmids linked to wt or deletion mutants of HIV-1 LTR. RESULTS: Nef+ Jurkat cell lines were at least five-fold less efficient than Nef- counterparts in transient production of virus from several proviruses. Provirus expression was also repressed in the Nef+ HeLa cell lines. Replication of HIV-1 strains derived from cloned proviruses and sequential virus isolates from AIDS patients was also severely restricted. Virus production was delayed by 10-15 days and the magnitude of virus titers was only about 20% of the Nef- controls. Transcription from a complete HIV-1 LTR was repressed 5-10 fold in the Nef+ cell lines, whereas transcription from an LTR lacking NRE was not affected. CONCLUSION: Nef expressing cell lines down regulate HIV-1 replication, provirus expression and HIV-1 LTR transcription.

Publication Types:

• Meeting Abstracts

Keywords:

• Animals
• Cats
• Cell Line
• DNA Replication
• Down-Regulation
• Gene Expression
• Gene Expression Regulation, Viral
• Gene Products, nef
• HIV Long Terminal Repeat
• HIV-1
• Hela Cells
• Humans
• Mammary Tumor Virus, Mouse
• Promoter Regions (Genetics)
• Proviruses
• Terminal Repeat Sequences
• Transcription, Genetic
• Transfection
• genetics
• reverse transcriptase, Human immunodeficiency virus 1

Other ID:

• 20029290

UI: 102184194

From Meeting Abstracts