title: Sequence insertions in the HIV type 1 subtype C viral promoter predominantly generate an additional NF-κB binding site.
abstract: After screening a large number of clinical samples of HIV-1 subtype C in India, a subset of viral strains containing sequence insertions upstream of the viral enhancer has been identified. The sequence insertions contained binding sites for at least two different transcription factors NF-κB and RBEIII, importantly, in a mutually exclusive fashion. Furthermore, while some of the viral strains contained insertions of κB-like sites, a few others contained dual insertions of the RBEIII and κB sites together but only one of the two was intact. NF-κB acquisition appears to be the most common phenotype unique for subtype C with nearly half of the variant strains containing such insertions. Given that subtype C already contains three functional NF-κB sites in the viral enhancer, acquisition of a fourth NF-κB motif in some variant viral strains is intriguing. Further investigation is warranted to examine the significance of the sequence insertions for the replicative fitness of the variant viral strains.
authors.affiliation: HIV-AIDS Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, India.
authors.forename: Mahesh
authors.initials: M
authors.lastname: Bachu
authors.forename: Anil Babu
authors.initials: AB
authors.lastname: Mukthey
authors.forename: Rajesh V
authors.initials: RV
authors.lastname: Murali
authors.forename: Narayanaiah
authors.initials: N
authors.lastname: Cheedarla
authors.forename: Anita
authors.initials: A
authors.lastname: Mahadevan
authors.forename: Susarla K
authors.initials: SK
authors.lastname: Shankar
authors.forename: Kadappa S
authors.initials: KS
authors.lastname: Satish
authors.forename: Tapas K
authors.initials: TK
authors.lastname: Kundu
authors.forename: Udaykumar
authors.initials: U
authors.lastname: Ranga
mesh_terms: D000328:Adult; D001665:Binding Sites / Q000235:genetics; D019143:Evolution, Molecular; D005260:Female; D014644:Genetic Variation; D006679:HIV Seropositivity / Q000453:epidemiology / Q000276:immunology / Q000821:virology*; D015497:HIV-1 / Q000235:genetics*; D006801:Humans; D007194:India / Q000453:epidemiology; D008297:Male; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional / Q000235:genetics*; D016328:NF-kappa B / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics*; D014779:Virus Replication
chemical_list: D016328:NF-kappa B