Ferraro Geraldo A, Monteiro-Cunha Joana P, Fernandes Flora M C, Mota-Miranda Aline C A, Brites Carlos, Alcantara Luiz C J, Galvão-Castro Bernardo, Morgado Mariza G
Laboratório Avançado de Saúde Pública (LASP), Centro de Pesquisa Gonçalo Moniz (CPqGM), Fundação Oswaldo Cruz (FIOCRUZ), Salvador, Bahia, Brazil.
AIDS Res Hum Retroviruses. 2013 May;29(5):837-41. doi: 10.1089/aid.2012.0326. Epub 2012 Dec 16.
HIV-1 provirus activation is under control of the long terminal repeat (LTR)-5' viral promoter region, which presents remarkable genetic variation among HIV-1 subtypes. It is possible that molecular features of the LTR contribute to the unusual profile of the subtype C epidemic in the Brazilian Southern region. To characterize the LTR of Brazilian HIV isolates, we analyzed sequences from 21 infected individuals from Porto Alegre and Salvador cities. Sequences were compared with subtype B and C reference strains from different countries. Phylogenetic analysis showed that 17 (81%) samples were subtype B and four (19%) were subtype C. Common patterns of transcription factor binding sites (TFBS) in subtypes B and C sequences were confirmed and other potential TFBS specific for subtype C were found. Brazilian subtype C sequences contained an additional NF-κB biding site, as previously described for the majority of subtype C isolates. The high level of LTR polymorphisms identified in this study might be important for viral fitness.
HIV-1前病毒激活受长末端重复序列（LTR）-5'病毒启动子区域的控制，该区域在HIV-1各亚型之间存在显著的基因变异。LTR的分子特征可能促成了巴西南部地区C亚型流行的异常情况。为了表征巴西HIV分离株的LTR，我们分析了来自阿雷格里港和萨尔瓦多市21名感染者的序列。将这些序列与来自不同国家的B亚型和C亚型参考菌株进行了比较。系统发育分析表明，17个（81%）样本为B亚型，4个（19%）为C亚型。确认了B亚型和C亚型序列中转录因子结合位点（TFBS）的常见模式，并发现了其他特定于C亚型的潜在TFBS。巴西C亚型序列含有一个额外的NF-κB结合位点，正如之前对大多数C亚型分离株所描述的那样。本研究中鉴定出的高水平LTR多态性可能对病毒适应性很重要。
