Suchergebnisse

HIV-1 RNAs are generated through a complex splicing mechanism, resulting in a great diversity of transcripts, which are classified in three major categories: unspliced, singly spliced (SS), and doubly spliced (DS). Knowledge on HIV-1 RNA splicing in vivo and by non-subtype B viruses is scarce. Here we analyze HIV-1 RNA splice site usage in CD4+CD25+ lymphocytes from HIV-1-infected individuals through pyrosequencing. HIV-1 DS and SS RNAs were amplified by RT-PCR in 19 and 12 samples, respectively. 13,108 sequences from HIV-1 spliced RNAs, derived from viruses of five subtypes (A, B, C, F, G), were identified. In four samples, three of non-B subtypes, five 3' splice sites (3'ss) mapping to unreported positions in the HIV-1 genome were identified. Two, designated A4i and A4j, were used in 22% and 25% of rev RNAs in two viruses of subtypes B and A, respectively. Given their close proximity (one or two nucleotides) to A4c and A4d, respectively, they could be viewed as variants of these sites. Three 3'ss, designated A7g, A7h, and A7i, located 20, 32, and 18 nucleotides downstream of A7, respectively, were identified in a subtype C (A7g, A7h) and a subtype G (A7i) viruses, each in around 2% of nef RNAs. The new splice sites or variants of splice sites were associated with the usual sequence features of 3'ss. Usage of unusual 3'ss A4d, A4e, A5a, A7a, and A7b was also detected. A4f, previously identified in two subtype C viruses, was preferentially used by rev RNAs of a subtype C virus. These results highlight the great diversity of in vivo splice site usage by HIV-1 RNAs. The fact that four of five newly identified splice sites or variants of splice sites were detected in non-subtype B viruses allows anticipating an even greater diversity of HIV-1 splice site usage than currently known. ; This work was supported by the Francisco Díez-Fuertes is supported by the Sara Borrell postdoctoral Program of the Spanish Government 2012 CD12/00515. This work was also supported by Ministerio de Economía y Competitividad, Spain (URL: http://www.mineco.gob.es/portal/site/mineco/) Grant # SAF2010-20961, Grant # SAF2013-48488-P to MMT and Instituto de Salud Carlos III (URL: http://www.isciii.es) Grant # MPY 1194/12 to MMT. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. ; Sí

We recently reported the rapid expansion of an HIV-1 subtype F cluster among men who have sex with men (MSM) in the region of Galicia, Northwest Spain. Here we update this outbreak, analyze near full-length genomes, determine phylogenetic relationships, and estimate its origin. For this study, we used sequences of HIV-1 protease-reverse transcriptase and env V3 region, and for 17 samples, near full-length genome sequences were obtained. Phylogenetic analyses were performed via maximum likelihood. Locations and times of most recent common ancestors were estimated using Bayesian inference. Among samples analyzed by us, 100 HIV-1 F1 subsubtype infections of monophyletic origin were diagnosed in Spain, including 88 in Galicia and 12 in four other regions. Most viruses (n = 90) grouped in a subcluster (Galician subcluster), while 7 from Valladolid (Central Spain) grouped in another subcluster. At least 94 individuals were sexually-infected males and at least 71 were MSM. Seventeen near full-length genomes were uniformly of F1 subsubtype. Through similarity searches and phylogenetic analyses, we identified 18 viruses from four other Western European countries [Switzerland (n = 8), Belgium (n = 5), France (n = 3), and United Kingdom (n = 2)] and one from Brazil, from samples collected in 2005-2011, which branched within the subtype F cluster, outside of both Spanish subclusters, most of them corresponding to recently infected individuals. The most probable geographic origin and age of the Galician subcluster was Ferrol, Northwest Galicia, around 2007, while the Western European cluster probably emerged in Switzerland around 2002. In conclusion, a recently expanded HIV-1 subtype F cluster, the largest non-subtype B cluster reported in Western Europe, continues to spread among MSM in Spain; this cluster is part of a larger cluster with a wide geographic circulation in diverse Western European countries. ; This work received support from the Dirección General de Farmacia, Ministerio de Sanidad, Servicios Sociales e Igualdad, Government of Spain, grant EC11-272; European Network of Excellence EUROPRISE (Rational Design of HIV Vaccines and Microbicides), grant LSHP-CT-2006-037611; European Research Infrastructures for Poverty Related Diseases (EURIPRED). Seventh Framework Programme: FP7-Capacities-infrastructures-2012-1, grant agreement 312661; Instituto de Salud Carlos III, Subdirección General de Evaluación, and Fondo Europeo de Desarrollo Regional (FEDER), Plan Nacional I + D + I, through project RD12/0017/0026; Consellería de Sanidade, Government of Galicia, Spain (MVI 1291/08); and the Osakidetza-Servicio Vasco de Salud, Basque Country, Spain (MVI-1255-08). Marcos Pérez-Losada was supported by a DC D-CFAR Research Award from the District of Columbia Developmental Center for AIDS Research (P30AI087714) and by an University Facilitating Fund award from George Washington University. Aurora Fernández-García is supported by CIBER in Epidemiology and Public Health, Instituto de Salud Carlos III, Madrid, Spain. ; Sí