RESUMO

Jatropha gossypifolia is a weed that is commonly found with yellow mosaic symptoms growing along the roadside and in close proximity to cultivated crops in many farming communities in Jamaica. For the first time, the complete genome sequence of a new begomovirus, designated jatropha mosaic virus-[Jamaica:Spanish Town:2004] (JMV-[JM:ST:04]), was determined from field-infected J. gossypifolia in the western hemisphere. DNA-A nucleotide sequence comparisons showed closest identity (84 %) to two tobacco-infecting viruses from Cuba, tobacco mottle leaf curl virus-[Cuba:Sancti Spiritus:03] (TbMoLCV-[CU:SS:03]) and tobacco leaf curl Cuba virus-[Cuba:Taguasco:2005] (TbLCuCUV-[CU:Tag:05]), and two weed-infecting viruses from Cuba and Jamaica, Rhynchosia rugose golden mosaic virus-[Cuba:Camaguey:171:2009] (RhRGMV- [CU:Cam:171:09]) and Wissadula golden mosaic St. Thomas virus-[Jamaica:Albion:2005] (WGMSTV-[JM:Alb:05]). Phylogenetic analysis revealed that JMV-[JM:ST:04] is most closely related to tobacco and tomato viruses from Cuba and WGMSTV-[JM:Alb:05], a common malvaceous-weed-infecting virus from eastern Jamaica, and that it is distinct from begomoviruses infecting Jatropha species in India and Nigeria.

Assuntos

Begomovirus/genética , Genoma Viral/genética , Jatropha/virologia , Doenças das Plantas/virologia , Folhas de Planta/virologia , Sequência de Aminoácidos , Sequência de Bases , Begomovirus/isolamento & purificação , Proteínas do Capsídeo/genética , Cuba , DNA Viral/genética , Variação Genética , Jamaica , Solanum lycopersicum/virologia , Filogenia , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , Nicotiana/virologia

RESUMO

This preliminary report sought to provide insight into the genetic diversity of human immunodeficiency virus drug resistance (HIVDR) in Jamaica. This was done by investigating the genetic diversity associated with drug resistance in pregnant women living with HIV attending antenatal clinics in Kingston, Jamaica. Blood samples were collected and viral RNA were extracted and analysed. The protease and reverse transcriptase (Pro-RT) genes were amplified using the nested polymerase chain reaction (PCR) method. Polymerase chain reaction amplicons were obtained for nine of 16 patients (56%), of which five (55%) were antiretroviral (ARV) drug naïve and four (45%) were treatment experienced. Three minor protease resistant-conferring mutations (A71AT, A71V, A71T) and five mutations conferring high to low-level resistance (K219EK, T69S, K103S, G190A and K103N) were detected in the RT region. More than 50% of the resistance mutations found were detected in ARV drug naïve individuals, implying that viruses are being transmitted with the ARV resistance. These preliminary results will inform the health practitioners of the level of drug resistance that is being transmitted as well as strengthen the need to initiate a national baseline survey on HIVDR in Jamaica.

RESUMO

Partial genome segments of a begomovirus were previously amplified from Wissadula amplissima exhibiting yellow-mosaic and leaf-curl symptoms in the parish of St. Thomas, Jamaica and this isolate assigned to a tentative begomovirus species, Wissadula golden mosaic St. Thomas virus. To clone the complete genome of this isolate of Wissadula golden mosaic St. Thomas virus, abutting primers were designed to PCR amplify its full-length DNA-A and DNA-B components. Sequence analysis of the complete begomovirus genome obtained, confirmed that it belongs to a distinct begomovirus species and this isolate was named Wissadula golden mosaic St. Thomas virus-[Jamaica:Albion:2005] (WGMSTV-[JM:Alb:05]). The genome of WGMSTV-[JM:Alb:05] is organized similar to that of other bipartite Western Hemisphere begomoviruses. Phylogenetic analyses placed the genome components of WGMSTV-[JM:Alb:05] in the Abutilon mosaic virus clade and showed that the DNA-A component is most closely related to four begomovirus species from Cuba, Tobacco leaf curl Cuba virus, Tobacco leaf rugose virus, Tobacco mottle leaf curl virus, and Tomato yellow distortion leaf virus. The putative Rep-binding-site motif in the common region of WGMSTV-[JM:Alb:05] was observed to be identical to that of Chino del tomate virus-Tomato [Mexico:Sinaloa:1983], Sida yellow mosaic Yucatan virus-[Mexico:Yucatan:2005], and Tomato leaf curl Sinaloa virus-[Nicaragua:Santa Lucia], suggesting that WGMSTV-[JM:Alb:05] is capable of forming viable pseudo-recombinants with these begomoviruses, but not with other members of the Abutilon mosaic virus clade. Biolistic inoculation of test plant species with partial dimers of the WGMSTV-[JM:Alb:05] DNA-A and DNA-B components showed that the virus was infectious to Nicotiana benthamiana and W. amplissima and the cultivated species Phaseolus vulgaris (kidney bean) and Lycopersicon esculentum (tomato). Infected W. amplissima plants developed symptoms similar to symptoms observed under field conditions, confirming that this virus is a causal agent of Wissadula yellow mosaic disease in W. amplissima.

Assuntos

Begomovirus/classificação , Begomovirus/crescimento & desenvolvimento , Malvaceae/virologia , Sequência de Bases , Begomovirus/genética , Begomovirus/isolamento & purificação , Análise por Conglomerados , Primers do DNA/genética , DNA Viral/química , DNA Viral/genética , Ordem dos Genes , Genes Virais , Genoma Viral , Jamaica , Solanum lycopersicum/virologia , Dados de Sequência Molecular , Phaseolus/virologia , Filogenia , Reação em Cadeia da Polimerase/métodos , Análise de Sequência de DNA , Homologia de Sequência , Sintenia , Nicotiana/virologia

RESUMO

In September 1998, tomato plants in Barbados exhibited symptoms of severe leaf curling without marginal chlorosis. These symptoms were often associated with an increase in whitefly (Bemisia tabaci) populations. DNA was extracted from leaf tissue from symptomatic tomato plants. Polymerase chain reaction (PCR) was performed with DNA-A degenerate primer pair PAC1v1978/PAV1c715, which amplifies part of the rep gene, the cp gene, and the common region (CR), and with DNA-B primer pair PBC1v2039/PBV1c800, which amplifies part of the bc1 and bv1 genes and the CR (2). The amplified PCR fragments of DNA-A and DNA-B were 1.3 and 1.4 kb, respectively, which are the expected sizes from bipartite, whitefly-transmitted geminiviruses of the Western Hemisphere (2). DNA sequence of the cloned fragments of DNA-A and DNA-B are available as GenBank No. AF213013 and AF213014, respectively. The 181 nucleotides of the CR of DNA-A had a nucleotide identity of 96% with the CR of DNA-B, which indicates that this is a bipartite begomovirus. Pairwise comparisons using DNASTAR (DNASTAR, Madison, WI) of the sequenced part of DNA-A was most similar to Cabbage leaf curl virus (CaLCuV, 69%, U65529) and Squash leaf curl virus extended host range isolate (SqLCV-E, 64%, M38183), and <59% to 13 other bipartite Western Hemisphere geminiviruses and Tomato yellow leaf curl virus from Israel (X15656). Pairwise comparisons of the DNA-B fragment sequence was 59 and 55% similar to CaLCuV (U65530) and SqLCV-E (M38182), respectively. Phylogenetic analysis of DNA-A of the major groups of Western Hemisphere begomoviruses placed the Barbados tomato-infecting geminivirus in the cluster with CaLCuV and SqLCV-E (1), while DNA-B analysis placed it with CaLCuV. The DNA-A amplified fragment was used as a probe at high stringency with the dot blot hybridization assay using the Genius II labeling and detection kit (Boeringer Mannheim) to detect this geminivirus in tomato and several other plant species, which had typical geminiviral symptoms. Strong hybridization signals were obtained for all 23 tomato plants with symptoms, weak signals were observed for two of three muskmelon and two of seven watermelon plants, all with leaf curling symptoms. No hybridization signals were observed for peppers with leaf curling symptoms and two weed species, Macroptilium lathyroides and Rhynchosia minima, with golden mosaic symptoms or with the symptomless plant species used as negative controls. The weak signals observed from watermelon and muskmelon samples indicated the presence of low virus titer or geminiviruses distinct from this tomato virus. The presence of viral DNA in these two plant species was confirmed by PCR with degenerate primers described above. Resulting database searches of sequences in the GenBank revealed that the Barbados tomato virus appears to be a previously unreported virus. This new virus is given the provisional name Tomato leaf curl Barbados virus (ToLCBBV). References: (1) J. C. Faria et al. Phytopathology 84:321, 1994. (2) M. R. Rojas et al. Plant Dis. 77:340, 1993.