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1.
Zootaxa ; 4243(1): 75-96, 2017 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-28610172

RESUMEN

Sturnira is the most speciose genus of New World leaf-nosed bats (Phyllostomidae). We name Sturnira adrianae, new species. This taxon is born polytypic, divided into a larger subspecies (S. a. adrianae) widespread in the mountains of northern and western Venezuela, and northern Colombia, and a smaller subspecies (S. a. caripana) endemic to the mountains of northeastern Venezuela. The new species inhabits evergreen, deciduous, and cloud forests at mainly medium (1000-2000 m) elevations. It has long been confused with S. ludovici, but it is more closely related to S. oporaphilum. It can be distinguished from other species of Sturnira by genetic data, and based on discrete and continuously varying characters. Within the genus, the new species belongs to a clade that also includes S. oporaphilum, S. ludovici, S. hondurensis, and S. burtonlimi. The larger new subspecies is the largest member of this clade. The two new subspecies are the most sexually dimorphic members of this clade. The smaller new subspecies is restricted to small mountain systems undergoing severe deforestation processes, therefore can be assigned to the Vulnerable (VU) conservation category of the International Union for Conservation of Nature (IUCN).


Asunto(s)
Quirópteros , Animales , Colombia , Conservación de los Recursos Naturales , Bosques , Venezuela
2.
Zootaxa ; 3620: 179-91, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-26120703

RESUMEN

In this article, a new species of salamander of the genus Bolitoglossa (Eladinea) from the cloud forest near La Mucuy in Sierra Nevada de Mérida, Venezuelan Andes, is described. Bolitoglossa mucuyensis sp. nov. differs from all Venezuelan salamanders, except B. orestes, by a larger SVL/TL ratio, and from La Culata salamander B. orestes by a reduced webbing extension of the front and hind limbs. Additionally, B. mucuyensis sp. nov. and B. orestes diverge 3.12% in terms of the nucleotide sequence of the 16S rRNA gene, as previously reported, and in 8.1% for the cytb gene as shown in this study.


Asunto(s)
Urodelos/anatomía & histología , Urodelos/clasificación , Proteínas Anfibias/genética , Animales , Citocromos b/genética , Femenino , Masculino , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Especificidad de la Especie , Urodelos/genética , Venezuela
3.
J Agric Food Chem ; 59(18): 10006-12, 2011 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-21819140

RESUMEN

The virus-resistant, transgenic commercial papaya Rainbow and SunUp (Carica papaya L.) have been consumed locally in Hawaii and elsewhere in the mainland United States and Canada since their release to planters in Hawaii in 1998. These papaya are derived from transgenic papaya line 55-1 and carry the coat protein (CP) gene of papaya ringspot virus (PRSV). The PRSV CP was evaluated for potential allergenicity, an important component in assessing the safety of food derived from transgenic plants. The transgene PRSV CP sequence of Rainbow papaya did not exhibit greater than 35% amino acid sequence homology to known allergens, nor did it have a stretch of eight amino acids found in known allergens which are known common bioinformatic methods used for assessing similarity to allergen proteins. PRSV CP was also tested for stability in simulated gastric fluid and simulated intestinal fluid and under various heat treatments. The results showed that PRSV CP was degraded under conditions for which allergenic proteins relative to nonallergens are purported to be stable. The potential human intake of transgene-derived PRSV CP was assessed by measuring CP levels in Rainbow and SunUp along with estimating the fruit consumption rates and was compared to potential intake estimates of PRSV CP from naturally infected nontransgenic papaya. Following accepted allergenicity assessment criteria, our results show that the transgene-derived PRSV CP does not pose a risk of food allergy.


Asunto(s)
Alérgenos/inmunología , Proteínas de la Cápside/genética , Proteínas de la Cápside/inmunología , Carica/inmunología , Plantas Modificadas Genéticamente/inmunología , Potyvirus/química , Antígenos Virales/inmunología , Carica/virología , Estabilidad de Medicamentos , Hipersensibilidad a los Alimentos/inmunología , Frutas/inmunología , Calor , Humanos , Plantas Modificadas Genéticamente/virología
4.
BMC Genet ; 12: 23, 2011 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-21303555

RESUMEN

BACKGROUND: Phytophthora infestans (Mont.) de Bary, the causal agent of potato late blight, is responsible for tremendous crop losses worldwide. Countries in the northern part of the Andes dedicate a large proportion of the highlands to the production of potato, and more recently, solanaceous fruits such as cape gooseberry (Physalis peruviana) and tree tomato (Solanum betaceum), all of which are hosts of this oomycete. In the Andean region, P. infestans populations have been well characterized in Ecuador and Peru, but are poorly understood in Colombia and Venezuela. To understand the P. infestans population structure in the Northern part of the Andes, four nuclear regions (ITS, Ras, ß-tubulin and Avr3a) and one mitochondrial (Cox1) region were analyzed in isolates of P. infestans sampled from different hosts in Colombia and Venezuela. RESULTS: Low genetic diversity was found within this sample of P. infestans isolates from crops within several regions of Colombia and Venezuela, revealing the presence of clonal populations of the pathogen in this region. We detected low frequency heterozygotes, and their distribution patterns might be a consequence of a high migration rate among populations with poor effective gene flow. Consistent genetic differentiation exists among isolates from different regions. CONCLUSIONS: The results here suggest that in the Northern Andean region P. infestans is a clonal population with some within-clone variation. P. infestans populations in Venezuela reflect historic isolation that is being reinforced by a recent self-sufficiency of potato seeds. In summary, the P. infestans population is mainly shaped by migration and probably by the appearance of variants of key effectors such as Avr3a.


Asunto(s)
Variación Genética , Genética de Población , Phytophthora infestans/genética , Colombia , Genes ras , Tubulina (Proteína)/genética , Venezuela
5.
Plant Cell Rep ; 30(5): 681-7, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21212960

RESUMEN

In this opinion article, we briefly review the status of crop biotechnology research-with emphasis on the development of GM crops-in Jamaica and Venezuela. We focus on the transgenic papayas developed for both countries, and examine the factors hindering not only the development and application of this biotechnological commodity for the improvement of agricultural productivity, but also on the challenges influencing societal acceptance of the technology.


Asunto(s)
Biotecnología/tendencias , Carica/genética , Enfermedades de las Plantas/prevención & control , Plantas Modificadas Genéticamente/genética , Biotecnología/economía , Carica/virología , Productos Agrícolas/genética , Productos Agrícolas/virología , Regulación Gubernamental , Jamaica , Enfermedades de las Plantas/virología , Inmunidad de la Planta/genética , Plantas Modificadas Genéticamente/virología , Potyvirus/inmunología , Potyvirus/patogenicidad , Opinión Pública , Venezuela
6.
Methods Mol Biol ; 286: 399-430, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15310936

RESUMEN

We present data concerning the creation of transgenic papayas resistant to Papaya ringspot virus (PRSV) and their adoption by three different countries: the United States (e.g., Hawaii), Jamaica, and Venezuela. Although the three sets of transgenic papayas showed effective resistance to PRSV, the adoption rate in each country has varied from full utilization in Hawaii to aggressive testing but delay in deregulating of the product in Jamaica to rejection at an early stage in Venezuela. Factors that contributed to the rapid adoption in Hawaii include a timely development of the transgenic product, PRSV causing severe damage to the papaya industry, close collaboration between researchers and the industry, and the existence of procedures for deregulating a transgenic product. In Jamaica, the technology for developing the initial field-testing of the product progressed rather rapidly, but the process of deregulation has been slowed down owing to the lack of sustained governmental efforts to complete the regulatory procedures for transgenic crops. In Venezuela, the technology to develop and greenhouse test the transgenic papaya has moved abreast with the Jamaica project, but the field testing of the transgenic papaya within the country was stopped very early on by actions by people opposed to transgenic products. The three cases are discussed in an effort to provide information on factors, other than technology, that can influence the adoption of a transgenic product.


Asunto(s)
Carica/genética , Genoma Viral , Nepovirus/patogenicidad , Plantas Modificadas Genéticamente/fisiología , Secuencia de Aminoácidos , Carica/virología , Hawaii , Inmunidad Innata/genética , Jamaica , Datos de Secuencia Molecular , Nepovirus/genética , Enfermedades de las Plantas/virología , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/virología , Venezuela
7.
Plant Dis ; 88(5): 516-522, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-30812656

RESUMEN

Local varieties of papaya grown in the Andean foothills of Mérida, Venezuela, were transformed independently with the coat protein (CP) gene from two different geographical Papaya ringspot virus (PRSV) isolates, designated VE and LA, via Agrobacterium tumefaciens. The CP genes of both PRSV isolates show 92 and 96% nucleotide and amino acid sequence similarity, respectively. Four PRSV-resistant R0 plants were intercrossed or selfed, and the progenies were tested for resistance against the homologous isolates VE and LA, and the heterologous isolates HA (Hawaii) and TH (Thailand) in greenhouse conditions. Resistance was affected by sequence similarity between the transgenes and the challenge viruses: resistance values were higher for plants challenged with the homologous isolates (92 to 100% similarity) than with the Hawaiian (94% similarity) and, lastly, Thailand isolates (88 to 89% similarity). Our results show that PRSV CP gene effectively protects local varieties of papaya against homologous and heterologous isolates of PRSV.

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