Giovanni Chaves-Bedoya

First report of recombination in Potato yellow vein virus (PYVV) in Colombia

Potato yellow vein virus (PYVV) is currently one of the most important viruses that infects potatoes in Colombia and other Andean countries, causing losses in the production of tubers ranging from 25% to 50%. This study analyzed the genetic variability of different viral isolates collected in the department of Narino, Colombia, through bioinformatics analysis of the sequences of three genes encoding the capsid protein (CP), the heat-shock protein 70 (Hsp70) and the minor capsid protein (CPm). We found that CPm is the gene that shows greater diversity, with higher values of nucleotide substitution and evidence of recombination. Based on an analysis of the haplotype map using nucleotide sequences of the CPm, we propose a model of putative recombination in this genomic region. The non-recombinant segments are supported by the results of the program GARD (Genetic Algorithm for Recombination Detection), phylogenetic trees and the paired values of genetic distances of each non-recombinant segments. The model clearly shows that the amino region of the CPm is prone to recombination. To our knowledge, this is the first report of genetic recombination as an evolutionary strategy in the CPm of PYVV.

Respuesta en el desarrollo radicular de Arabidopsis thaliana al extracto foliar de Moringa oleifera

La respuesta del crecimiento de las raices se encuentra mediado por fitorreguladores que participan en todas las etapas de crecimiento y desarrollo de la planta. Un adecuado sistema radicular garantiza el anclaje y absorcion de nutrientes para los procesos metabolicos requeridos en sus etapas fenologicas. Las citoquininas (CK) y auxinas (AIA), son fitorreguladores que desempenan un papel importante en el desarrollo del sistema radicular. Se ha reportado que las hojas de Moringa oleifera son particularmente ricas en zeotina p or lo que la aplicacion de sus extractos puede tener efecto en el desarrollo radicular. Para entender de manera detallada la respuesta de las raices al extracto de Moringa oleifera , se utilizo un sistema in vitro con Arabidopsis thaliana usando.

Ingeniería genética vegetal para resistencia viral y vectores virales en genética reversa

Plants� natural defence mechanism, known as post-transcriptional gene silencing (PTGS), is mediated by small RNA molecules involved in a sequence-specific interaction to inhibit gene expression through RNA silencing. The principle of this mechanism has proven to be an excellent strategy for controlling plant diseases caused by viruses, its importance lying in the fact that currently there are no effective and environmentally-friendly methods for controlling many plant viruses. The nature of PTGS allows ascertaining gene function through reverse genetics by using virus-induced gene silencing (VIGS,) or by RNA interference (iRNA). VIGS is particularly useful for studying genes in crop species. This paper briefly presents how RNA-mediated gene silencing works and its possible applications in designing viral control strategies.