RESUMEN
Tobraviruses, like other (+) stranded RNA viruses of plants, replicate their genome in cytoplasm and use such usual membranous structures like endoplasmic reticulum. Based on the ultrastructural examination of Tobacco rattle virus (TRV)-infected potato and tobacco leaf tissues, in this work we provide evidence of the participation of not only the membranous and vesicular ER structures but also other cell organelles during the viral infection cycle. Non-capsidated TRV PSG particles (potato isolate from the Netherlands) (long and short forms) were observed inside the nucleus while the presence of TRV capsid protein (CP) was detected in the nucleus caryolymph and within the nucleolus area. Both capsidated and non-capsidated viral particles were localized inside the strongly disorganized chloroplasts and mitochondria. The electron-dense TRV particles were connected with vesicular structures of mitochondria as well as with chloroplasts in both potato and tobacco tissues. At 15-30 days after infection, vesicles filled with TRV short particles were visible in mitochondria revealing the expanded cristae structures. Immunodetection analysis revealed the TRV PSG CP epitope inside chloroplast with disorganized thylakoids structure as well as in mitochondria of different tobacco and potato tissues. The ultrastructural analysis demonstrated high dynamics of the main cell organelles during the TRV PSG-Solanaceous plants interactions. Moreover, our results suggest a relationship between organelle changes and different stages of virus infection cycle and/or particle formation.
Asunto(s)
Retículo Endoplásmico/ultraestructura , Orgánulos/ultraestructura , Orgánulos/virología , Enfermedades de las Plantas/virología , Virus de Plantas/fisiología , Virus ARN/fisiología , Proteínas de la Cápside/aislamiento & purificación , Núcleo Celular/ultraestructura , Núcleo Celular/virología , Cloroplastos/ultraestructura , Cloroplastos/virología , Retículo Endoplásmico/virología , Células del Mesófilo/ultraestructura , Células del Mesófilo/virología , Microscopía Electrónica de Transmisión , Mitocondrias/ultraestructura , Mitocondrias/virología , Floema/ultraestructura , Floema/virología , Hojas de la Planta/virología , Virus de Plantas/ultraestructura , Virus ARN/ultraestructura , Solanum tuberosum/virología , Nicotiana/virologíaRESUMEN
The contents of the heterogenous group of polyisoprenoids was found about two orders of magnitude lower in seeds than the amount of polyprenols and/or their carboxylic esters accumulated during vegetation season in leaves. In contrast to leaves, no seeds were found containing more than 0.5 mg of these lipids per gram of dry tissue. Almost 50% had less than 0.01 mg/g - the amount which is the limit of detection by the procedure used in this work. In gymnosperms (10 representatives of Cupressaceae, Pinaceae and Taxaceae) the polyprenol spectra in seeds and in needles were similar. In angiosperms (25 representatives of 13 botanical families) the polyisoprenoid mixture in seeds resembled the minor, additional subfamily found in leaves.