ABSTRACT A new variety of Nicotiana, N. edwardsonii var. Columbia, was evaluated for its capacity to serve as a new source for virus resistance genes. Columbia was developed from a hybridization between N. glutinosa and N. clevelandii, the same parents used for the formation of the original N. edwardsonii. However, in contrast to the original N. edwardsonii, crosses between Columbia and either ...

Quantitative and qualitative analysis of phenolic compounds in tissue extracts from Centaurea rupestris L. as well as their antiphytoviral activity against Tomato bushy stunt virus was performed. Extracts of flowers, leaves and roots from C. rupestris growing in the wild, as well as extracts from shoots, tissue consisting of callus and shoots and undifferentiated callus grown in vitro, were tes...

A protoplast infection assay has been used to reliably examine the viral RNA encapsidation of turnip crinkle virus (TCV). Analysis of the encapsidation of various mutant viral RNAs revealed that a 186-nucleotide (nt) region at the 3' end of the coat protein (CP) gene, with a bulged hairpin loop of 28 nt as its most essential element, was indispensable for TCV RNA encapsidation. When RNA fragmen...

Three-dimensional (3D) image reconstruction of icosahedral viruses by transmission electron microscopy (TEM) began with the pioneering work on negatively stained samples in Cambridge, UK. This ushered in a new era for virus structure determination and helped lay a firm foundation for subsequent, near atomic resolution X-ray crystallographic studies of viruses such as tomato bushy stunt and sout...

Positive-strand RNA viruses depend on intensive manipulation of subcellular organelles and membranes to create unique viral replication (VROs), which represent the sites robust virus replication. The host endomembrane-based protein-trafficking vesicle-trafficking pathways are specifically targeted by many (+)RNA take advantage their rich resources. We summarize critical roles co-opted endoplasm...

Tomato bushy stunt virus (TBSV), a plus-stranded [(+)] RNA plant virus, incorporates the host metabolic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) into the viral replicase complex. Here, we show that, during TBSV replication in yeast, the yeast GAPDH Tdh2p moves from the cytosol to the peroxisomal membrane surface, the site of viral RNA synthesis. In yeast cells lacking Tdh2p, decr...

Maize necrotic streak virus (MNeSV) is a unique member of the family Tombusviridae that is not infectious by leaf rub inoculation and has a coat protein lacking the protruding domain of aureusviruses, carmoviruses, and tombusviruses (Louie et al., Plant Dis. 84, 1133-1139, 2000). Completion of the MNeSV sequence indicated a genome of 4094 nt. RNA blot and primer extension analysis identified su...

UNLABELLED The multiplicity of infection (MOI), i.e., the number of viral genomes that infect a cell, is an important parameter in virus evolution, which for each virus and environment may have an optimum value that maximizes virus fitness. Thus, the MOI might be controlled by virus functions, an underexplored hypothesis in eukaryote-infecting viruses. To analyze if the MOI is controlled by vir...