Paul Konrad Keese

The nucleotide sequence of the genomic RNA of kennedya yellow mosaic tymovirus-Jervis Bay isolate : relationships with potex- and carlaviruses

The nucleotide sequence of the genomic RNA of kennedya yellow mosaic tymovirus-Jervis Bay isolate (KYMV-JB) has been determined. The genome of KYMV-JB is 6362 nucleotide residues long and encodes three major open reading frames. The genomic organization and the encoded proteins of KYMV-JB are very similar to those of three other tymoviruses that have recently been reported. Sequence comparisons revealed that the possible replicase proteins of tymoviruses are closely related to those of potexviruses and carlaviruses, suggesting a close evolutionary relationship among these viruses, despite differences in their genome organization and particle morphology.

Plant viruses: master explorers of evolutionary space

Viruses represent the epitome of genetic diversity, encompassing both DNA and RNA genomes. Their variability probably results from high mutation rates, extensive genetic recombination, gene duplication, large populations and ancient origins. In addition, at least a third of all viral genes may have de novo origins. There is also recent evidence that additional novelty may be generated by genetic recombination between viruses and their plant hosts. Viruses are indeed master explorers of evolutionary space.

The primary structure of the virion protein gene and encoded protein of erysimum latent tymovirus.

The nucleotide sequence of the virion protein (VP) gene of erysimum latent tymovirus (ELV) has been determined and the amino acid sequence of the VP deduced and confirmed by peptide analysis. The ELV VP is larger than the VPs of other tymoviruses because it has, unexpectedly, 11 more amino acid residues at its N terminus. The amino acid sequences of the VPs of ELV and four other tymoviruses align unequivocally and their relationships, as assessed from the percentage of identical residues, correlate well with previously reported serological tests which have shown ELV to be distant from other tymoviruses.