Background and Aims: Viroids are smallest known plant pathogens and cause several economically significant diseases. Until recently, viroid detection relied mainly on biological tests and indexing. Today various diagnostic techniques such as nucleic acid hybridization, southern blot and reverse transcription coupled with polymerase chain reaction (RT-PCR) are being used for detection and diagno...

In grapevine, serine peptidases from the subtilase family were recently associated to Plasmopara viticola resistance. This family in grapevine, first characterized in 2014, was re-analyzed last year and 82 subtilase genes were identified. However, in November of 2016, the National Center for Biotechnology Information database (NCBI) made a new public release of the grapevine genome annotation b...

We characterized the peach latent mosaic viroid (PLMVd) replication intermediates that accumulate in infected peach leaves and determined the tissue and subcellular localization of the RNA species. Using in situ hybridization, we showed that PLMVd strands of both plus and minus polarities concentrate in the cells forming the palisade parenchyma. At the cellular level, PLMVd was found to accumul...

The complete nucleotide sequence of apple scar skin viroid(ASSV) has been established, and a probable secondary structure is proposed. A single-stranded circular ASSV RNA consists of 330 nucleotides and can assume the rodlike conformation with extensive base-pairing characteristic of all the known viroids. ASSV shows low sequence homologies with other viroids and lacks the central conserved reg...

Due to their small size, locating pathogenic RNAs, such as viroids, in plant tissue and cell organelles has been difficult. Viroids are circular single-stranded RNA virus-like pathogens that reduce growth, vigor, yield economically important crops potato, tomato, hops citrus. Viroid infections plants largely diagnosed by dot blot hybridization, PAGE-gels, or RT-PCR. Because traditional situ hyb...

The intracellular localization of viroids has been investigated by viroid-specific in situ hybridization and analysis by digital microscopy of the distribution of the fluorescent hybridization signals. Isolated nuclei from green leaf tissue of tomato plants infected with potato spindle tuber viroid (PSTVd) were bound to microscope slides, fixed with formaldehyde and hybridized with biotinylated...

The elucidation of the structures of viroids, noncoding infectious RNA species, is paramount to obtain an understanding of the various aspects of their life cycles (including replication, transport and pathogenesis). In general, the secondary structures of viroids have been predicted using computer software programs which have been shown to possess several important limitations. Clearly, the pr...

BACKGROUND Alignment analysis of the Vv-miRNAs identified from various grapevine cultivars indicates that over 30% orthologous Vv-miRNAs exhibit a 1-3 nucleotide discrepancy only at their ends, suggesting that this sequence discrepancy is not a random event, but might mainly derive from divergence of cultivars. With advantages of miR-RACE technology in determining precise sequences of potential...

The nucleotide sequence and secondary structure of two representative variants from the Group III citrus viroids. CVd-IIIa (297 bases) and CVd-IIIb (294 bases) were determined. The variants are related to the apple scar skin viroid (ASSVd) family. Although smaller in size than any of the ASSVd-related viroids, the central conserved region as well as most of the terminal conserved region of ASSV...