We have developed an in vitro transcriptional assay using Escherichia coli RNA polymerase to initiate the replication of peach latent mosaic viroid (PLMVd). Regardless of the polarity of the PLMVd strand used as template, initiation in vitro occurred at the same hairpin structure. These initiation sites correspond to the 5′-ends of two small (280 nt) PLMVd-related RNAs found in infected peach l...

RNA trafficking has broad implications in the systemic spread of infectious agents, plant defense, and the systemic regulation of gene expression. The mechanisms that regulate trafficking remain poorly understood. The non-coding, infectious viroid RNAs are emerging as highly tractable model systems for the investigation of the basic mechanisms of RNA trafficking. Recent studies on viroids have ...

Abstract Viroids are smallest, single-stranded, circular, highly structured plant pathogenic RNAs that do not code for any protein. Viroids belong to two families, the Avsunviroidae and the Pospiviroidae. Members of the Pospiviroidae family adopt a rod-like secondary structure. In this study the most stable secondary structures of citrus viroid variants that reported from Fars province wer...

Eggplant latent viroid (ELVd) can form stable hammerhead structures in its (+) and (-) strands. These ribozymes have the longest helices I reported in natural hammerheads, with that of the ELVd (+) hammerhead being particularly stable (5/7 bp are G-C). Moreover, the trinucleotide preceding the self-cleavage site of this hammerhead is AUA, which together with GUA also found in some natural hamme...

apple scar skin disease (assd) is one of the destructive diseases of pome fruits which is caused by assvd. we report molecular detection of assvd in symptomatic apples cv. red delicious with simultaneous presence of a new variant of hsvd from khorasan razavi province. this is the first report on the association of hsvd with assvd in apple trees showing merely symptoms of apple dapple on the fruit.

Chrysanthemum chlorotic mottle viroid (CChMVd) RNA (398-401 nucleotides) can form hammerhead ribozymes that play a functional role in its replication through a rolling-circle mechanism. In contrast to most other viroids, which adopt rod-like or quasi-rod-like secondary structures of minimal free energy, the computer-predicted conformations of CChMVd and Peach latent mosaic viroid (PLMVd) RNAs a...

A graft-transmissible disease displaying red veins, red blotches and total reddening of leaves in red-berried wine grape (Vitis vinifera L.) cultivars was observed in commercial vineyards. Next-generation sequencing technology was used to identify etiological agent(s) associated with this emerging disease, designated as grapevine redleaf disease (GRD). High quality RNA extracted from leaves of ...

Abstract Citrus exocortis viroid (CEVd), the causal agent of exocortis, is a pathogen that thought to infect all citrus varieties, although it asymptomatic in most. Symptoms develop on susceptible rootstocks, resulting stunting and yield reduction. To aid detection management CEVd, rapid near-field assay was developed using reverse transcription loop-mediated isothermal amplification (RT-LAMP) ...

viroids are smallest, single-stranded, circular, highly structured plant pathogenic rnas that do not code for any protein. viroids belong to two families, the avsunviroidae and the pospiviroidae. members of the pospiviroidae family adopt a rod-like secondary structure. in this study the most stable secondary structures of citrus viroid variants that reported from fars province were drawn. the m...

apple scar skin viroid (assvd) is one of the most destructive viroid diseases in pome fruits orchards which can cause significant economic losses. symptoms of this viroid including scaring, distortion and dappling were seen in some apple orchards in east-northern of iran. sampling was carried out from apple and pear orchards. the rna was extracted by silica capture method from leaves. assvd was...