A single nucleotide substitution converts potato spindle tuber viroid (PSTVd) from a noninfectious to an infectious RNA for nicotiana tabacum.

@article{Wassenegger1996ASN,
  title={A single nucleotide substitution converts potato spindle tuber viroid (PSTVd) from a noninfectious to an infectious RNA for nicotiana tabacum.},
  author={Mich{\`e}le Wassenegger and R. L. Spieker and S Thalmeir and F. -U. Gast and Leonhard Riedel and Heinz Ludwig S{\"a}nger},
  journal={Virology},
  year={1996},
  volume={226 2},
  pages={
          191-7
        }
}
Mechanical inoculation of Nicotiana tabacum with the PSTVd isolate KF 440-2 from the host plant tomato resulted in the de novo emergence, replication, and accumulation of a new "tobacco variant," designated PSTVd NT. It produces no symptoms in tobacco but, like PSTV KF 440-2, severe ones in tomato. The sequence analysis of PSTVd NT revealed a single nucleotide substitution from C-->U at position 259. Autonomous viroid replication was also induced in tobacco by genomic integration of oligomeric… 
Detection of Potato spindle tuber viroid sequence variants derived from PSTVd-infected Phelipanche ramosa in flower organs of tomato plants
TLDR
It is found that the PSTVd G241-C and C208-U variants were able to replicate in systemic leaves and floral organs of tomato plants, while the PSTDd C227-U variant did not develop systemic infection.
Replication of Potato spindle tuber viroid in cultured cells of tobacco and Nicotiana benthamiana: the role of specific nucleotides in determining replication levels for host adaptation.
TLDR
An electroporation protocol to inoculate cultured cells of tobacco and Nicotiana benthamiana with in vitro transcripts of Potato spindle tuber viroid (PSTVd) to characterize viroid structural features that determine replication efficiency at the cellular level provides insights about PSTVd structures that modulate replication efficiency in adapting to a specific host.
Inhibition of Cell Growth and Shoot Development by a Specific Nucleotide Sequence in a Noncoding Viroid RNA
TLDR
It is demonstrated that specific nucleotides in a noncoding, pathogenic RNA have a profound effect in altering distinct cellular responses, which then lead to well-defined alterations in plant growth and developmental patterns.
Inhibition of Cell Growth and Shoot Development by a Specific Nucleotide Sequence in a Noncoding Viroid RNA Article, publication date, and citation information can be found at www.plantcell.org/cgi/doi/10.1105/tpc.011585.
TLDR
It is demonstrated that specific nucleotides in a noncoding, pathogenic RNA have a profound effect in altering distinct cellular responses, which then lead to well-defined alterations in plant growth and developmental patterns.
Biological and molecular analysis of the pathogenic variant C3 of potato spindle tuber viroid (PSTVd) evolved during adaptation to chamomile (Matricaria chamomilla)
TLDR
A new PSTVd variant C3 is described, evolved through sequence adaptation to the host chamomile after biolistic inoculation with PSTVD-KF440-2, which causes extraordinary strong (‘lethal’) symptoms.
Identification and Molecular Mechanisms of Key Nucleotides Causing Attenuation in Pathogenicity of Dahlia Isolate of Potato Spindle Tuber Viroid
TLDR
Results indicate that the nucleotides at positions 42 and 64 are in concert with the ones at positions 43, 310, and 311/312, which determines the slower and stable accumulation of PSTVd-D without eliciting excessive host defense responses thus contributing in the attenuation of disease symptom.
Characterization of the RNA motif responsible for the specific interaction of potato spindle tuber viroid RNA (PSTVd) and the tomato protein Virp1.
TLDR
It is found that two asymmetric internal loops within the PSTVd (+) RNA, each composed of the sequence elements 5'-ACAGG and CUCUUCC-5', are responsible for the specific RNA-protein interaction.
Silencing of transcription factor encoding gene StTCP23 by small RNAs derived from the virulence modulating region of potato spindle tuber viroid is associated with symptom development in potato
TLDR
Results indicate that sRNAs derived from the VMR of PSTVd-RG1 direct silencing of StTCP23 expression is disrupted, thereby disrupting the signaling pathways regulating GA metabolism and leading to plant stunting and formation of small and spindle-shaped tubers.
Molecular properties of potato spindle tuber viroid (PSTVd) isolates of the Russian Research Institute of Phytopathology
The complete nucleotide sequences of more than 100 isolates of Potato spindle tuber viroid (PSTVd) collected from locations in the territory of Russia and the former USSR have been determined. These
...
1
2
3
4
5
...

References

Role of a bulged A residue in a specific RNA-protein interaction.
TLDR
While functional groups on N1, C2, C6, N7, and 2'OH of the bulged A can be substituted without greatly changing protein binding, bulky substituents cannot be tolerated at these positions.