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. 1977 Jan;4(1):177–194. doi: 10.1093/nar/4.1.177

Conformation of viroids.

K Henco, D Riesner, H L Sanger
PMCID: PMC342418  PMID: 866174

Abstract

Viroids are uncoated infectious RNA molecules (MW 107 000-127 000) known as pathogens of certain higher plants. Thermodynamic and kinetic studies were carried out on highly purified viroid preparations by applying UV-absorption melting analysis and temperature jump methods. The thermal denaturation of viroids is characterized by high thermal stability, high cooperativity and a high degree of base pairing. Two relaxation processes could be resolved; a process in the sec range could be evaluated as an independent all-or-none-transition with the following properties: reaction enthalpy= 550 kcal/mol, activation enthalpy of the dissociation = 470 kcal/mol; G : C content = 72 %. These data indicate the existence of an uninterrupted double helix of 52 base pairs. A process in the msec range involves 15 - 25 base pairs which are most probably distributed over several short double helical stretches. A tentative model for the secondary structure of viroids isproposed and the possible functional implications of their physicochemical properties are discussed.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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