Differences Between Viroids and Prions
In this article we will discuss about Differences Between Viroids and Prions. In our previous article we have discussed about;
- Prions: Definition, Structure, Function, Disease, Prevention, Control, Treatment, Transmission.
- Viroids Definition, Infection, Structure, Examples, Diagnostic, Origin, Disease.
Viroid:
Viroids are known as the smallest infectious pathogens which are made up solely of a short strand of circular, single-stranded self-replicating RNA that has no protein coating.
In 1971, a plant pathologist named Theodor Otto Diener first discovered the Viroids. He found an acellular particle when he was working in an Agriculture Research Service and named this particle as viroid, meaning “virus-like.” At present-33 species of viroid have been identified. Read More…Prions:
Prion is an abnormal or misfolded protein that causes fatal disease in animals and humans by transmitting their misfolded shape onto normal variants of the same protein.
Prion causes untreatable, fatal, and transmissible neurodegenerative diseases in both humans and animals. In this disease, a progressive decline is occurring in brain function. Read More…
Differences Between Viroids and Prions
| Topic | Viroids | Prions |
| Nature | It is an infectious RNA particle | It is an infectious protein particle. |
| Composition | It is composed of only small single stranded circular RNA. | It is only composed of Protein. |
| Nucleic acid | Present | Absent |
| Protein coat | Absent | Not known |
| Inactivation | Viroids are inactivated by ribonuclease digestion. | Prions are inactivated by proteinase K and trypsin digestion. |
| Resistant | Resistant to proteinase K and trypsin digestion | Resistant to ribonuclease treatment. |
| Size | Viroids are smaller than virus | Smaller than viroids. |
| Host | Viroid infects only higher plants (Exception: hepatitis D virus in humans is similar to viroid) | Prions infect animals causing neurological degenerative diseases |
| Disease Name | Common plant diseases include Potato Spindle tuber disease, Chrysanthemum stunt disease. | ‘Mad cow disease’ (Bovine spongiform encephalopathy) in cow and Scrapie disease in sheep and goat, Creutzfeldt-Jakob Disease (CJD), Kuru, and Gerstmann-Strausler-Sheinker syndrome in humans. |
