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Virus-like particles in Eimeria tenella are associated with multiple RNA segments
Qianzhong Han1, Jianhua Li, Pengtao Gong
1College of Animal Science and Veterinary Medicine, Jilin University, 5333 Xian Road, Changchun 130062, China.
Experimental Parasitology
|December 28, 2010
Summary
Researchers discovered a novel virus, Eimeria tenella virus (ETV), in E. tenella oocysts. This double-stranded RNA virus exhibits RNA-dependent RNA polymerase activity and is the first virus identified in this important parasite.
Area of Science:
- Virology
- Parasitology
- Molecular Biology
Background:
- Eimeria tenella is a significant protozoan parasite causing coccidiosis in poultry.
- The presence and characterization of viruses within Eimeria species are largely unexplored.
- Understanding parasitic viruses can offer new insights into parasite biology and control.
Purpose of the Study:
- To identify and characterize novel viral agents within Eimeria tenella.
- To investigate the nature of extrachromosomal nucleic acids in E. tenella.
- To establish the existence of a virus in E. tenella.
Main Methods:
- Isolation and purification of nucleic acids from Eimeria tenella sporulated oocysts.
- Analysis of RNA segments using RNase A digestion and size determination.
- Detection of RNA-dependent RNA polymerase (RDRP) activity in parasite extracts.
- Electron microscopy (EM) and sucrose density gradient centrifugation for virus-like particle (VLP) characterization.
Main Results:
- Three extrachromosomal double-stranded RNA (dsRNA) segments (1.4, 2.4, and 3.6 kb) were identified.
- These dsRNAs demonstrated resistance to RNase A digestion under high salt conditions.
- RDRP activity was confirmed in crude parasite extracts.
- Purified VLPs with a diameter of approximately 38 nm were observed via EM.
Conclusions:
- A novel virus, designated Eimeria tenella virus (ETV), has been isolated from E. tenella.
- ETV possesses dsRNA genomes and exhibits RDRP activity, consistent with known RNA viruses.
- This discovery marks the first isolation of a virus from E. tenella, opening new avenues for research.
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