ANNOTATED SEQUENCE RECORD
Complete genome sequence and evolution analysis of Eimeria
stiedai RNA virus 1, a novel member of the family Totiviridae
Received: 20 February 2016 / Accepted: 17 August 2016 / Published online: 30 August 2016
Ó Springer-Verlag Wien 2016
Abstract Eimeria stiedai (E. stiedai) is a coccidian that
infects the liver of the domestic rabbit and may cause severe
hepatic coccidiosis. Virus-like particles in E. stiedai were
discovered by Revets et al. However, the complete genome
sequence of the E. stiedai virus has yet to be determined. A
novel virus was isolated from E. stiedai in the present study.
The complete genome sequence of the E. stiedai virus was
6219 bp in length and contained two open reading frames
(ORFs) with a tetranucleotide overlap (AUGA). ORF1
(2400 bp) encoded a putative coat protein of 799 amino
acids (86.471 kDa) that exhibited a high level of amino acid
sequence similarity to that of Eimeria tenella (E. tenella)
RNA virus 1 (EtRV1; 43 % identity, NC_026140), whereas
ORF2 (3303 bp) encoded a putative RNA-dependent RNA
polymerase (RdRp) of 1100 amino acids (118.850 kDa) that
exhibited a high level of amino acid sequence similarity to
that of the E. tenella RNA virus 1 (EtRV1; 51 % identity,
NC_026140). Phylogenetic analysis revealed that the E.
stiedai virus was a new member of the family Totiviridae.
The sequence data provided sufﬁcient information for clas-
siﬁcation of eimeriaviruses.
E. stiedai is a protozoan parasite that infects the liver of the
domestic rabbit and causes intensive cholestasis and biliary
cirrhosis [1, 2]. Due to the high mortality and morbidity
caused by this parasite, E. stiedai is considered one of the most
important causes of disease faced by rabbit breeders, causing
severe economic losses to the rabbit industry . Currently,
control of coccidiosis in rabbits relies primarily on chemo-
prophylaxis . However, increasing drug resistance and the
problem of chemical medicine residues have prompted the
quest for more-efﬁcient strategies to control this parasite .
Parasite viruses belonging to the family Totiviri-
dae have been discovered in several protozoan parasites,
for example, Trichomonas vaginalis, Giardia lamblia,
Leishmania braziliensis and Eimeria species [6–13].
Leishmania RNA virus 1 (LRV-1) has been demonstrated
to increase the inﬂammatory response by triggering Toll-
like receptor 3 (TLR3) signaling . Furthermore, a
number of reports have suggested that dsRNA viruses
might enhance the pathogenicity of protozoa [15–19].
Viral-RNA-mediated transfection studies have been carried
out with several protozoan parasites, particularly Giardia
lamblia [20–23]. Gene expression in Giardia lamblia can
be manipulated using the 5
(UTRs) of the GLV genome by electroporation of Giardia
lamblia trophozoites infected with GLV. This transfection
system has provided a tool for the genetic manipulation of
Giardia lamblia [22, 23]. Virus-like particles have been
discovered in E. stiedai; however, the complete genome
sequence and taxonomic status of the E. stiedai virus
remain unknown . It also remains unclear whether the
virus affects the pathogenicity of E. stiedai.
C. Xin, B. Wu and J. Li contributed equally to this study.
Electronic supplementary material The online version of this
article (doi:10.1007/s00705-016-3020-7) contains supplementary
material, which is available to authorized users.
& Xuepeng Cai
& Xichen Zhang
College of Veterinary Medicine, Jilin University, 5333 Xi’an
Road, Changchun 130062, China
State Key Laboratory of Veterinary Etiological Biology,
Lanzhou Veterinary Research Institute, Chinese Academy of
Agricultural Sciences, Lanzhou 730046, China
Arch Virol (2016) 161:3571–3576