Identification and full-genome characterization of a novel circovirus in
giant pandas ( Ailuropoda melanoleuca )
Abstract
The members of the family Circoviridae are considered to be the
smallest autonomously replicating viruses, including two genera,
Circovirus and Cyclovirus. Circoviruses have been found in
a variety of vertebrates, but whether they infect endangered protected
animals has not been studied in much detail. Here, viral metagenomics
and reserve PCR methods were used to detected and verified viral nucleic
acid in the blood samples from giant pandas. According to these methods,
the complete genome sequence of a novel circovirus, the Giant
panda associated circovirus (GPCV) from the blood sample of three giant
panda was identified. The GPCV genome is 2,090 bp in size and reveals
two putative ambisense open-reading frames, encoding the major
structural capsid protein and the replication associated protein,
respectively, the latter having two predicted introns. Pairwise sequence
comparison and phylogenetic analyses indicated GPCV was a putative new
species within genus Circovirus based on the species demarcation
criteria of the International Committee on the Taxonomy of Viruses. It
is the first time that circovirus has been identified from blood samples
of giant pandas. These efforts will contribute to future analyses to
illuminate the evolutionary relationships between classified and newly
identified members of the family Circoviridae.