Characterization and partial genome sequence analysis of Clostera anachoreta granulovirus

The morphological and biological properties as well as partial genomic sequencing of a granulovirus isolated from Clostera anachoreta (Lepidoptera: Notodontidae), C. anachoreta granulovirus (ClanGV), were carried out. The ovoidal occlusion bodies were 337 nm x 170 nm in size, and each granule contained one single rod-shape virion, with a mean size of 250 nm x 46 nm. Granulin had a molecular weight of approximately 30 kDa. ClanGV genome size was estimated as 104.34 kb based on the restriction fragments. The restriction pattern of the ClanGV genome was different from other GVs. A restriction fragment genomic library of ClanGV genome was constructed. The library consisted of nine SalI fragments, seven HindIII fragments and seven EcoRI fragments. One 4.8 kb fragment of the genome, digested by SalI, was sequenced and analyzed. This region was composed of eight unknown ORFs, two baculoviruses homologous gene (vp1054 and lef10) and partial sequence of lef-8. The unknown ORFs included three unique to ClanGV, the other five ORFs were related to baculoviruses. The ORFs, located within this restriction fragment, were compared to homologues in other GVs. The results indicated that ClanGV, CpGV, ClGV, AoGV and PoGV had similar arrangement and orientation of the homologous ORFs. Phylogenetic analysis of VP1054 proteins from 20 baculoviruses indicated that ClanGV was more closely related to CpGV, ClGV, AoGV and PoGV than to other baculoviruses.