Analysis of the genomic sequence of Philosamia cynthia nucleopolyhedrin virus and comparison with Antheraea pernyinucleopolyhedrin virus

Abstract

BackgroundTwo species of wild silkworms, the Chinese oak silkworm (Antheraea pernyi) and the castor silkworm Philosamia cynthia ricini, can acquire a serious disease caused by Nucleopolyhedrin Viruses (NPVs) (known as AnpeNPV and PhcyNPV, respectively). The two viruses have similar polyhedral morphologies and their viral fragments share high sequence similarity. However, the physical maps of the viral genomes and cross-infectivity of the viruses are different. The genome sequences of two AnpeNPV isolates have been published.ResultsWe sequenced and analyzed the full-length genome of PhcyNPV to compare the gene contents of the two viruses. The genome of PhcyNPV is 125, 376 bp, with a G + C content of 53.65%, and encodes 138 open reading frames (ORFs) of at least 50 amino acids (aa) (GenBank accession number: JX404026). Between PhcyNPV and AnpeMNPV-L and -Z isolates, 126 ORFs are identical, including 30 baculovirus core genes. Nine ORFs were only found in PhcyNPV. Four genes, cath, v-chi, lef 10 and lef 11, were not found in PhcyNPV. However, most of the six genes required for infectivity via the oral route were found in PhcyNPV and in the two AnpeNPV isolates, with high sequence similarities. The pif-3 gene of PhcyNPV contained 59 aa extra amino acids at the N-terminus compared with AnpeNPV.ConclusionsMost of the genes in PhcyNPV are similar to the two AnpeNPV isolates, including the direction of expression of the ORFs. Only a few genes were missing from PhcyNPV. These data suggest that PhcyNPV and AnpeNPV might be variants of each other, and that the differences in cross-infection might be caused by gene mutations.

Transcriptome Analysis Reveals Potential Antioxidant Defense Mechanisms in Antheraea pernyi in Response to Zinc Stress

“…Furthermore, A. pernyi is now used as a model organism for a variety of research purposes because of the ease of its rearing and experimental manipulation compared with other lepidopteran insects. However, the health and vigor of A. pernyi are threatened by numerous parasites and pathogens, including viruses, mites, bacteria, and protozoans . In addition, the growth and development of larva are also strongly affected by environmental conditions, including heavy metal pollution, climate, foliage, and diseases …”

A chromosome‐scale genome assembly of Antheraea pernyi (Saturniidae, Lepidoptera)

“…Previous studies on A. pernyi have primarily focused on cloning and functional analysis of certain structural or stress‐related protein‐coding genes (Liu et al., 2014; Liu, Liu, et al., 2018; Liu, Xin, et al., 2018; Liu, Xin, et al., 2018; Liu, You, et al., 2014; Sezutsu & Yukuhiro, 2000; Yukuhiro, Kanda, & Tamura, 1997; Zhang et al., 2015), along with investigating its role in nucleopolyhedrovirus infection (Liu, Wang, et al., 2019; Qian et al., 2013; Sun et al., 2017; Wang, Na, Duan, et al., 2019; Wang, Na, & Qin, 2019; Zhang, Zhu, Dai, L. Liu, & Luo, 2016), and the nature of the silk fibre (Silva, Kundu, Lu, Reis, & Kundu, 2019; Suzuki, Chirila, & Edwards, 2016; Zhang, Yang, Shao, & Hu, 2010). These studies identified a few key genes, along with providing some insights into the characteristics of viral infection and the properties of natural silk.…”

The complete mitochondrial genome and phylogenetic analysis of the Philosamia cynthia ricini 754

“…The Eri-silkworm, Philosamia cynthia ricini, a wild silkworm belong to Saturniidae, Attacinae, Philosamia, cynthia, ricini, is native to the Assam Forest in northeastern India (Qian et al 2013), and was introduced into China for silk production in the 1950s (Liu et al 2010). It is a completely metamorphosed, without diapauses insect, and can be adapted to high temperature and high humidity environment.…”