The Complete Genome of an Endogenous Nimavirus (<i>Nimav-1_LVa</i>) From the Pacific Whiteleg Shrimp <i>Penaeus</i> (<i>Litopenaeus</i>) <i>Vannamei</i>

• Main Authors: Weidong Bao, Kathy F. J. Tang, Acacia Alcivar-Warren
• Format: Article
• Language: English
• Published: MDPI AG 2020-01-01
• Series: Genes
• Subjects: wssv; white spot syndrome virus; <i>nimaviridae</i>; <i>nimav-1_lva</i>; <i>dnav-1_lva</i>; <i>penaeus</i> (<i>litopenaeus</i>) <i>vannamei</i>
• Online Access: https://www.mdpi.com/2073-4425/11/1/94

White spot syndrome virus (WSSV), the lone virus of the genus <i>Whispovirus</i> under the family <i>Nimaviridae</i>, is one of the most devastating viruses affecting the shrimp farming industry. Knowledge about this virus, in particular, its evolution history, has been limited, partly due to its large genome and the lack of other closely related free-living viruses for comparative studies. In this study, we reconstructed a full-length endogenous nimavirus consensus genome, <i>Nimav-1_LVa</i> (279,905 bp), in the genome sequence of <i>Penaeus</i> (<i>Litopenaeus</i>) <i>vannamei</i> breed Kehai No. 1 (ASM378908v1). This endogenous virus seemed to insert exclusively into the telomeric pentanucleotide microsatellite (TAACC/GGTTA)_n. It encoded 117 putative genes, with some containing introns, such as <i>g012</i> (inhibitor of apoptosis, IAP), <i>g046</i> (crustacean hyperglycemic hormone, CHH), <i>g155</i> (innexin), <i>g158</i> (Bax inhibitor 1 like). More than a dozen <i>Nimav-1_LVa</i> genes are involved in the pathogen-host interactions. We hypothesized that <i>g046</i>, <i>g155</i>, <i>g158,</i> and <i>g227</i> (semaphorin 1A like) were recruited host genes for their roles in immune regulation. Sequence analysis indicated that a total of 43 WSSV genes belonged to the ancestral/core nimavirus gene set, including four genes reported in this study: wsv112 (dUTPase), wsv206, wsv226, and wsv308 (nucleocapsid protein). The availability of the <i>Nimav-1_LVa</i> sequence would help understand the genetic diversity, epidemiology, evolution, and virulence of WSSV.