An African Swine Fever Virus ERV1-ALR Homologue, 9GL , Affects Virion Maturation and Viral Growth in Macrophages and Viral Virulence in Swine

Abstract

The African swine fever virus (ASFV) genome contains a gene, 9GL, with similarity to yeast ERV1 and ALR genes. ERV1 has been shown to function in oxidative phosphorylation and in cell growth, while ALR has hepatotrophic activity. 9GL encodes a protein of 119 amino acids and was highly conserved at both nucleotide and amino acid levels among all ASFV field isolates examined.

Related strains of African swine fever virus with different virulence: genome comparison and analysis

“…Also in the CCR, pB119L viral thiol oxidase, pI215L ubiquitin-conjugating enzyme and pCP312R of unknown function all contain nonconservative aa substitutions that are exclusive to OURT88/ 3 and NHV. B119L is necessary for correct virion maturation and replication in macrophages, and its deletion from Malawi Lil-20/1 led to attenuation in swine (Lewis et al, 2000). The aa substitutions in both pB119L and pI215L are located outside their functional domains, but it is possible that they alter the protein structure, interfering with its function in low-virulence strains.…”

Cloning, expression and subcellular distribution of a Rana grylio virus late gene encoding ERV1 homologue

“…Interestingly, a GXXXW motif was found existed in all ERV1 homologues in our alignment. This motif also existed in ERV1 homologue from ASFV [16], but function of this motif remains unknown. ERV1 homologues are widespread in nature, but the evolutionary position of these homologues remains unknown.…”

“…However, RGV 88R was not distributed in viromatrix which is a factory for viral genome replication and particle assembly [32]. It revealed that 88R protein might not be a structural protein in RGV, and Lewis et al has confirmed that a ERV1 homologue, 9GL, existed in African swine fever virus was also a late protein but not a structural protein [16]. In general, late genes of large DNA virus encode mainly structural proteins.…”

“…(iii) Other homologue of 88R may exist in the RGV genome that able to circumvent its function. And knockout ERV1 homologue in ASFV affects viral growth in vitro and viral virulence in vivo [16]. Consequently, gene knockout techniques may be needed to understand RGV 88R function in further studies.…”

“…These homologues are multifunctional, performing roles in DNA replication, protein synthesis, protein folding, and photosynthesis [14]. Interestingly, ERV1 gene homologues are present in a number of other DNA viruses, including poxvirus, chlorella virus, and African swine fever virus [15,16].…”