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X69R Is a Non-Essential Gene That, When Deleted from African Swine Fever, Does Not Affect Virulence in Swine.

ABSTRACT: African swine fever virus (ASFV) is currently causing devastating outbreaks in Asia and Europe, and the ASFV strain Georgia (ASFV-G) is responsible for these outbreaks. ASFV-G is highly virulent and continues to be maintained in these outbreak areas, apparently without suffering significant genomic or phenotypic changes. When comparing the genome of ASFV-G to other isolates, a thus-far uncharacterized gene, X69R, is highly conserved and, interestingly, is similar to another ASFV uncharacterized gene, J64R. All sequenced ASFV isolates have one or both of these genes, X69R or J64R, suggesting that the presence of at least one of these genes may be necessary for ASFV replication and or virulence. The X69R gene is present in the ASFV-G genome while J64R is absent. To assess the importance of X69R in ASFV-G functionality, we developed a recombinant virus by deleting the X69R gene from the ASFV-G genome (ASFV-G-?X69R). ASFV-G-?X69R had the same replication kinetics in primary swine macrophage cultures as the parental ASFV-G, indicating that the X69R gene is not essential for ASFV-G viability or efficient replication in the main target cell during in vivo infection. In addition, swine intramuscularly inoculated with a low dose (102 HAD50) of ASFV-G-?X69R developed a clinical disease indistinguishable from that induced by the same dose of the virulent parental ASFV-G isolate. Viremia values of ASFV-G-?X69R did not significantly differ from those detected in animals infected with parental virus. Therefore, deletion of the X69R gene from ASFV-G does not affect virus replication or virulence in swine.

SUBMITTER: Ramirez-Medina E

PROVIDER: S-EPMC7551905 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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X69R Is a Non-Essential Gene That, When Deleted from African Swine Fever, Does Not Affect Virulence in Swine.

Ramirez-Medina Elizabeth E Vuono Elizabeth E Pruitt Sarah S Rai Ayushi A Silva Ediane E Zhu James J Velazquez-Salinas Lauro L Gladue Douglas P DP Borca Manuel V MV

Viruses 20200821 9

African swine fever virus (ASFV) is currently causing devastating outbreaks in Asia and Europe, and the ASFV strain Georgia (ASFV-G) is responsible for these outbreaks. ASFV-G is highly virulent and continues to be maintained in these outbreak areas, apparently without suffering significant genomic or phenotypic changes. When comparing the genome of ASFV-G to other isolates, a thus-far uncharacterized gene, X69R, is highly conserved and, interestingly, is similar to another ASFV uncharacterized ...[more]

PMID: 32825617

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Dataset Information

X69R Is a Non-Essential Gene That, When Deleted from African Swine Fever, Does Not Affect Virulence in Swine.

Publications

X69R Is a Non-Essential Gene That, When Deleted from African Swine Fever, Does Not Affect Virulence in Swine.

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