TY - JOUR
T1 - CpG dinucleotides inhibit HIV-1 replication through zinc finger antiviral protein (ZAP)-dependent and -independent mechanisms)
AU - Ficarelli, Mattia
AU - Antzin Anduetza, Irati
AU - Hugh-White, Rupert Jacob
AU - Firth, Andrew
AU - Sertkaya, Helin
AU - Wilson, Harry David
AU - Neil, Stuart John Douglas
AU - Schulz, Reiner Sebastian David
AU - Swanson, Chad Michael
PY - 2020/2/28
Y1 - 2020/2/28
N2 - CpG dinucleotides are suppressed in the genomes of many vertebrate RNA viruses, including HIV-1. The cellular antiviral protein ZAP binds CpGs and inhibits HIV-1 replication when they are introduced in the viral genome. However, it is not known if ZAP-mediated restriction is the only mechanism driving CpG suppression. To determine how CpG dinucleotides affect HIV-1 replication, we increased their abundance in multiple regions of the viral genome and analyzed the effect on RNA expression, protein abundance and infectious virus production. We found that the antiviral effect of CpGs does not correlate with their abundance. Interestingly, CpGs inserted into some regions of the genome sensitize the virus to ZAP antiviral activity more efficiently than other regions and this sensitivity can be modulated by interferon treatment or ZAP overexpression. Furthermore, the sensitivity of the virus to endogenous ZAP correlated with its sensitivity to the ZAP cofactor KHNYN. Finally, we show that CpGs in some contexts can also inhibit HIV-1 replication by ZAP-independent mechanisms and one of these is the activation of a cryptic splice site at the expense of a canonical splice site. Overall, we show that the location and sequence context of the CpG in the viral genome determines its antiviral activity.
AB - CpG dinucleotides are suppressed in the genomes of many vertebrate RNA viruses, including HIV-1. The cellular antiviral protein ZAP binds CpGs and inhibits HIV-1 replication when they are introduced in the viral genome. However, it is not known if ZAP-mediated restriction is the only mechanism driving CpG suppression. To determine how CpG dinucleotides affect HIV-1 replication, we increased their abundance in multiple regions of the viral genome and analyzed the effect on RNA expression, protein abundance and infectious virus production. We found that the antiviral effect of CpGs does not correlate with their abundance. Interestingly, CpGs inserted into some regions of the genome sensitize the virus to ZAP antiviral activity more efficiently than other regions and this sensitivity can be modulated by interferon treatment or ZAP overexpression. Furthermore, the sensitivity of the virus to endogenous ZAP correlated with its sensitivity to the ZAP cofactor KHNYN. Finally, we show that CpGs in some contexts can also inhibit HIV-1 replication by ZAP-independent mechanisms and one of these is the activation of a cryptic splice site at the expense of a canonical splice site. Overall, we show that the location and sequence context of the CpG in the viral genome determines its antiviral activity.
M3 - Article
SN - 0022-538X
JO - Journal of virology
JF - Journal of virology
ER -