%0 Journal Article
%T HIV-2 inhibits HIV-1 gene expression via two independent mechanisms during cellular co-infection.
%A Yapo V
%A Majumder K
%A Tedbury PR
%A Wen X
%A Ong YT
%A Johnson MC
%A Sarafianos SG
%J J Virol
%V 97
%N 12
%D 2023 Dec 21
%M 37991365
%F 6.549
%R 10.1128/jvi.01870-22
%X <B>OBJECTIVE: </B>Twenty-five years after the first report that HIV-2 infection can reduce HIV-1-associated pathogenesis in dual-infected patients, the mechanisms are still not well understood. We explored these mechanisms in cell culture and showed first that these viruses can co-infect individual cells. Under specific conditions, HIV-2 inhibits HIV-1 through two distinct mechanisms, a broad-spectrum interferon response and an HIV-1-specific inhibition conferred by the HIV-2 TAR. The former could play a prominent role in dually infected individuals, whereas the latter targets HIV-1 promoter activity through competition for HIV-1 Tat binding when the same target cell is dually infected. That mechanism suppresses HIV-1 transcription by stalling RNA polymerase II complexes at the promoter through a minimal inhibitory region within the HIV-2 TAR. This work delineates the sequence of appearance and the modus operandi of each mechanism.