Penzo Carlotta, Özel Ilayda, Martinovic Moreno, Kuzman Maja, Glavas Dunja, Stanic Mia, Reichenbach Thomas, Müller Thorsten G, Rheinberger Mona, Godarzi Negar, Lapaillerie Delphine, Srezovic Bruno, dell'Oca Maria Chiara, Lange Laura C, Sadhu Lopamudra, de Castro Ines J, Shytaj Iart Luca, Forcato Mattia, Laketa Vibor, Bicciato Silvio, Vlahovicek Kristian, Fackler Oliver T, Lucic Bojana, Pena Vlad, Kräusslich Hans-Georg, Parissi Vincent, Lusic Marina
Department of Infectious Diseases, Center for Integrative Infectious Disease Research (CIID), Integrative Virology, Heidelberg University, Heidelberg, Germany.
Translational Neuroblastoma Research, German Cancer Research Center (DKFZ) and the Hopp Children's Cancer Center (KiTZ), Heidelberg, Germany.
Nat Microbiol. 2025 Aug 20. doi: 10.1038/s41564-025-02089-2.
HIV-1 integration into host chromosomes, essential for viral replication, is catalysed by viral integrase (IN). IN recurrently targets intronic regions of transcriptionally active genes, but a detailed understanding of this process is still unclear. Here, using ex vivo activated human primary CD4T cells, we find that genomic RNA:DNA hybrids (R-loops) preferentially map to intronic regions of active genes that are typical HIV-1 integration sites. IN binds R-loops and their resolution enhances viral integration in vitro. We identify Aquarius (AQR), the splicing RNA helicase of the pentameric intron binding complex (IBC), which associates with IN and show that its RNA:DNA helicase activity promotes integration into hybrid substrates in vitro. Knockout of AQR in primary CD4 T cells impaired overall integration efficiency, while sequencing of remaining integrations mapped them to intergenic and R-loop distal regions. These findings may have important implications for HIV-1 latency and reactivation and may thus identify novel therapeutic targets.
HIV-1整合到宿主染色体中是病毒复制所必需的，这一过程由病毒整合酶（IN）催化。IN反复靶向转录活跃基因的内含子区域，但对这一过程的详细了解仍不清楚。在这里，我们使用体外激活的人类原代CD4 T细胞，发现基因组RNA:DNA杂交体（R环）优先定位于活跃基因的内含子区域，这些区域是典型的HIV-1整合位点。IN结合R环，其解析增强了体外病毒整合。我们鉴定出水瓶座（AQR），它是五聚体内含子结合复合物（IBC）的剪接RNA解旋酶，与IN相关，并表明其RNA:DNA解旋酶活性促进体外整合到杂交底物中。原代CD4 T细胞中AQR的敲除损害了整体整合效率，而对剩余整合的测序将它们定位到基因间和R环远端区域。这些发现可能对HIV-1潜伏和重新激活具有重要意义，因此可能确定新的治疗靶点。
