GSE184345
Multiomics profiling of HIV-infected cells
The restructuring of chromatin architecture following lentiviral integration is not well elucidated. We jointly interrogate (HIV-distal & -local) chromatin organization (via Hi-C & ATAC-seq) and the RNA landscape around defined sites of proviral integration using HIV-inducible cellular models. We report chromatin interaction networks and nuclear ultrastructure around integrated HIV-1 are predominantly preserved, suggesting HIV integration does not induce large scale remodeling of cellular chromatin. Instead, we find that induction of proviral transcription leads to stark local changes in nucleosome organization with chromatin accessibility increasing at the intergenic junction between the HIV-1 3' LTR and flanking cellular genome. This result suggests subtle changes in chromatin structure may be mediating proviral activation. Using long-read Nanopore RNA-seq, we interrogate the local host & HIV transcriptomes, observing a small fraction of HIV-1 transcripts are chimeric read-through products, where transcription initiates at the HIV-1 5' LTR promoter and continues extensively into the flanking cellular genome. Despite provirus-driven read-through, HIV-1 appears to have only a modest effect on the local transcriptional environment. The changes in chromatin accessibility and read-through at activated proviruses closely resembles lytic Herpes simplex virus type 1 (HSV-1) induced cellular chromatin reprogramming. We propose chromatin “opening” at the 3' LTR HIV-host junction is important for sustained proviral activity, and overall, HIV proviruses do not significantly alter local host transcription and chromatin structure. Our studies provide the first in-depth integrative investigation of 3D chromatin organization, nucleosome density, and HIV-host transcriptomes at HIV-host genic boundaries. Overall design: Chromatin and gene expression profiling at HIV-1 sites of integration in HIV-inactive -active states