Deciphering the molecular mechanisms of hiv dna nuclear import and the impact of 3d genome organization on integration site selection
Chromosomes of eukaryotes adopt highly dynamic and complex hierarchical structures in the nucleus. The three-dimensional (3D) organization of chromosomes profoundly affects DNA functions, primarily transcription. During retroviral infection, histone-free viral DNA copy is synthesized from viral genomic RNA. vDNA will ultimately integrate into the host genome to ensure its maintenance and expression.  Understanding retrovirus-host interactions at the genomic level, and the peculiar mechanisms by which lentiviruses, including HIV-1, and their related gene transfer vectors, are imported into the nucleus, loaded with nucleosomes, integrate in, and interact with, the human genome will provide valuable information about lentiviral replication and establish the basis for the development of safer and more efficacious lentiviral vectors for human gene therapy. Our objectives are: 1-To identify and characterize cellular proteins associated with the HIV-1 PIC, and determine their roles in nuclear import and/or integration. 2-To explore the role of the epigenome of unintegrated vDNA in HIV-1 gene expression from unintegrated and integrated vDNA. 3- To determine the impact of nuclear organization on integration site selection and on viral and host transcription. State of the art technologies will be applied to achieve these challenging objectives. If successful, this project will make an outstanding contributions not only to the field of HIV biology but also for the development of safe lentiviral vectors for gene therapy.