Résumé : In addition to the classical cis-regulatory elements located in the Human Immunodeficiency virus type 1 (HIV-1) 5’ long terminal repeat (5’LTR), our laboratory has identified an important intragenic cis-regulatory region (IRR) that presents enhancer activity and from which transcription arises. This project aims at further studying how differential occupation of transcription factor binding sites (TFBS) in different cellular environments of infection affects the IRR enhancer activity, and at determining the nature and biological role of HIV-1 intragenic transcription.