UMR Inserm U944-CNRS, université Paris-Diderot, Institut universitaire d’hématologie, 1, avenue Claude-Vellefaux, 75475 Paris Cedex 10, Conservatoire national des arts et métiers, Chaire de biologie, 2, rue Conté, 75003 Paris
Many cellular and viral proteins and nucleic acids shuttle between the nucleus and the cytoplasm. It is increasingly clear that nuclear import and export involve complex and finely regulated mechanisms. Nuclear export is absolutely necessary for viral protein synthesis and particle assembly for retroviruses showing a nuclear step during their replication cycle. Nuclear export of retroviral components mainly relies on two distinct mechanisms, one involving cellular factors only, and another in which cellular and viral factors cooperate. The study of retrovirus nuclear export contributes significantly to our understanding of the molecular mechanisms of nuclear export in general, and may allow the identification of new targets to prevent retrovirus replication.