EF1α-iCre-Puro Lentivirus

To efficiently transduce a target cell, the lentiviral genome is composed of the following coding genes: Gag encoding for matrix (MA), nucleocapsid (NC), capsid (CA), and p6 proteins required for viral assembly and infection; Pol encoding for reverse transcriptase (RT), RNase H, protease (PRO), and integrase (IN), essential for reverse transcription and genomic integration; Env encoding for surface glycoproteins (SU, TM) that define tropism of the virus and enable entry into the host cells; Tat and Rev, two regulatory genes that activate viral transcription and nuclear export of intron-containing nascent viral RNA, respectively; Four accessory genes, Vif, Vpr, Vpu, and Nef; Several cis-acting elements are also critical for viral replication, such as ψ, the packaging signal; RRE, the Rev response element, is required for the processing and transport of viral RNAs; cPPT/CTS, the central polypurine tract, and the central termination sequence, whose role is still questioned, suspected to be linked to nuclear transport and replication; TAR, the TAT activation region; The splicing donor (SD) and acceptor (SA) sites, which allow the production of all viral proteins and the viral RNA starting from a unique pre-mRNA. The insertion of the viral genome into the host genome follows the subsequent steps:(1) binding to the host cell, membrane fusion, and entry of the capsid, (2) reverse transcription of the viral RNA into DNA, (3) nuclear import, and (4) provirus integration. The uncoating of the capsid is still not clear as CA was shown to influence reverse transcription, nuclear import, and provirus integration.