Gag-Pro polyprotein: The matrix domain targets Gag, Gag-Pro and Gag-Pro-Pol polyproteins to the plasma membrane via a multipartite membrane binding signal, that includes its myristoylated N-terminus. Matrix protein. Forms the spherical core of the virus that encapsulates the genomic RNA-nucleocapsid complex. Binds strongly to viral nucleic acids and promote their aggregation. Also destabilizes the nucleic acids duplexes via highly structured zinc-binding motifs. The aspartyl protease mediates proteolytic cleavages of Gag and Gag-Pol polyproteins during or shortly after the release of the virion from the plasma membrane. Cleavages take place as an ordered, step-wise cascade to yield mature proteins. This process is called maturation. Displays maximal activity during the budding process just prior to particle release from the cell. RT is a multifunctional enzyme that converts the viral RNA genome into dsDNA in the cytoplasm, shortly after virus entry into the cell. This enzyme displays a DNA polymerase activity that can copy either DNA or RNA templates, and a ribonuclease H (RNase H) activity that cleaves the RNA strand of RNA-DNA heteroduplexes in a partially processive 3' to 5'-endonucleasic mode. Conversion of viral genomic RNA into dsDNA requires many steps. A tRNA-Pro binds to the primer-binding site (PBS) situated at the 5'-end of the viral RNA. RT uses the 3' end of the tRNA primer to perform a short round of RNA-dependent minus-strand DNA synthesis. The reading proceeds through the U5 region and ends after the repeated (R) region which is present at both ends of viral RNA. The portion of the RNA-DNA heteroduplex is digested by the RNase H, resulting in a ssDNA product attached to the tRNA primer. This ssDNA/tRNA hybridizes with the identical R region situated at the 3' end of viral RNA. This template exchange, known as minus-strand DNA strong stop transfer, can be either intra- or intermolecular. RT uses the 3' end of this newly synthesized short ssDNA to perform the RNA-dependent minus-strand DNA synthesis of the whole template. RNase H digests the RNA template except for a polypurine tract (PPT) situated at the 5' end of the genome. It is not clear if both polymerase and RNase H activities are simultaneous. RNase H probably can proceed both in a polymerase-dependent (RNA cut into small fragments by the same RT performing DNA synthesis) and a polymerase-independent mode (cleavage of remaining RNA fragments by free RTs). Secondly, RT performs DNA-directed plus-strand DNA synthesis using the PPT that has not been removed by RNase H as primer. PPT and tRNA primers are then removed by RNase H. The 3' and 5' ssDNA PBS regions hybridize to form a circular dsDNA intermediate. Strand displacement synthesis by RT to the PBS and PPT ends produces a blunt ended, linear dsDNA copy of the viral genome that includes long terminal repeats (LTRs) at both ends. Catalyzes viral DNA integration into the host chromosome, by performing a series of DNA cutting and joining reactions. a 2'-deoxyribonucleoside 5'-triphosphate + DNA(n) = diphosphate + DNA(n+1) a 2'-deoxyribonucleoside 5'-triphosphate + DNA(n) = diphosphate + DNA(n+1) Endonucleolytic cleavage to 5'-phosphomonoester. The RT polymerase active site binds 2 magnesium ions. Homodimer; the homodimers are part of the immature particles. Interacts with human TSG101 and NEDD4; these interactions are essential for budding and release of viral particles. Homodimer; further assembles as homohexamers. Gag polyprotein: Late-budding domains (L domains) are short sequence motifs essential for viral particle release. They can occur individually or in close proximity within structural proteins. They interacts with sorting cellular proteins of the multivesicular body (MVB) pathway. Most of these proteins are class E vacuolar protein sorting factors belonging to ESCRT-I, ESCRT-II or ESCRT-III complexes. Matrix protein p15 contains one L domain: a PPXY motif which binds to the WW domains of the ubiquitin ligase NEDD4. Phosphorylation of the matrix protein p15 by MAPK1 seems to play a role in budding. Myristoylated. Myristoylation of the matrix (MA) domain mediates the transport and binding of Gag polyproteins to the host plasma membrane and is required for the assembly of viral particles. Specific enzymatic cleavages by the viral protease yield mature proteins. The polyprotein is cleaved during and after budding, this process is termed maturation. The protease is autoproteolytically processed at its N- and C-termini. The reverse transcriptase is an error-prone enzyme that lacks a proof-reading function. High mutations rate is a direct consequence of this characteristic. RT also displays frequent template swiching leading to high recombination rate. Recombination mostly occurs between homologous regions of the two copackaged RNA genomes. If these two RNA molecules derive from different viral strains, reverse transcription will give rise to highly recombinated proviral DNAs. Produced by -1 ribosomal frameshiftings between gag-pro and pro-pol. Belongs to the retroviral Pol polyprotein family.