Mediates, with Gag polyprotein, the essential events in virion assembly, including binding the plasma membrane, making the protein-protein interactions necessary to create spherical particles, recruiting the viral Env proteins, and packaging the genomic RNA via direct interactions with the RNA packaging sequence (Psi). Gag-Pol polyprotein may regulate its own translation, by the binding genomic RNA in the 5'-UTR. At low concentration, the polyprotein would promote translation, whereas at high concentration, the polyprotein would encapsidate genomic RNA and then shut off translation. Targets the polyprotein to the plasma membrane via a multipartite membrane-binding signal, that includes its myristoylated N-terminus. Matrix protein is part of the pre-integration complex. Implicated in the release from host cell mediated by Vpu. Binds to RNA. Forms the conical core that encapsulates the genomic RNA-nucleocapsid complex in the virion. Most core are conical, with only 7% tubular. The core is constituted by capsid protein hexamer subunits. The core is disassembled soon after virion entry (By similarity). Host restriction factors such as TRIM5-alpha or TRIMCyp bind retroviral capsids and cause premature capsid disassembly, leading to blocks in reverse transcription. Capsid restriction by TRIM5 is one of the factors which restricts HIV-1 to the human species. Host PIN1 apparently facilitates the virion uncoating. On the other hand, interactions with PDZD8 or CYPA stabilize the capsid. Encapsulates and protects viral dimeric unspliced genomic RNA (gRNA). Binds these RNAs through its zinc fingers. Acts as a nucleic acid chaperone which is involved in rearangement of nucleic acid secondary structure during gRNA retrotranscription. Also facilitates template switch leading to recombination. As part of the polyprotein, participates in gRNA dimerization, packaging, tRNA incorporation and virion assembly. Aspartyl protease that 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. Also cleaves Nef and Vif, probably concomitantly with viral structural proteins on maturation of virus particles. Hydrolyzes host EIF4GI and PABP1 in order to shut off the capped cellular mRNA translation. The resulting inhibition of cellular protein synthesis serves to ensure maximal viral gene expression and to evade host immune response. Also mediates cleavage of host YTHDF3. Mediates cleavage of host CARD8, thereby activating the CARD8 inflammasome, leading to the clearance of latent HIV-1 in patient CD4(+) T-cells after viral reactivation; in contrast, HIV-1 can evade CARD8-sensing when its protease remains inactive in infected cells prior to viral budding (By similarity). Specific for a P1 residue that is hydrophobic, and P1' variable, but often Pro. The viral protease is inhibited by many synthetic protease inhibitors (PIs), such as amprenavir, atazanavir, indinavir, loprinavir, nelfinavir, ritonavir and saquinavir. Use of protease inhibitors in tritherapy regimens permit more ambitious therapeutic strategies. Homotrimer; further assembles as hexamers of trimers (By similarity). Interacts with gp41 (via C-terminus) (By similarity). Interacts with host CALM1; this interaction induces a conformational change in the Matrix protein, triggering exposure of the myristate group (By similarity). Interacts with host AP3D1; this interaction allows the polyprotein trafficking to multivesicular bodies during virus assembly (By similarity). Part of the pre-integration complex (PIC) which is composed of viral genome, matrix protein, Vpr and integrase (By similarity). Homodimer; the homodimer further multimerizes as homohexamers or homopentamers. Interacts with human PPIA/CYPA (By similarity); This interaction stabilizes the capsid. Interacts with human NUP153 (By similarity). Interacts with host PDZD8; this interaction stabilizes the capsid (By similarity). Interacts with monkey TRIM5; this interaction destabilizes the capsid (By similarity). Homodimer, whose active site consists of two apposed aspartic acid residues. These locations are linked to virus assembly sites. The main location is the cell membrane, but under some circumstances, late endosomal compartments can serve as productive sites for virion assembly. Translation results in the formation of the Gag polyprotein most of the time. Ribosomal frameshifting at the gag-pol genes boundary occurs at low frequency and produces the Gag-Pol polyprotein. This strategy of translation probably allows the virus to modulate the quantity of each viral protein. Maintenance of a correct Gag to Gag-Pol ratio is essential for RNA dimerization and viral infectivity. Specific enzymatic cleavages by the viral protease yield mature proteins. The protease is released by autocatalytic cleavage. The polyprotein is cleaved during and after budding, this process is termed maturation. Proteolytic cleavage of p66 RT removes the RNase H domain to yield the p51 RT subunit. Nucleocapsid protein p7 might be further cleaved after virus entry (By similarity). Tyrosine phosphorylated presumably in the virion by a host kinase. Phosphorylation is apparently not a major regulator of membrane association. Phosphorylated possibly by host MAPK1; this phosphorylation is necessary for Pin1-mediated virion uncoating. Methylated by host PRMT6, impairing its function by reducing RNA annealing and the initiation of reverse transcription. HIV-1 lineages are divided in three main groups, M (for Major), O (for Outlier), and N (for New, or Non-M, Non-O). The vast majority of strains found worldwide belong to the group M. Group O seems to be endemic to and largely confined to Cameroon and neighboring countries in West Central Africa, where these viruses represent a small minority of HIV-1 strains. The group N is represented by a limited number of isolates from Cameroonian persons. The group M is further subdivided in 9 clades or subtypes (A to D, F to H, J and K). Resistance to inhibitors associated with mutations are observed both in viral protease and in reverse transcriptase. Most of the time, single mutations confer only a modest reduction in drug susceptibility. Combination of several mutations is usually required to develop a high-level drug resistance. These mutations are predominantly found in clade B viruses and not in other genotypes. They are listed in the clade B representative isolate HXB2 (AC P04585). Produced by -1 ribosomal frameshifting. HIV drug resistance database