InterPro: IPR012344 Matrix protein, N-terminal, lentiviral and alpha-retroviral

Retroviral matrix proteins (or major core proteins) are components of envelope-associated capsids, which line the inner surface of virus envelopes and are associated with viral membranes [1]. Matrix proteins are produced as part of Gag precursor polyproteins. During viral maturation, the Gag polyprotein is cleaved into major structural proteins by the viral protease, yielding the matrix (MA), capsid (CA), nucleocapsid (NC), and some smaller peptides. Gag-derived proteins govern the entire assembly and release of the virus particles, with matrix proteins playing key roles in Gag stability, capsid assembly, transport and budding. Although matrix proteins from different retroviruses appear to perform similar functions and can have similar structural folds, their primary sequences can be very different.

This entry represents matrix proteins from primate lentiviruses, such as human and simian immunodeficiency viruses (HIV and SIV, respectively), equine lentiviruses, such as Equine infectious anemia virus (EIAV), and avian alpha-retroviruses such as Rous sarcoma virus (RSV), and type C retroviruses, such as Avian sarcoma virus, respectively [2, 3, 4]. This entry also identifies matrix proteins from several eukaryotic endogenous retroviruses, which arise when one or more copies of the retroviral genome becomes integrated into the host genome [5].