Protein Domain : Beta-retroviral matrix superfamily IPR038124

Type	Homologous_superfamily
Description	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 [ ]. 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 which predominantly consist of four closely packed α-helices that are interconnected through loops, their primary sequences can be very different []. This entry represents matrix proteins from beta-retroviruses such as Mason-Pfizer monkey virus (MPMV) (Simian Mason-Pfizer virus) and Mouse mammary tumor virus (MMTV) [ , , ]. 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 [].
Short Name	B_retro_matrix_sf