InterPro domain: IPR000721

The Gag protein from retroviruses, also known as p24, forms the inner protein layer of thenucleocapsid. This protein performs highly complex orchestrated tasks during the assembly,budding, maturation and infection stages of the viral replication cycle. During viral assembly,the proteins form membrane associations and self-associations that ultimately result inbudding of an immature virion from the infected cell. Gag precursors also function duringviral assembly to selectively bind and package two plus strands of genomic RNA. ELISA testsfor p24 is the most commonly used method to demonstrate virus replication both in vivo and invitro .