Gag-onc fusion protein

Gag genes are part of a general architecture for retroviruses, viruses that replicate through reverse transcription, where the gag region of the genome encodes proteins that constitute the matrix, capsid and nucleocapsid of the mature virus particles. Like in HIV's replication cycle, these proteins are needed for viral budding from the host cell's plasma membrane, where the fully formed virions leave the cell to infect other cells. ==gag-v-onc==

When a viral gene is introduced into the host cell and is sufficient to induce oncogenesis – the creation of cancerous cells – in the infected cell line, the gene is said to be a "viral transforming gene". When this type of gene is translated to a protein, the protein is called a "transforming protein". Note that since the viral oncogenes originated from a host genome, the transformation event is different from transduction, which describes the process of introducing non-native genes to a host organism via a viral infection. Rous sarcoma virus The Gag-v-Onc fusion protein from the Rous sarcoma virus illustrates the dual role that the fusion protein plays in the viral and host cellular life cycle. For example, the viral gene Src (as in "sarcoma") is not necessary for viral reproduction, but does affect virulence. Due to evidence of conserved homology between the v-Src gene and its host (animal) genomes, and its non-essential status for viral reproduction, the v-Src gene is likely to have been acquired from a host genome and altered by subsequent mutations. ==See also==