Semliki Forest virus

Semliki Forest virus (SFV) is a species of virus in the family Togaviridae, and the genus Alphavirus. It was first isolated in 1942 from mosquitoes in the Semliki Forest, Uganda, from which it derives its name. SFV is an Arbovirus, meaning it is transmitted by Arthropod vectors, specifically mosquitoes.

Structure and Genome

SFV is an enveloped virus with an icosahedral symmetry. Its genome is a single-stranded, positive-sense RNA approximately 11.5 kilobases in length. The genome encodes four non-structural proteins (nsP1, nsP2, nsP3, and nsP4) and five structural proteins (C, E1, E2, E3, and 6K).

Life Cycle

The life cycle of SFV begins when the virus is taken up by a host cell through receptor-mediated endocytosis. The virus then uncoats and releases its RNA genome into the cytoplasm of the host cell. The RNA is translated into a polyprotein, which is cleaved into individual proteins by viral proteases. These proteins then assemble into new virus particles, which are released from the host cell by budding.

Pathogenesis and Immunity

SFV primarily infects rodents and birds, but can also infect humans, causing a mild febrile illness. The virus is neurotropic, meaning it has a preference for infecting nerve cells. Infection with SFV stimulates a strong immune response, with the production of neutralizing antibodies and T cells.

Research Applications

SFV has been widely used as a model organism in virology research, particularly in studies of virus-host interactions and viral pathogenesis. It has also been used as a vector for gene therapy and vaccine development.

See Also

• Alphavirus
• Arbovirus
• Togaviridae
• Virology