Alvernaviridae

Alvernaviridae is a family of RNA viruses that infects marine dinoflagellates. This family is characterized by its single-stranded, positive-sense RNA genome. The family contains a single genus, Alvernavirus, and a single species, Heterocapsa circularisquama RNA virus 01 (HcRNAV01).

Discovery and Classification

The family Alvernaviridae was first described in 2012 following the isolation and characterization of a virus infecting the marine dinoflagellate Heterocapsa circularisquama. This virus was named Heterocapsa circularisquama RNA virus 01 (HcRNAV01) and became the type species of the family.

Genome and Structure

The genome of Alvernaviridae is a single-stranded, positive-sense RNA molecule approximately 4.4 kilobases in length. The genome encodes a single open reading frame (ORF) that is translated into a polyprotein, which is subsequently cleaved into functional viral proteins. The virions are non-enveloped and have an icosahedral symmetry with a diameter of about 30 nm.

Replication Cycle

The replication cycle of Alvernaviridae begins with the attachment of the virus to the host cell surface, followed by entry into the host cell. Once inside, the viral RNA is released into the cytoplasm, where it serves as a template for translation of viral proteins. The replication of the viral genome occurs in the cytoplasm, and new virions are assembled and released from the host cell, often resulting in cell lysis.

Host and Ecology

Alvernaviridae viruses specifically infect marine dinoflagellates, particularly Heterocapsa circularisquama. These viruses play a significant role in the regulation of dinoflagellate populations in marine ecosystems, potentially influencing algal bloom dynamics.

Significance

Understanding the biology and ecology of Alvernaviridae is important for marine biology and ecology, as these viruses can impact the population dynamics of dinoflagellates, which are key components of marine food webs and can cause harmful algal blooms.

Also see

• Dinoflagellate
• RNA virus
• Viral replication
• Marine virology