''Spumaretrovirinae'', commonly called spumaviruses (,

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

for "foam") or foamyviruses, is a subfamily of the ''

Retroviridae A retrovirus is a type of virus that inserts a DNA copy of its RNA genome into the DNA of a host cell that it invades, thus changing the genome of that cell. Once inside the host cell's cytoplasm, the virus uses its own reverse transcriptase e ...

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

. ICTV
Master Species List 2018a v1
MSL including all taxa updates since the 2017 release. Fall 2018 (MSL #33) Spumaviruses are

exogenous In a variety of contexts, exogeny or exogeneity () is the fact of an action or object originating externally. It contrasts with endogeneity or endogeny, the fact of being influenced within a system. Economics In an economic model, an exogeno ...

viruses that have specific

morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines * Morphology (archaeology), study of the shapes or forms of artifacts * Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies ...

with prominent surface

spikes The SPIKES protocol is a method used in clinical medicine to break bad news to patients and families. As receiving bad news can cause distress and anxiety, clinicians need to deliver the news carefully. By using the SPIKES method for introducing a ...

. The

virions A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Since Dmitri Ivanovsky's ...

contain significant amounts of double-stranded full-length DNA, and assembly is rather unusual in these viruses. Spumaviruses are unlike most enveloped viruses in that the

envelope An envelope is a common packaging item, usually made of thin, flat material. It is designed to contain a flat object, such as a letter or card. Traditional envelopes are made from sheets of paper cut to one of three shapes: a rhombus, a shor ...

membrane is acquired by

budding Budding or blastogenesis is a type of asexual reproduction in which a new organism develops from an outgrowth or bud due to cell division at one particular site. For example, the small bulb-like projection coming out from the yeast cell is know ...

through the

endoplasmic reticulum The endoplasmic reticulum (ER) is, in essence, the transportation system of the eukaryotic cell, and has many other important functions such as protein folding. It is a type of organelle made up of two subunits – rough endoplasmic reticulum ( ...

instead of the

cytoplasmic membrane The cell membrane (also known as the plasma membrane (PM) or cytoplasmic membrane, and historically referred to as the plasmalemma) is a biological membrane that separates and protects the interior of all cells from the outside environment ( ...

. Some spumaviruses, including the equine foamy virus (EFV), bud from the cytoplasmic membrane. Some examples of these viruses are

simian foamy virus ''Simian foamy virus'' (''SFV'') is a species of the genus ''Spumavirus'' that belongs to the family of ''Retroviridae''. It has been identified in a wide variety of primates, including prosimians, New World and Old World monkeys, as well as ap ...

and the

human foamy virus Human foamy virus (HFV) is a retrovirus and specifically belongs to the genus ''Spumavirus''. The spumaviruses are complex and significantly different from the other six genera of retroviruses in several ways. The foamy viruses derive their na ...

. While spumaviruses will form characteristic large vacuoles in their host cells while ''in vitro'', there is no disease association ''in vivo''.

References

External links

* *
Viralzone: "Spumavirus"
{{virus-stub Spumaviruses de:Spumaviren es:Spumavirus

References

Further reading

External links