Spumavirus
Encyclopedia
A spumavirus or foamyvirus is a genus
of the retroviridae family
. Spumaviruses are exogenous
viruses that have specific morphology
with prominent surface spikes
. The virions contain significant amounts of double-stranded full-length DNA
, and assembly is rather unusual in these viruses. Supumaviruses are unlike most enveloped viruses in that the envelope
membrane is acquired by budding
through the endoplasmic reticulum
instead of the cytoplasmic membrane. Some spumaviruses, including the equine foamy virus (EFV), bud from the cytoplasmic membrane.
Some examples of this virus are the chimpanzee foamy virus, simian foamy virus
and the human foamy virus
.
While spumaviruses will form characteristic large vacuoles in their host cells while in vitro, there is no disease association in vivo.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of the retroviridae family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
. Spumaviruses are exogenous
Exogenous
Exogenous refers to an action or object coming from outside a system. It is the opposite of endogenous, something generated from within the system....
viruses that have specific morphology
Morphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
with prominent surface spikes
Peplomer
A peplomer is a glycoprotein spike on a viral capsid or viral envelope. These protrusions will only bind to certain receptors on the host cell: they are essential for both host specificity and viral infectivity...
. The virions contain significant amounts of double-stranded full-length DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...
, and assembly is rather unusual in these viruses. Supumaviruses are unlike most enveloped viruses in that the envelope
Viral envelope
Many viruses have viral envelopes covering their protein capsids. The envelopes typically are derived from portions of the host cell membranes , but include some viral glycoproteins. Functionally, viral envelopes are used to help viruses enter host cells...
membrane is acquired by budding
Budding
Budding is a form of asexual reproduction in which a new organism grows on another one. The new organism remains attached as it grows, separating from the parent organism only when it is mature. Since the reproduction is asexual, the newly created organism is a clone and is genetically identical...
through the endoplasmic reticulum
Endoplasmic reticulum
The endoplasmic reticulum is an organelle of cells in eukaryotic organisms that forms an interconnected network of tubules, vesicles, and cisternae...
instead of the cytoplasmic membrane. Some spumaviruses, including the equine foamy virus (EFV), bud from the cytoplasmic membrane.
Some examples of this virus are the chimpanzee foamy virus, simian foamy virus
Simian foamy virus
The simian foamy virus is a spumavirus closely related to the Human Immunodeficiency Virus, HIV, the virus that can lead to AIDS. Its discovery in primates has led to some speculation that HIV may have been spread to the human species in Africa through contact with blood from apes, monkeys, and...
and the human foamy virus
Human foamy virus
Human Foamy Virus is a retrovirus and specifically belongs to the genera Spumavirus. The spumaviruses are complex and significantly different from the other six genera or retroviruses in several ways...
.
While spumaviruses will form characteristic large vacuoles in their host cells while in vitro, there is no disease association in vivo.
Further reading
- Santillana-Hayat M, Valla J et al. "Inhibition of the in vitro infectivity and cytopathic effect of human foamy virus by dideoxynucleosides". AIDS Res Hum Retroviruses. 1996 Oct 10; 12(15):1485-90.