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Post by aqt on Jan 13, 2010 17:02:41 GMT -5
en.wikipedia.org/wiki/AlphavirusIn biology and immunology, an alphavirus belongs to the group IV Togaviridae family of viruses, according to the system of classification based on viral genome composition introduced by David Baltimore in 1971. Alphaviruses, like all other group IV viruses have a positive sense single stranded RNA genome. There are 27 alphaviruses, able to infect various vertebrates such as humans, rodents, birds, and larger mammals such as horses as well as invertebrates. Transmission between species and individuals occurs via mosquitoes making the alphaviruses a contributor to the collection of Arboviruses – or Arthropod Borne Viruses. Alphaviruses particles are enveloped have a 70 nm diameter, tend to be spherical (although slightly pleomorphic), and have a 40 nm isometric nucleocapsid.
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Post by aqt on Jan 13, 2010 17:13:24 GMT -5
Medically important alphaviruses Virus Human Disease Vertebrate Reservoir Distribution Sindbis virus Rash, arthritis Birds Europe, Africa, Australia Semliki Forest Virus Rash, arthritis Birds Africa O'nyong'nyong virus Rash, arthritis Primates, Humans Africa Chikungunya virus Rash, arthritis Primates, humans Africa, India, SE Asia Mayaro virus Rash, arthritis Primates, humans South America Ross River virus Rash, arthritis Mammals, humans Australia, South Pacific Barmah Forest virus Fever, malaise, rash, joint pain, muscle tenderness Humans Australia Eastern equine encephalitis virus Encephalitis Birds Americas Western equine encephalitis virus Encephalitis Birds, mammals North America Venezuelan equine encephalitis virus Encephalitis Rodents, horses Americas en.wikipedia.org/wiki/Alphavirus
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Post by aqt on Jan 13, 2010 17:20:08 GMT -5
Togaviridae en.wikipedia.org/wiki/TogaviridaeTogaviridae From Wikipedia, the free encyclopedia Jump to: navigation, search Togaviruses Virus classification Group: Group IV ((+)ssRNA) Family: Togaviridae Genera Alphavirus Rubivirus The Togaviridae are a family of viruses, including the following genera: Genus Alphavirus; type species: Sindbis virus, Eastern equine encephalitis virus, Western equine encephalitis virus, Venezuelan equine encephalitis virus, Ross River virus, O'nyong'nyong virus Genus Rubivirus; type species: Rubella virus The Togaviridae family belong to group IV of the Baltimore classification of viruses. The genome is linear, single-stranded, positive sense RNA that is 10,000-12,000 nucleotides long. The 5'-terminus carries a methylated nucleotide cap and the 3'-terminus has a polyadenylated tail, therefore resembling cellular mRNA. The virus is enveloped and forms spherical particles (65-70 nm diameter), the capsid within is icosahedral, constructed of 240 monomers, having a triangulation number of 4. The receptors for binding are unknown, however the tropism is varied and it is known that the glycoprotein spikes act as attachment proteins. After virus attachment and entry into the cell, gene expression and replication takes place within the cytoplasm.
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