Virus de ARN: Diferenzas entre revisións

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Relacionados paro diferentes dos virus de ARN son os [[viroide]]s e [[satélite (viroloxía)|virus satélites de ARN]], que se clasifican en grupos á parte.
 
===VirusFiloxenia dos virus de ARN de cadea positiva===
 
Este é o grupo máis grande de virus de ARN con 30 familias. Fixéronse diversos intentos para agrupar estas [[familia (bioloxía)|familias]] en [[orde (bioloxía)|ordes]]. As propostas presentadas estaban baseadas na análise das [[ARN polimerase]]s e están aínda sendo consideradas. Ata agora as suxerencias propostas non tiveron ampla aceptación debido ás dúbidas sobre a conveniencia de que un só xene determine a [[taxonomía]] dun [[clado]].
This is the single largest group of RNA viruses with 30 families. Attempts have been made to group these families in higher orders. These proposals were based on an analysis of the RNA polymerases and are still under consideration. To date the suggestions proposed have not been broadly accepted because of doubts over the suitability of a single gene to determine the taxonomy of the clade.
 
TheAs proposedclasificacións classificationpropostas ofpara positiveos strandvirus RNAde virusesARN isde basedcadea onpositiva thebaseadas RNAno dependentestudo RNAdo polymerase.xene Threeda groupsARN havepolimerase beenARN-dependente recognisedestablecen tres grupos:<ref name=Koonin>{{cite journal | author = Koonin EV | year = 1991 | title = The phylogeny of RNA-dependent RNA polymerases of positive-strand RNA viruses | url = | journal = J Gen Virol | volume = 72 | issue = 9| pages = 2197–206 }}</ref>
 
I. O grupo de tipo picorna ou Picornavirata, formado por: bymovirus, comovirus, nepovirus, nodavirus, picornavirus, potyvirus, sobemovirus e un subconxunto de luteovirus (virus do amarelado da remolacha occidental e virus do enrolamento da folla da pataca).
I. Bymoviruses, comoviruses, nepoviruses, nodaviruses, picornaviruses, potyviruses, sobemoviruses and a subset of luteoviruses (beet western yellows virus and potato leafroll virus) - the picorna like group (Picornavirata).
 
II. O grupo de tipo flavi ou Flavivirata, que comprende: carmovirus, dianthovirus, flavivirus, pestivirus, tombusvirus, [[bacteriófago]]s de ARN monocatenarios, virus da hepatite C e un subconxunto de luteovirus (virus do anannismo amarelo da cebada).
II. Carmoviruses, dianthoviruses, flaviviruses, pestiviruses, tombusviruses, single-stranded RNA bacteriophages, hepatitis C virus and a subset of luteoviruses (barley yellow dwarf virus) - the flavi like group (Flavivirata).
 
III. O grupo de tipo alfa ou Rubivirata, que inclúe a: alphavirus, carlavirus, furovirus, hordeivirus, potexvirus, rubivirus, tobravirus, tricornavirus, tymovirus, virus da mancha foliar clorótica da mazá, virus do amarelado da remolacha e virus da hapatite E.
III. Alphaviruses, carlaviruses, furoviruses, hordeiviruses, potexviruses, rubiviruses, tobraviruses, tricornaviruses, tymoviruses, apple chlorotic leaf spot virus, beet yellows virus and hepatitis E virus - the alpha like group (Rubivirata).
 
APropúxose divisionunha ofdivisión thedo alphasupergrupo likede tipo alfa (os de tipo Sindbis-like) supergroupbaseándose onno theestudo basisdun ofnovo adominio novellocalizado domainpreto locateddo near theextremo [[N-terminal]] terminide ofproteínas theimplicadas proteinsna involved inreplicación viral replication has been proposed.<ref name=Rozanov1992>Rozanov MN, Koonin EV, Gorbalenya AE (1992) Conservation of the putative methyltransferase domain: a hallmark of the 'Sindbis-like' supergroup of positive-strand RNA viruses. J Gen Virol 73 (8):2129-2134</ref> TheOs twodous groupsgrupos proposedpropostos areson: theo 'grupo dos "altovirus' group" (alphavirusesalphavirus, furovirusesfurovirus, hepatitisvirus Eda virushepatite E, hordeiviruseshordeivirus, tobamovirusestobamovirus, tobravirusestobravirus, tricornavirusestricornavirus ande probablyprobablemente rubivirusesrubivirus); ande theo 'typovirus'grupo groupdos "tipovirus" (applevirus chloroticda leafmancha spotfoliar virusclorótica da mazá, carlavirusescarlavirus, potexvirusespotexvirus ande tymovirusestymovirus).
 
TheO alphasupergrupo likealfa supergrouppode canser beademais furtherdividido divideden intotres three [[clades]]clados: theo de tipo rubi-like, de tipo tobamo-like ande tymo-likede virusestipo tymo.<ref name=Koonin1993>Koonin, EV, Dolja VV (1993) Evolution and taxonomy of positive-strand RNA viruses: implications of comparative analysis of amino acid sequences. Crit Rev Biochem Mol Biol 28:375-430</ref>
 
AdditionalTraballos workadicionais hasidentificaron identifiedcinco fivegrupos groupsde ofvirus positivede strandedARN RNAde virusesfibra containingpositiva fourque conteñen, threerespectivamente, threecatro, threetres, andtres, onethres ordere unha orde(s) respectively.<ref name=Ward1993>{{cite journal | author = Ward CW | year = 1993 | title = Progress towards a higher taxonomy of viruses | url = | journal = Res Virol | volume = 144 | issue = 6| pages = 419–453 }}</ref> TheseEstas fourteencatorce ordersordes containconteñen 31 virusfamilias familiesde virus (includingincluíndo 17 familiesfamilias ofde plantvirus virusesde plantas) ande 48 generaxéneros (includingincluíndo 30 generaxéneros ofde plantvirus virusesde plantas). ThisEsta analysisanálise suggestssuxire thatque os alphavirusesalphavirus ande flavivirusesflavivirus canpoden besepararse separateden intodúas two familiesfamilias, - theos Togaviridae ande os Flaviridae, respectivelypero -suxire butque suggestsoutras thatasignacións othertaxonómicas taxonomicpoden assignmentsser incorrectas, suchcomo as thedos pestivirusespestivirus, hepatitisvirus da hepatite C virus, rubivirusesrubivirus, hepatitis E virus andda arteriviruses,hepatite mayE bee incorrectarterivirus. TheOs coronavirusescoronavirus ande torovirusestorovirus appearparecen toser befamilias distinctdistintas familiesde indistintas distinctordes orderse andnon notdistintos distinctxéneros generada ofmesma thefamilia samecomo familyson as currentlyclasificados classifiedactualmente. TheOs luteovirusesluteovirus appearparecen toser bedúas twofamilias familiese rathernon thanunha onee ando applevirus chloroticda leafmancha spotfoliar virusclorótica appearsda notmazá toparece beque anon é un closterovirus butsenón aun newnovo genus ofxénero thede Potexviridae.
 
; Evolución
; Evolution
 
TheA evolutionevolución ofdos thepicornavirus picornavirusesbaseada basedna onanálise an analysis ofdas theirsúas RNAARN polymerasespolimerases ande [[helicase]]s appearsparece todatar datea todiverxencia the divergence of thedos [[eukaryoteeucariota]]s.<ref name=Koonin2008>Koonin EV, Wolf YI, Nagasaki K, Dolja VV (2008) The Big Bang of picorna-like virus evolution antedates the radiation of eukaryotic supergroups. Nat Rev Microbiol 6(12):925-939</ref> TheirOs putativeseus ancestorssupostos includeantepasados thepoderían bacterialser group IIos [[retroelementretroelemento]]s de grupo II bacterianos, thea familyfamilia of HtrAde [[protease]]s andHtrA DNAe [[bacteriophage]]sos bacteriófagos de ADN.
 
===Virus de ARN bicatenario (dsRNA)===