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1. ECLIPSA

-Adsorbtie- Internalizare- Decapsidare

2. CRESTERE LOGARITMICA -Sinteza de proteine virale timpurii: (rol enzimatic si inedificarea incluziilor)

-sinteza de noi acizi nucleici virali-sinteza de noi proteine virale structurale

3. PLATOU-Maturarea proteinelor virale- Asamblarea acizilor nucleicicu proteinele structurale-Eliberarea virionilor progeni

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ADSORBTIA

Model in punte-v. anvelopate

Model creasta canion- v.neanvelopate

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Multiplii bacteriofagi atasati deperetele celular bacterian

HIV atasat de un limfocit T CD4

CORECEPTORI

http://upload.wikimedia.org/wikipedia/commons/5/52/Phage.jpg

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n erna zareprin fuziune-v. anvelopate-

factori de fuziuneprin endocitoza mediata de

receptori- v. Neanvelopate

Dupa Endocytosis, Edited by Ira Pastan and Mark C. Willingham, Plenum Press, N.Y., 1986

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VIRUSURI ADN1. SINTEZA PROTEINELOR TIMPURII

INCLUZII

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2.REPLICAREA VIRUSURILOR ADNIntranuclear (cu exceptia poxviridae)Fidelitate mare a transcrierii

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VenkatramanRamakrishnan Thomas A. Steitz Ada E. Yonath

1/3 of the prize 1/3 of the prize 1/3 of the prize

United Kingdom USA IsraelMRC Laboratory of Molecular BiologyCambridge, UK

Yale UniversityNew Haven, CT, USA; HowardHughes Medical Institute

Weizmann Institute of ScienceRehovot, Israel

b. 1952b. 1940 b. 1939

PREMIUL NOBEL PENTRU CHIMIE 2009 "for studies of thestructure and function of the ribosome"

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VIRUSURI ARNSS CU POLARITATE POZITIVAintracitoplasmatic

Genom parental=ARNm-debut cu traducereproteine

ARNm viral nu arestructura 5' cap metilatatipica pentru ARNmeucariot , ci o pista deaterizare pentru ribozomi

Gazda eucariota utilizeazapentru sinteza proteinelorARNm monocistronic

ARNm viral actioneaza caun transcriptmonocistronic

Picornaviridae, flaviviridae

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VIRUSURI ARNss CU POLARITATE NEGATIVAobligatoriu asociate cu transcriptaza virala

intracitoplasmatic, cu exceptia Orthomixoviridae

Prima etapa =sinteza , prinintermediul transcriptazei virale, aspirei complementare ARNss cupolaritate pozitiva=ARNm

Virusul sintetizeaza mai multespecii de ARNm monocistronic sautranscriptele primare suntprelucrate prin splicing de gazdapentru a rezulta mai multe speciide ARNm monocistronic

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CLASIFICAREA BALTIMORE

I: virusuri A DN ds (Adenoviruses , Herpesviruses , Poxviruses )II : virusuri A DN ss (Parvoviruses )III: : virusuri ARN ds ( Reoviruses )IV: : virusuri ARNss (+) ( Picornaviruses )V: : virusuri ARN SS () (Orthomyxoviruses , Rhabdoviruses )VI: : virusuri ARN ss RT (Retroviruses )VII: : virusuri ADN ds-RT ( Hepadnaviruses )

http://en.wikipedia.org/wiki/DsDNA_virushttp://en.wikipedia.org/wiki/DsDNA_virushttp://en.wikipedia.org/wiki/Adenovirushttp://en.wikipedia.org/wiki/Herpesvirushttp://en.wikipedia.org/wiki/Poxvirushttp://en.wikipedia.org/wiki/DsDNA_virushttp://en.wikipedia.org/wiki/SsDNA_virushttp://en.wikipedia.org/wiki/Parvovirushttp://en.wikipedia.org/wiki/DsRNA_virushttp://en.wikipedia.org/wiki/Reovirushttp://en.wikipedia.org/wiki/Positive-sense_ssRNA_virushttp://en.wikipedia.org/wiki/Picornavirushttp://en.wikipedia.org/wiki/Negative-sense_ssRNA_virushttp://en.wikipedia.org/wiki/Orthomyxovirushttp://en.wikipedia.org/wiki/Rhabdovirushttp://en.wikipedia.org/wiki/Retrovirushttp://en.wikipedia.org/wiki/DsDNA-RT_virushttp://en.wikipedia.org/wiki/Hepadnavirushttp://en.wikipedia.org/wiki/Hepadnavirushttp://en.wikipedia.org/wiki/DsDNA-RT_virushttp://en.wikipedia.org/wiki/DsDNA-RT_virushttp://en.wikipedia.org/wiki/DsDNA-RT_virushttp://en.wikipedia.org/wiki/Retrovirushttp://en.wikipedia.org/wiki/Rhabdovirushttp://en.wikipedia.org/wiki/Orthomyxovirushttp://en.wikipedia.org/wiki/Negative-sense_ssRNA_virushttp://en.wikipedia.org/wiki/Picornavirushttp://en.wikipedia.org/wiki/Positive-sense_ssRNA_virushttp://en.wikipedia.org/wiki/Reovirushttp://en.wikipedia.org/wiki/DsRNA_virushttp://en.wikipedia.org/wiki/DsRNA_virushttp://en.wikipedia.org/wiki/DsRNA_virushttp://en.wikipedia.org/wiki/Parvovirushttp://en.wikipedia.org/wiki/SsDNA_virushttp://en.wikipedia.org/wiki/SsDNA_virushttp://en.wikipedia.org/wiki/DsDNA_virushttp://en.wikipedia.org/wiki/Poxvirushttp://en.wikipedia.org/wiki/Herpesvirushttp://en.wikipedia.org/wiki/Adenovirushttp://en.wikipedia.org/wiki/DsDNA_virushttp://en.wikipedia.org/wiki/DsDNA_virushttp://en.wikipedia.org/wiki/DsDNA_virus

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MATURARE-ASAMBLARE-ELIBERAREIn maturare si asamblare intervin chaperoni-dirijeaza asamblarea post-translationala,

impachetarea proteinelor si previn agregarea instructuri nefunctionale a lanturilor proteice nousintetizate.-sunt implicati in transportul transmembranar

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SUMAR Replicarea virusurilor se desfsoar n trei faze succesive. ECLIPSA ( adsorbtie, internalizare si decapsidare)

Adsorbtia este urmarea cuplrii unor proteine virale superficiale (liganzi sau antireceptori) dereceptori situati pe membrana celular. Acestia sunt de nalt afinitate (ce induc si modificariconformationale in virionii adsorbiti) si uneori si de joas afinitate (co-receptori)

Internalizarea se realizeaz fie prin viropexie (endocitoz), fie prin fuziunea anvelopei virale cumembrana celular

Decapsidarea este un proces simultan cu internalizarea n care intervin determinant proteazecelulare. Absenta acestor proteaze fac celula nesusceptibil sau partial permisiv la infectia viral

FAZA DE CRESTERE LOGARITMIC ( sinteza proteinelor timpurii , sintezagenomurilor progene , sinteza proteinelor tardive (structurale)

fidelitatea replicrii este mai mare la virusurile ADN comparativ cu virusurile ARN. In plus,virusurile mai complexe sunt mai stabile fizic dect virionii mici.

FAZA DE PLATOU (maturare, asamblare si eliberarea virionilor progeni din celulainfectat)

Asamblarea este guvernat de legile simetriei care tind s asigure soliditatea particulei virale caelement cu minim energie liber. Uneori, n procesul de asamblare intervin proteinelechaperon (petitor) care dirijeaz capsomerele virale spre areale ale membranei celulare unde seasambleaz virionii progeni. Acestia din urm se elibereaz prin nmugurire (n cazul virusuriloranvelopate) sau prin citoliz (n cazul virusurilor neanvelopate).

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http://www.virology.net/Big_Virology/BVFamilyGroup.html

http://www.virology.net/Tutorials.html .-puteti nvtareplicare viral,- nu trebuie dect s v decideti dac vreti sfiti pentru cteva minute un poliovirus, un coronavirus sauchiar HIV! Dac nu stiti ceva sunteti rapid trimisi la studiu,ctre foarte multe situri specializate

Aceleasi informaii, n versiuni mai sofisticate se obtin de la : http://www2.tulane.edu si www.virology.science.org/jov . (Jov este sintagma pentru

Journal of Virology)

http://www.virology.net/Big_Virology/BVFamilyGroup.htmlhttp://www.virology.net/Big_Virology/BVFamilyGroup.htmlhttp://www.virology.net/Tutorials.htmlhttp://www.virology.science.org/jovhttp://www.virology.science.org/jovhttp://www.virology.net/Tutorials.htmlhttp://www.virology.net/Big_Virology/BVFamilyGroup.htmlhttp://www.virology.net/Big_Virology/BVFamilyGroup.html