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Viry studované v Laboratoři strukturní virologie : pikornaviry včelí viry Leishmania RNA virus

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Proč viry způsobují onemocnění ?. Co jsou viry - jsou živé ?. Metody studia struktury virů : rentgenová krystalografie kryo-elektronová mikroskopie. Viry studované v Laboratoři strukturní virologie : pikornaviry včelí viry Leishmania RNA virus bakteriofág 812K1. Infekce chřipkou. - PowerPoint PPT Presentation

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Viry studovan v Laboratoi strukturn virologie: pikornaviry vel viry Leishmania RNA virus bakteriofg 812K1Co jsou viry - jsou iv?Metody studia struktury vir: rentgenov krystalografie kryo-elektronov mikroskopiePro viry zpsobuj onemocnn?Albert Bosch highlights that according to data provided by the World Health Organization, viral diseases represent two thirds of the total number of medical appointments due to infections.

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Infekce chipkouVirion infekn virov partikuleDv formy existence viru:

Infekce bukyCarrier of genetic information from cell to cell:- "extracellular organelle- packages viral genome- escapes from infected cell- survives transfer from one cell to another- attaches, penetrates, initiates replication in new host cell

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Viruses as pathogens - viruses bear the genetic information needed to harness cellular biosynthetic machinery and replicate itself - hence, selective advantage for virus may be selective disadvantage for host - some of the most deadly pathogens: polio, HIV, Ebola, SARS, influenza, smallpox - evolution of host defense (immunity)

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Jsou viry iv?Znaky shodn s obvyklou definic ivotaZnaky odlin od obvykl definice ivotaMaj genyNemaj bunnou strukturuVyvjej se (evoluce)Nemaj metabolismusPodlhaj pirozen selekciPro rozmnoen potebuj hostitelskou bukuRozmnouj seNov viry vznikaj sloenm z stThese features show that viruses are simple macromolecular machines and thus we can aspire to understand them at the atomistic level.

Cyklus bunnho dlendsDNAdsDNAssRNAProteinyBunn organismyVirydsDNAssRNAProteinyReplikaceTranskripceTranslaceDNARNAProteiny

Struktury virion

HeliklnIkosahedrlnKomplexnNepravidelnWILHELM CONRAD RNTGEN (1845-1923)1901 Nobel Laureate in Physicsdiscovery of the remarkable rays subsequently named after him

MAX VON LAUE (1879-1960)1914 Nobel Laureate in Physicsfor his discovery of the diffraction of X-rays by crystals

Wavelength and diffraction

Wavelength comparison of X-rays and visible light

38l

70m

James Batcheller Sumner(1879-1960)1946 Nobel Laureate in Chemistryfor his discovery that enzymes can be crystallized

FRANCIS HARRY COMPTON CRICK (1916~2004)JAMES DEWEY WATSON (1928~)MAURICE HUGH FREDERICK WILKINS (1916~2004)1962 Nobel Laureates in Physiology and Medicine for their discoveries concerning the molecular structure of nuclear acids and its significance for information transfer in living material.

Rosalind FranklinMaurice Wilkins James Watson and Francis Crick

Max Ferdinand Perutz (1914 2002)John Cowdery Kendrew (1917 1997)1962 Nobel Laureate in Physicsfor their studies of the structures of globular proteins

Information from X-ray diffraction experiment

[0;0;0]xyz

1. Virus purification2. Crystallization3. Diffraction data

4. Solve structure

1. Virus purification3. cryo-EM4. Reconstruction

2. Grid preparation

Rhinoviry 40% nachlazen finann nklady $16bn/rok v USAMcMinn et al. Clin Infect Dis 2001. Image by Heng Soy, KI Media 2012.Enteroviry (EV71) nemoc rukou, nohou a st encefalitida

PicornaviryI would like to start my presentation by defining biological significance of my project.My research is focused on structural studies of picornaviruses that include some of the most common human pathogens. For example, rhinoviruses are responsible for about 40$ of common cold cases. The economic damage caused by rhinoviruses was estimated to be 16bn dollars per year in the united states alone. Similar expenses are expected for European union.Enterovirus 71 induces yearly outbreaks of hand-foot-and-mouth disease mostly in south-east Asia. About 5% of the infected children develop encephalitis that can be fatal or result in permanent brain damage. This magnetic resonance image shows inflammation in left section of cerebellum caused by EV71 infection. The three years old patient lost ability to speak.Currently no antiviral drugs are available against rhinoviruses or enteroviruses. More basic research is needed to improve our understanding of picornavirus biology to allow identification of new targets for antiviral drugs. My research will address these requirements by -> next slide25ivotn cyklus pikornavir

Virus replication factory aspiring to answer basic biological questions about picornavirus life cycle. It is well established that picornaviruses enter cells by receptor mediated endocytosis. However, it is not known how is the picornavirus ssRNA genome delivered from virions across the membrane of the endosome into cell cytoplasm. That is our first research question.When in the cytoplasm the genome is translated into a polyprotein that is then cleaved into functional subunits. The viral proteins induce formation of so called virus-replication factories that contain lipid vesicles derived from intra-cellular membranes, viral and cellular proteins, ribosomes and viral RNAs. We will use modern cryo-electron tomography approaches to characterize the factories on molecular level.In addition we will structurally characterize picornavirus genome replication and recombination processes that happen in the vicinity of the replication factories.Finally, we will determine picornavirus virion assembly mechanism.26Vel viry

aspiring to answer basic biological questions about picornavirus life cycle. It is well established that picornaviruses enter cells by receptor mediated endocytosis. However, it is not known how is the picornavirus ssRNA genome delivered from virions across the membrane of the endosome into cell cytoplasm. That is our first research question.When in the cytoplasm the genome is translated into a polyprotein that is then cleaved into functional subunits. The viral proteins induce formation of so called virus-replication factories that contain lipid vesicles derived from intra-cellular membranes, viral and cellular proteins, ribosomes and viral RNAs. We will use modern cryo-electron tomography approaches to characterize the factories on molecular level.In addition we will structurally characterize picornavirus genome replication and recombination processes that happen in the vicinity of the replication factories.Finally, we will determine picornavirus virion assembly mechanism.27

cutaneous leishmaniasismetastasis to nasopharyngeal tissuesIves et al. Science, 2011Olivier. Nature, 2011Free Dictionary

Leishmania RNA virus 1

Totiviry - Leishmania RNA virus 1 (LRV1)

Fujimura et al. PNAS, 2011Naitow et al. NSMB 200229Totivirus RNA lack M7G Cap, its translation is possible because capsid proteins have de-capping activity and thus generate decoy for cellular RNA-degradation machinery. Mutations in the de-capping active site greatly reduce virus protein production no dsRNA is generated (this happens only in particles). Furthermore de-capping activity of LA virus can be inhibited with 7-methyl-GDP.

cryo-EM tomography of Leishmania promastigotes in lysosome conditions to study release of the LA-virus from cells (Leishmania cells are 500nm tick, LA is 40nm in diameter)

cryo-EM tomography of Leishmania promastigotes in lysosomeKryo-EM fga 812 infikujcho S. aureus

Daniel Nmeek, Ji Novek, Lubomr Kovik

Infekce fgem T4

Co jsou viry - jsou iv?Metody studia struktury vir: rentgenov krystalografie kryo-elektronov mikroskopiePro viry zpsobuj onemocnn?Albert Bosch highlights that according to data provided by the World Health Organization, viral diseases represent two thirds of the total number of medical appointments due to infections.

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Picornavirus virion