Virus Structure/ Function Flashcards Preview

Disease and Defense Unit 3 > Virus Structure/ Function > Flashcards

Flashcards in Virus Structure/ Function Deck (7)
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1
Q
  • Virus definition? Needs what of host? Break Koch postulate how? Genetic material directs what?
  • Survival strategy? (3)
  • Class schemes: System named based on physical properties? 4 characteristics? (4)
  • Seven classes of viral genomes? (7)
  • What is created in host? (2)
  • RNA viruses need to bring or translate what?
  • RDRP then generates what? (2)
  • mRNA then what?
  • (+) strand vs. (-) strand?
    • strand still has to convert to dsDNA why?
  • What strand has many deadly viruses?
A
  • Submicroscopic (filterable, infectious, obligate intracellular parasite; machinery; can’t grow in vitro; production of new particles
  • House their genetic material in capsids, genome contains info to initiate and complete infectious cycle; establish a relationship with host
  • Classical; nature DNA/RNA, symmetry of capsid, naked or envelope, dimensions of virion
  • dsDNA, gapped circular DNA with reverse trans., ssDNA, dsRNA, (+) RNA, (-) RNA, (+) RNA with DNA intermediate
  • Proteins and genetic material
  • RdRP
  • RNA genome and mRNA for next virus
    • can be translated directly
  • Replicate genetic info
  • (-) RNA
2
Q
  • Baltimore class system based on? Grouped how?
  • Studying viruses: Egg system? Microscope type? 3 cell culture systems? (2) Plaque assay has serial dilutions that what? Immune response with?
  • Capsids: Made of? Shapes? (2) Genome wrapped how?
  • Enevelope: Lipid with? Helps with? (3)
  • Growth chart: 1.) Eclipse phase: Hours? Replication? 2.) Latency: Hours? Rep? Then?
A
  • Central dogma; seven groups and how they turn genetic material to mRNA
  • Place in eggs; electron microscope; primary (directly from tissue) short lifespan; cell from tumors which may have infinite lifespan; then plated; Western or ELISA
  • protein; helical or icosohedral; inside or out
  • glycoprotiens; entry, assembly, evasion
    1. ) 0-12 hours; no 2.) 0-16 hours; yes 3.) Release virus
3
Q
  • Attachment: Suseptible host? Resistant? Permissive? Need what to replicate? Receptors per virus?
  • Types of entry? (2)
  • Gene expression: All viruses encode? 5 ways they maximize space?
  • Replication: Steps? (3)
  • Assembly: Helical: genomic RNA coated when? Icosohedral coated when? (2)
  • Eggress: NAked capsids? Enveloped?
A
  • Has a receptor (may or may not replicate); no receptor; capacity to replicate (may not have receptor); Sus and permiss; usually >1
  • Fusion or endocytosis
  • RDRP; splicing, ambiescence (code both ways), RNA editing, poly proteins, suppressed stop codons
  • decode genome to make mRNA and protein, make copies of genome, assemble the two
  • Synthesis; around genome of fed in
  • Cells lyse; go through membranes (could be ER or golgi)
4
Q

Viral pathogenesis:

  • Tropism? Many start with? Ex?
  • Virulance?
  • Pathogenicity?
  • Iceberg concept?
  • Common initial sites? (4)
  • Incubation period? Varies? Ex?
  • Factors that influence virulence: genes that effect? (4)
  • Host factors? (6)
  • Virus induced immunopathology? Dengue virus example? Another example?
  • Typical 3 steps of acute, primary virus?
A
  • Cells or tissue of a host that support a particular virus; epithelium; HIV with CD4 cells
  • Degree to which virus can cause disease
  • Ability to cause disease
  • Only a few viruses under right conditions lyse and kill host
  • skin, mucus membranes, GI tract, urinary tract
  • Time b/n when virus gets in and start of infection; yes; flu = short; Hep = long
  • ability to replicate, modify host defense, facilitate spread, directly toxic to host
  • Receptors, cell type, age, genetics, exposure hostory, immune status
  • Immune response causes virulance; increases risk of future infections, complex formation
  • Uninfected –> Infected –> Approp immune reposponse or not
5
Q
  • 4 viruses related to cancer?
  • 3 outcomes with virus?
  • Acute local vs acute systemic: First viral spot? Viremia (spread to other spots)? Incubation time?Immunity? Ab?
  • Persistant vs. Latent: Ex?
  • Example of acute local? (2) Acute systemic? (2) Chronic? Latent? Slow? (2)
  • More serotypes means?
  • What type of deficiency is more dangerous with viruses?
A
  • EBV, HIV, Hep C, Papilloma
  • Acute infection, persistant, latent
  • Acute local: Epi; no; short; short; IgA
  • Acute systemic: Epi; primary and secondary by entering blood; Longer; Life long; IgG/IgA
  • Persistant = ongoing virus production = Hep B
  • Latent = Has true dormant periods = HSV, EBV HPV
  • Less AB’s to recognize it and greater virulence
  • T cell
6
Q
  • What is cytopathic effects? Direct? Indirect?
  • Synctia?
  • Growth?
  • Apoptosis?
  • Other effects of viruses? (3)
  • Typical host response? (3) Ex: APOBEC3G does what? But what?
  • IFN response: Released by? Helps who? Type 1? Released by who? Type 2? Released by who? Made in response to? Antiviral state due to? Altering TF’s blocks what? Often triggered by? (2)
  • Innate responses: OASa degrades? PKR decreases what? Increase what presentation?
A
  • Not in interest of virus to kill host but damage is ok; lyse cells; integrate, cause inflamm
  • Virus mediated fusion to cells
  • Turn cells into replication machines
  • Inhibit it
  • Nuclear alteration, break chrom., add inc. bodies
  • Release INF, apoptose, restrction factors; integrates with HIV genome to kill it; HIV mutates
  • Infected cell; adjacent cells; alpha and beta; infected cells; gamma; NK cells and T cells; finding antigen; Type 1 mostly; Cell prolif; dsRNA or abnormal nucleic acids; MRNA, translation, MHC to T cells
7
Q
  • Innate response: Specific? TLRs identify what? (2) TLR7? TLR9? Recognize factors such as APOBEC? INFa from? INFB from? JAK/STAT signalling? PKR/Oasa? INF prepares what?
  • Adaptive response: Humoral: Group specific? Type specific?
  • Cell mediated primarily? Problem with hepatocytes? Th1 release? (3) Type response? Th2 release? (3) Type response?
  • Innate job? Adaptive job?
  • Virus evasion tactics? (5)
A
  • No; viral nucleic acid, dsRNA; viral RNA; unmethylated CpG; yes; leukocytes; epithelia; yes; play big role; Capsase system for dsRNA
  • bind common viral epitope; bind epitope of virus subtype
  • CD8; not APC’s; INFgamma, IL2, IL12 proinflammatory; IL4, IL5, IL10 –> Ab response
  • Containment; Destroy
  • Drift/shift; Inhibit INF; Mimicry, Downreg. MHC, Infect immune system