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Flashcards in DNA multiplication Deck (22)
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1
Q

Eclipse

A

The central step of virus multiplication

  • From first mRNA → First virion assembly
2
Q

Give the steps of the eclipse

A
  1. Early transcription, translation: Enzymes
  2. Replication: NA multiplication
  3. Late transcription, translation: Structural proteins
3
Q

Multiplication of viral NA is dependent on…

A

The host cell

4
Q

The Baltimore system

A

Classification of viral families according to their NA/multiplication strategy

5
Q

Give the classifications of the Baltimore system

A
  1. dsDNA
  2. ssDNA
  3. dsRNA
  4. +ssRNA
  5. -ssRNA
  6. Viruses using reverse transcriptase
6
Q

Properties of virus multiplication: DNA virus

A

Nucleic acid similar to cellular genetic material

7
Q

Properties of virus multiplication: RNA virus

A

In the cell, RNA doesn’t store information

  • Enzyme needed for replication
    • RNA dependent RNA polymerase (RdRp)
  • Mutations during replication - Quick evolution
8
Q

Properties of virus multiplication:Coding system

A
  • Monocistronic cell → Separate mRNAs for the proteins
  • Virus: Lack of space: Can be polycistronic
9
Q

Steps of transcription, translation + NA replication: Double-stranded DNA viruses (dsDNA)

A
  1. Early transcription
  2. Early translation
  3. Replication
  4. Late transcription, translation
10
Q

Double-stranded DNA viruses (dsDNA): Early transcription

A
  • Viral DNA enters nucleus
  • Cellular transcriptase → mRNA
11
Q

Which dsDNA viruses don’t use cellular transcriptase?

A
  • Poxvirus
  • Asfarviridae family

They use their own viral transcriptase

Multiplication in the cytoplasm

12
Q

Double-stranded DNA viruses (dsDNA): Early translation

A
  • On the surface of ribosomes → Cellular translation
  • Non-structural protein synthesis
13
Q

Double-stranded DNA viruses (dsDNA): Replication

A
  • Viral replicase
    • Better than cellular
    • High productivity
14
Q

Double-stranded DNA viruses (dsDNA): Late transcription, translation

A
  • Progeny DNA serves as a template
  • High structural protein synthesis
15
Q

Steps of transcription, translation + NA replication: Single-stranded DNA viruses (ssDNA)

A
  1. Transcription
  2. Translation
  3. Replication
16
Q

Single-stranded DNA viruses form…

A

Self-priming hairpins

  • Cellular polymerase synthesises complimentary thread
17
Q

Single-stranded DNA viruses (ssDNA): Transcription

A

mRNA synthesis from the coding thread

18
Q

Single-stranded DNA viruses (ssDNA): Translation

A

Cellular translation

  • Polycistronic mRNA: Enzymatic cleavage
19
Q

Single-stranded DNA viruses (ssDNA): Replication

A
  • Small genome: No own polymerase
  • Cellular polymerase copies dsDNA
  • Own thread is eventually removed
20
Q

Single-stranded DNA virus (ssDNA) examples

A
  • Parvovirus
  • Circoviridae family
21
Q

Multiplication of viruses with a circular genome

e.g Parvovirus

A
  • Multiplication only in S-phase (dividing) cells
    • In enterocytes, embryo, bone marrow cells
22
Q

Dependovirus multiplication

A
  • Uses the replicase of adeno- or herpesviruses