Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MIC 430 > Lec 6: Transcription, Translation, & Genome Replication > Flashcards

Lec 6: Transcription, Translation, & Genome Replication Flashcards

1
Q

DNA viruses transcription can occur:

A

in nucleus or cytoplasm

only animal cells have nucleus so viruses can go there

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

RNA viruses transcription can occur:

A

in cytoplasm only

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Virus genomes: (7)

*note:

A

ss linear DNA
ds linear DNA
ss circular DNA
ds circular DNA

ss linear RNA
ds linear RNA
ss circular RNA

*note: NO ds circular RNA virus genome yet discovered

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

7 Baltimore classes of virus genomes:

A 
Class 1: ds DNA
Class 2: (+) DNA or (-) DNA
Class 3: ds RNA
Class 4: (+) RNA
Class 5: (-) RNA
Class 6: (+) RNA (rev-transc)
Class 7: ds DNA (rev-transc)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Reverse transcription =

A

mRNA –> DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Transcription of virus genomes classes: (7)

A

Class 1: ds DNA –> (+) mRNA

Class 2: (+) DNA –> ds DNA –> (+) mRNA
or (-) DNA –> ds DNA –> (+) mRNA

Class 3: ds RNA –> (+) mRNA

Class 4: (+) RNA –> (-) RNA –> (+) mRNA

Class 5: (-) RNA –> (+) mRNA

Class 6: (+) RNA (rev-transc) –> (-) DNA –> ds DNA –> (+) mRNA

Class 7: ds DNA (rev-transc) –> (+) mRNA
OR
ds DNA (rev-transc) –> (+) RNA –> (-) DNA –> dsDNA –> (+) mRNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

virus mRNA, is always designated

mRNA =

A

(+)

mRNA = (+) RNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q
  • A nucleic acid strand that has the same sequence as mRNA is labelled =
  • and a nucleic acid strand that has the sequence complementary to the mRNA is labelled =
A

(+)

-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

5’ AUGGCCUAA 3’ =

A

mRNA / “(+) RNA”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

3’ UACCGGAUU 5’ =

A

(-) RNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

The viruses with (+) RNA genomes =
& have…
However, only…

A

= (Classes 4 and 6)
…& have the same sequence as the virus mRNA.
…only the Class 4 genomes can function as mRNA.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

class 4 viruses aka “_____” must…

A

“retroviruses”

…must first reverse transcribe their ssRNA genomes to dsDNA before mRNA can be transcribed (+RNA > -DNA > dsDNA > mRNA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

(+) RNA and (+) DNA have the same sequence as

A

the mRNA (except that in DNA thymine replaces uracil).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

(−) RNA and (−) DNA have the

A

sequence complementary to the mRNA (except that in DNA thymine replaces uracil).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

ambisense genomes

A

Some ssDNA viruses and some ssRNA viruses have ambisense genomes. This means that that the polarity of the genome is part (+) and part (−).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

DNA or RNA can only be synthesized from

A

5’ to 3’ (starting from 3’ end on the template (-) strand)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

coding strand =

A

(+) DNA strand (leading)

5’-3’

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

template strand =

A

(-) DNA strand (lagging/okazaki)

3’-5’

19
Q

mRNA strand =

A

(+) mRNA strand
3’-5’
(same as template but with uracil)

20
Q

Anything opposite of mRNA =

Anything similar to mRNA =

A

(-) strand

(+) strand

21
Q

If template is (+): immediate product =

If template is (-): immediate product =

A

(-)

+

22
Q

a few single-stranded nucleic acids of viruses have a mixture of

A

(+) and (−) polarity within the strand, in other words there are open reading frames (ORFs) in both directions.

23
Q

+ RNA –>

A

proteins

24
Q
  • RNA –>
A

+ RNA –> proteins

25
Q

Ambisense viruses usually have

A

two hosts in which they can replicat

26
Q
  • In their vector or reservoir host, infection is usually =

- However, in another host, multiplication of the virus can be =

A
  • asymptomatic.

- lethal

27
Q

central dogma vs. mod.’d central dogma

A

mod.’d central dogma includes reverse transcription & RNA genome replication

28
Q

viruses must use

A

host cell translational machinery

29
Q

Virus molecules synthesized in the infected cell must also be transported to…

  • virus mRNAs are transported…
  • Virus proteins may be transported…
A

…particular sites.

  • …from nucleus to cytoplasm
  • …to various locations, including the nucleus
30
Q

transport vesicles –>

A

apical plasma membrane

31
Q

Golgi –>

A

basolateral plasma membrane

32
Q

Locations of virus genome replication in eukaryotic cells:

A

Cytoplasm:

  • some dsDNA
  • dsRNA
  • (+) RNA
  • (-) RNA (non-segmented genomes)
  • retroviruses & pararetroviruses (ssRNA –> dsDNA)

Nucleus:

  • some dsDNA
  • ssDNA
  • (-) RNA (segmented genomes)
  • retroviruses & pararetroviruses (dsDNA –> ssRNA)
33
Q

(Initiation of Genome replication)

Nucleic acid replication requires…

A

…priming = first reaction of a nucleotide with an –OH group on a molecule at the initiation site

34
Q

(Initiation of Genome replication)

Some ssDNA viruses, such as parvoviruses, use…

A

…self-priming. At the 3 end of the DNA there are regions with complementary sequences that can base pair.

35
Q

Synthesis of DNA needs RNA as a primer?

A
  • Okazaki fragments  primer = short mRNA fragments

- Viruses can also use  protein as a primer

36
Q

For some viruses the primer for initiation of nucleic acid replication is

A

the –OH group on a serine or tyrosine residue in a protein.

37
Q

Protein primers are not…

A

…removed once their role is performed and they are found linked to the 5’ ends of the genomes in virions.

38
Q

Enzymes used by viruses to replicate their genomes:

A

Virus Enzymes:

  • DNA dep DNA pol
  • RNA dep RNA pol
  • RNA dep DNA pol (rev-trans)

Cell Enzymes:

  • DNA dep DNA pol
  • DNA dep RNA pol (RNA pol II)
39
Q

Ori =

A

AT rich = easier to break bonds (only 2 H bonds in AT link)

40
Q

Semi conservative =

Conservative =

A

= 1 old + 1 new AND 1 old + 1 new

= 2 old AND 2 new

41
Q

ssRNA is replicated by

- both…

A

synthesis of complementary strands of RNA that are then used as templates for synthesis of new copies of the genome
- …both (+) and (−) strands of RNA accumulate in the infected cell not in equal amounts

42
Q

(+) RNA viruses accumulate…

A

an excess of (+) RNA over (−) RNA, and for minus strand RNA viruses the reverse is true.

43
Q
  • Some RNA viruses replicate their genomes..
  • Some DNA viruses replicate their genomes…
  • Both modes of genome replication involve…
A
  • …via a DNA intermediate.
  • …via an RNA intermediate.
  • …reverse transcription, which has two major steps:
    synthesis of (−) DNA from a (+) RNA template
    AND
    synthesis of a second DNA strand
44
Q

REPLICATION of virus genomes in the seven Baltimore Classes:

A

Class 1: dsDNA –> dsDNA

Class 2: (+) DNA –> dsDNA –> (+) DNA
or (-) DNA –> dsDNA –> (-) DNA

Class 3: dsRNA –> dsRNA
or dsRNA –> (+) RNA –> dsRNA

Class 4: (+) RNA –> (-) RNA –> (+) RNA

Class 5: (-) RNA–> (+) RNA –> (-) RNA

Class 6 (rev-transc): (+) RNA –> (-) DNA –> dsDNA –> (+) RNA

Class 7 (rev-transc): dsDNA –> (+) RNA –> (-) DNA –> dsDNA

MIC 430 (22 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions