Podcast
Questions and Answers
Polymerase begins at 3’ end because that’s where the template is being read and stops at the end of a transcription-regulating sequence (TRS) 2. Polymerase then pauses and disassociates the nascent RNA chain from TRS> jumps to TRS located at the end of the leader sequence (______) - Dissociated nascent RNA chain forms RNA-RNA hybrids of complementary sequences at 5’ TRS
Polymerase begins at 3’ end because that’s where the template is being read and stops at the end of a transcription-regulating sequence (TRS) 2. Polymerase then pauses and disassociates the nascent RNA chain from TRS> jumps to TRS located at the end of the leader sequence (______) - Dissociated nascent RNA chain forms RNA-RNA hybrids of complementary sequences at 5’ TRS
template switching
RNA pol can pause and dissociate at any of the TRSs
RNA pol can pause and dissociate at any of the TRSs
transcription-regulating sequences
Each of the subgenomic ‘-‘ strands are used to make a ‘+’ strand mRNA, then transcript it into proteins - This discontious model explain recombination between viral genoms: 1. Viral RNa polymerase can switch between two different positive-strand genome RNAs if they are both in the same cell 2. Could be two different virus strains infecting the same cell, or mutations in the virus genome during replication 3. Template switching may help with genome repair and/or generate new viral strains/variants >>After dissociation, polymerase has to find another template or transcription will abort> can lead to template switch Section 1.7 - Assembly of virions takes place at intracellular membrane structures- ERGIC (endoplasmic reticulum Golgi intermediate compartment); involves in transport, processing and modification of proteins. Generally located in the perinuclear (around or near the nucleus) region of the cell
Each of the subgenomic ‘-‘ strands are used to make a ‘+’ strand mRNA, then transcript it into proteins - This discontious model explain recombination between viral genoms: 1. Viral RNa polymerase can switch between two different positive-strand genome RNAs if they are both in the same cell 2. Could be two different virus strains infecting the same cell, or mutations in the virus genome during replication 3. Template switching may help with genome repair and/or generate new viral strains/variants >>After dissociation, polymerase has to find another template or transcription will abort> can lead to template switch Section 1.7 - Assembly of virions takes place at intracellular membrane structures- ERGIC (endoplasmic reticulum Golgi intermediate compartment); involves in transport, processing and modification of proteins. Generally located in the perinuclear (around or near the nucleus) region of the cell
viral genomes
Helical nucleocapsids (curved blue lines) containing genome RNA are delievered from site of synthesis to these membranes ______
Helical nucleocapsids (curved blue lines) containing genome RNA are delievered from site of synthesis to these membranes ______
Virus particles are formed by budding into the lumen of these ______ (virions acquire donut-shaped cores)
Virus particles are formed by budding into the lumen of these ______ (virions acquire donut-shaped cores)
Progress to smaller and more uniformly dense cores as transit through ______ membrane, envelope proteins also undergo glycosylation
Progress to smaller and more uniformly dense cores as transit through ______ membrane, envelope proteins also undergo glycosylation
M and E proteins play important roles in the formation of the virus envelops by budding
M and E proteins play important roles in the formation of the virus envelops by budding
Enveloped virus-like particles can be formed in ______ when only M and E are expressed> which indicates that M and E proteins are sufficient in forming the particles
Enveloped virus-like particles can be formed in ______ when only M and E are expressed> which indicates that M and E proteins are sufficient in forming the particles
C-terminal cytoplasmic tail of M is though to interact with packaging signals in N> ensures only full-length viral RNA gets packaged into virons - HE (if present) and S are incorporated into the membrane through interactions with the M protein - As all these proteins transverse through Golgi, envelope proteins are glycosylated, mature ______ are packaged into vesicles> targete.
C-terminal cytoplasmic tail of M is though to interact with packaging signals in N> ensures only full-length viral RNA gets packaged into virons - HE (if present) and S are incorporated into the membrane through interactions with the M protein - As all these proteins transverse through Golgi, envelope proteins are glycosylated, mature ______ are packaged into vesicles> targete.
Which type of fusion protein tends to form trimers and has two distinct conformations?
Which type of fusion protein tends to form trimers and has two distinct conformations?
What is the primary location for the synthesis, folding, and assembly of fusion proteins?
What is the primary location for the synthesis, folding, and assembly of fusion proteins?
Which statement accurately describes the energy requirement for viral membrane fusion mediated by fusogens?
Which statement accurately describes the energy requirement for viral membrane fusion mediated by fusogens?
Which type of fusion protein involves rearrangement of multimers of protein subunits but only minor conformational changes at the tertiary level?
Which type of fusion protein involves rearrangement of multimers of protein subunits but only minor conformational changes at the tertiary level?
Which cellular structure do many DNA viruses use for replication and can establish latency?
Which cellular structure do many DNA viruses use for replication and can establish latency?
What is a target for antiviral drugs in the virus replication cycle?
What is a target for antiviral drugs in the virus replication cycle?
Which strategy involves preventing virus entry by using neutralizing antibodies and receptor occupation?
Which strategy involves preventing virus entry by using neutralizing antibodies and receptor occupation?
What is a characteristic of coronaviruses?
What is a characteristic of coronaviruses?
Where does the assembly of virions take place?
Where does the assembly of virions take place?
What is an advantage of narrow spectrum antivirals?
What is an advantage of narrow spectrum antivirals?
What is a disadvantage of broad spectrum antivirals?
What is a disadvantage of broad spectrum antivirals?
What is an important role of non-enveloped viruses during penetration of host membranes?
What is an important role of non-enveloped viruses during penetration of host membranes?
What is a key strategy for viruses to pass through the nuclear membrane?
What is a key strategy for viruses to pass through the nuclear membrane?
What do enveloped virus particles acquire during budding into intracellular membrane structures?
What do enveloped virus particles acquire during budding into intracellular membrane structures?
What may be targeted by antiviral strategies aiming to interfere with cellular processes for internalization?
What may be targeted by antiviral strategies aiming to interfere with cellular processes for internalization?
What happens when the viral RNA polymerase reaches the end of a transcription-regulating sequence (TRS)?
What happens when the viral RNA polymerase reaches the end of a transcription-regulating sequence (TRS)?
Where does the assembly of virions take place?
Where does the assembly of virions take place?
What role do M and E proteins play in the formation of virus envelopes?
What role do M and E proteins play in the formation of virus envelopes?
What is the function of the C-terminal cytoplasmic tail of M protein?
What is the function of the C-terminal cytoplasmic tail of M protein?
Where do virus particles form by budding?
Where do virus particles form by budding?
1.7
1.7
Study Notes
Virus Replication and Antiviral Strategies
- Non-enveloped viruses penetrate host membranes without lysis or rupture
- Viruses utilize cellular transport systems for efficient transport to the cytosol
- Many DNA viruses use the nucleus for replication and can establish latency
- Strategies for viruses to pass through the nuclear membrane
- Various ways for viruses to enter the nucleus, including during mitosis
- Every step in the virus replication cycle is a target for antiviral drugs
- Different ways to prevent virus entry, including neutralizing antibodies and receptor occupation
- Specific inhibitors and agents used to interfere with cellular processes for internalization
- Antiviral strategies targeting membrane fusion and uncoating of capsids
- Advantages and disadvantages of narrow and broad spectrum antivirals
- Characteristics of coronaviruses, including structure and genome
- Overview of the history, impact, and characteristics of SARS and COVID-19
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Description
Test your knowledge about the structure of coronaviruses and their envelope proteins. Learn about nucleocapsids, viral RNA, helical nucleocapsid, and envelope proteins like spike (S) and membrane (M).
