RNA Interference (27) Flashcards
How is the cellular response to viral RNA different in nematodes, arthropods and plants as opposed to chordates?
a. Nematodes, arthropods and plants use a protein-mediated response pathway and express ISGs
b. In terms of functional ISGs, nematodes, arthropods and plants only produce PKR
c. Nematodes, arthropods and plants directly generate viRNAs using RNA PAMPs
d. Nematodes, arthropods and plants rely on the action of RISC to produce interferon
c. Nematodes, arthropods and plants directly generate viRNAs using RNA PAMPs
What is a feature of siRNAs?
a. They are used in RNA interference, but no post-transcriptional gene silencing
b. They are 21nt long and have 2 nucleotide long tails at each 3’ end
c. They prevent the expression of RNA with the same sequence
d. siRNA contains an imperfectly duplexed double helix
b. They are 21nt long and have 2 nucleotide long tails at each 3’ end
Which is not a 21-27 nt small RNA?
a. siRNA
b. rasi RNA
c. miRNA
d. tRNA
d. tRNA
What happens during the processing of siRNA?
a. TRBP associates with DICER and assembles the guide strand into RISC
b. DICER acts as an endonuclease to slice complimentary RNA
c. Long dsRNA is first processed by the RISC
d. The strand of RNA with the most tightly base paired 5’ end becomes the guide strand in the RISC
a. TRBP associates with DICER and assembles the guide strand into RISC
What is correct about RNA Induced Transcriptional Silencing?
a. It can guide DNA acetylation
b. It can silence RNA viruses only
c. It is an epigenetic control method
d. It has been detected for HSV Inverted Repeats
c. It is an epigenetic control method
In mammals, long dsRNA:
a. Can act as a siRNA to silence PKR expression
b. Can lead to pathways that cause translational arrest
c. Can have RITs activity and silence DNA viruses
d. Cannot be detected by the protein based adaptive immune system
b. Can lead to pathways that cause translational arrest
What is NOT a feature of dsRNA genetic immunity in mammals?
a. Humans have a processing pathway for small RNAS but lack an RdRp
b. Mammalian sRNAs (miRNAs) are perfectly duplexed and cleave viral RNA
c. miRNAs in mammals act with the mRNA to arrest translation
d. Human miRNA can maintain viral latency
b. Mammalian sRNAs (miRNAs) are perfectly duplexed and cleave viral RNA
What is correct about miRNAs?
a. They are 22nt perfectly duplexed RNAs
b. They are only present in prokaryotes
c. After interacting with Dicer, a pre-miRNA is produced
d. The target sequence can be hard to predict due to wobble
d. The target sequence can be hard to predict due to wobble
Which would not be targeted by miRNA to suppress gene expression?
a. Protein translation
b. Nascent peptide formation during translation
c. RNA splicing
d. mRNA transcription
c. RNA splicing
Which virus typically makes a large amount of viral encoded miRNA?
a. Picornavirus
b. Herpesvirus
c. Poxvirus
d. Calicivirus
b. Herpesvirus
Which is correct about primate foamy virus?
a. Viral Tas can inhibit cellular RNAi
b. Viral replication is enhanced by miR-32
c. miR-122 represses viral replication
d. The virus avoids RNAi by having a DNA genome
a. Viral Tas can inhibit cellular RNAi
The Adenoviral VA1 pol III RNA:
a. Activates cellular Dicer
b. Phosphorylates PKR
c. Blocks nuclear export of pre-miRNAs
d. Lacks complex structure
c. Blocks nuclear export of pre-miRNAs
What does SV40 miRNA do?
a. It targets T proteins and promotes the early-late gene expression switch
b. It’s activity can promote apoptosis
c. It is only active during late gene expression
d. CTL killing is avoided as it allows early gene expression to remain constant and stable
a. It targets T proteins and promotes the early-late gene expression switch
What is NOT a feature of HIV TRBP?
a. It enhances miRNA biogenesis
b. It promotes PKR activity
c. It is a Dicer cofactor
d. It enhances the translation of HIV transcripts
b. It promotes PKR activity
What is correct about APOBEC3?
a. It targets and degrades HIV Vef
b. It can be inhibited by the reverse transciprtase activity of lentivirus
c. It targets the viral genome when it is in the ssRNA form
d. It is a cytidine deaminase that causes lethal G to A hypermutations of the viral genome
d. It is a cytidine deaminase that causes lethal G to A hypermutations of the viral genome
