Podcast
Questions and Answers
What is the role of miRNAs in posttranscriptional gene silencing?
What is the role of miRNAs in posttranscriptional gene silencing?
Which protein family plays a central role in RNA silencing processes as essential catalytic components of RISC?
Which protein family plays a central role in RNA silencing processes as essential catalytic components of RISC?
What is the main function of the Argonaute protein in the RNA-induced silencing complex (RISC)?
What is the main function of the Argonaute protein in the RNA-induced silencing complex (RISC)?
What phenomenon is associated with gene silencing through RNA interference?
What phenomenon is associated with gene silencing through RNA interference?
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In Arabidopsis, what happens when there is a mutation in the AGO1 gene, a key component of RISC?
In Arabidopsis, what happens when there is a mutation in the AGO1 gene, a key component of RISC?
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What is the term coined by researchers to describe the phenomenon of double-stranded RNA (dsRNA) successfully silencing a targeted gene?
What is the term coined by researchers to describe the phenomenon of double-stranded RNA (dsRNA) successfully silencing a targeted gene?
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What is the similarity between miRNA and siRNA in terms of mRNA cleavage?
What is the similarity between miRNA and siRNA in terms of mRNA cleavage?
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Which molecule is responsible for processing double-stranded RNA (dsRNA) to produce small interfering RNAs (siRNAs) in the RNA interference (RNAi) pathway?
Which molecule is responsible for processing double-stranded RNA (dsRNA) to produce small interfering RNAs (siRNAs) in the RNA interference (RNAi) pathway?
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In the RNA interference (RNAi) mechanism, which protein manipulates small interfering RNAs (siRNAs) to induce gene silencing?
In the RNA interference (RNAi) mechanism, which protein manipulates small interfering RNAs (siRNAs) to induce gene silencing?
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Which of the following organisms does NOT exhibit post-transcriptional gene silencing (PTGS) through RNA interference (RNAi)?
Which of the following organisms does NOT exhibit post-transcriptional gene silencing (PTGS) through RNA interference (RNAi)?
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Which type of RNA successfully silenced a targeted gene better than antisense RNA in the experiment mentioned?
Which type of RNA successfully silenced a targeted gene better than antisense RNA in the experiment mentioned?
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What is the role of double-stranded RNA (dsRNA) in inducing interference of a mRNA target like Mex-3 in the nematode C.elegans?
What is the role of double-stranded RNA (dsRNA) in inducing interference of a mRNA target like Mex-3 in the nematode C.elegans?
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What is the main role of small interfering RNAs (siRNAs) in gene expression regulation?
What is the main role of small interfering RNAs (siRNAs) in gene expression regulation?
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Which pathway produces microRNAs (miRNAs) that can silence complementary target genes?
Which pathway produces microRNAs (miRNAs) that can silence complementary target genes?
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What are the two mechanisms involved in gene silencing by small RNAs?
What are the two mechanisms involved in gene silencing by small RNAs?
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Who discovered post-transcriptional gene silencing (PTGS) and in which organism was it first discovered?
Who discovered post-transcriptional gene silencing (PTGS) and in which organism was it first discovered?
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Which enzymes of the flavonoid/anthocyanin pathway were involved in the discovery of PTGS in petunia?
Which enzymes of the flavonoid/anthocyanin pathway were involved in the discovery of PTGS in petunia?
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In the context of RNA interference, what is the function of Dicer?
In the context of RNA interference, what is the function of Dicer?
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Study Notes
Post-transcriptional Gene Silencing
- miRNAs play a crucial role in post-transcriptional gene silencing through RNA interference (RNAi)
- The Argonaute protein family plays a central role in RNA silencing processes as essential catalytic components of RISC (RNA-induced silencing complex)
RNA-induced Silencing Complex (RISC)
- Argonaute protein is the main catalytic component of RISC, responsible for mRNA cleavage
- RISC is responsible for recognizing and degrading target mRNA complementary to small RNAs
RNA Interference (RNAi)
- RNAi is associated with gene silencing through the degradation of target mRNA
- Double-stranded RNA (dsRNA) is responsible for inducing interference of a target mRNA
- The term "RNA interference" was coined to describe the phenomenon of dsRNA successfully silencing a targeted gene
MicroRNAs (miRNAs) and Small Interfering RNAs (siRNAs)
- Both miRNAs and siRNAs are involved in gene expression regulation through RNAi
- miRNAs are processed from hairpin structures, while siRNAs are processed from double-stranded RNA
- Both miRNAs and siRNAs induce gene silencing through mRNA cleavage
Processing of double-stranded RNA (dsRNA)
- Dicer is responsible for processing dsRNA to produce siRNAs
- The RNAi pathway produces miRNAs that can silence complementary target genes
Gene Silencing Mechanisms
- Two mechanisms involved in gene silencing by small RNAs are: mRNA cleavage and translation inhibition
- PTGS is a mechanism of gene silencing that occurs in many organisms, including plants and animals
Discovery of PTGS
- Post-transcriptional gene silencing (PTGS) was first discovered in petunia
- The discovery of PTGS involved the silencing of enzymes in the flavonoid/anthocyanin pathway
- Andrew Fire and Craig Mello discovered PTGS in the nematode Caenorhabditis elegans (C. elegans)
Organisms exhibiting PTGS
- Not all organisms exhibit PTGS through RNAi; Neurospora crassa is an example of an organism that does not exhibit PTGS
- PTGS has been observed in many organisms, including plants, animals, and fungi
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Description
Test your knowledge on microRNAs (miRNA) and small interfering RNAs (siRNA) pathways, including their functions in posttranscriptionally repressing target genes. Learn about the Argonaute protein family's role in RNA silencing processes.