Question16 In RNA interference (RNAi), if a mutation in Ago2 prevents the production of a functional Ago2 enzyme, which ONE of the following outcomes is most likely? Select one alternative: Transport of double-stranded siRNA to RISC would be impaired Separation of double-stranded siRNA into single-stranded siRNA would not occur Long double-stranded RNA would not be processed into siRNA Single-stranded siRNA would be unable to guide RISC to specific mRNA targets ResetMaximum marks: 1 Flag question undefined单项选择题
A
Transport of double-stranded siRNA to RISC would be impaired
B
Separation of double-stranded siRNA into single-stranded siRNA would not occur
C
Long double-stranded RNA would not be processed into siRNA
D
Single-stranded siRNA would be unable to guide RISC to specific mRNA targets

Question

Question16 In RNA interference (RNAi), if a mutation in Ago2 prevents the production of a functional Ago2 enzyme, which ONE of the following outcomes is most likely? Select one alternative: Transport of double-stranded siRNA to RISC would be impaired Separation of double-stranded siRNA into single-stranded siRNA would not occur Long double-stranded RNA would not be processed into siRNA Single-stranded siRNA would be unable to guide RISC to specific mRNA targets ResetMaximum marks: 1 Flag question undefined单项选择题

A

Transport of double-stranded siRNA to RISC would be impaired

B

Separation of double-stranded siRNA into single-stranded siRNA would not occur

C

Long double-stranded RNA would not be processed into siRNA

D

Single-stranded siRNA would be unable to guide RISC to specific mRNA targets

BlackTom AI · Accepted Answer

Question restated: In RNA interference (RNAi), if a mutation in Ago2 prevents the production of a functional Ago2 enzyme, which ONE of the following outcomes is most likely? Options: 1) Transport of double-stranded siRNA to RISC would be impaired, 2) Separation of double-stranded siRNA into single-stranded siRNA would not occur, 3) Long double-stranded RNA would not be processed into siRNA, 4) Single-stranded siRNA would be unable to guide RISC to specific mRNA targets.

Option 1: Transport of ds-siRNA to RISC would be impaired. This option posits a defect in delivery of the double-stranded siRNA to the RISC complex. In the RNAi pathway, loading of siRNA onto RISC involves multiple components, but Ago2 specifically is the catalytic core that later participates in guide strand pairing and cleavage. A loss of Ago2 function does not inherently block the physical transport of ds-siRNA to RISC; other factors and chaperones can still deliver siRNA to RISC or loading can occur upstream of Ago2's catalytic action. Therefore this statement is not the most direct or likely consequence of Ago2 dysfunction.

Option 2: Separation of ds-siRNA into ss-siRNA would not occur. Proper RNAi requires the unwinding of the siRNA duplex to yield a single guide strand that can direct RISC to complementary mRNA targets. While Ago2 is the catalytic component that cleaves the passenger strand in perfectly matched siRNA duplexes in many organisms, the initial unwinding and strand separation can still occur via other mechanisms and factors, and the passenger-strand removal often relies on Ago2 activity. If Ago2 is nonfunctional, the unwinding and/or passenger-strand cleavage may be defective, leading to impaired generation of an active guide strand. This makes the absence of separation a plausible key consequence when Ago2 cannot function, making this option a strong candidate for the correct answer.

Option 3: Long dsRNA would not be processed into siRNA. Dicer is the enzyme responsible for processing long dsRNA into siRNA. While Ago2 plays a role downstream of Dicer in RISC, Ago2 dysfunction does not prevent Dicer from slicing long dsRNA into siRNA fragments. Therefore this option is incorrect because Dicer activity is independent of Ago2’s catalytic function.

Option 4: Single-stranded siRNA would be unable to guide RISC to specific mRNA targets. If Ago2 is nonfunctional, even if a single-stranded guide were available, it may not be loaded into a functional RISC or properly guided to targets due to compromised RISC activity. In practice, however, the fundamental issue stems from the inability to generate a proper guide strand through strand separation and loading steps that require Ago2. This option describes a downstream consequence that is plausible but does not as directly capture the primary bottleneck caused by loss of Ago2 catalytic function as described in the question.

In summary, Option 2 directly ties the consequence to the specific defect in Ago2: without functional Ago2, the separation (unwinding) of the siRNA duplex into a usable single guide strand would be impeded, which is the most coherent outcome given Ago2’s role in RISC activity and siRNA processing steps downstream of Dicer. Other options either misattribute a blocked step to Ago2’s absence (transport), rely on another enzyme’s activity (Dicer) not dependent on Ago2, or describe downstream effects that are less directly linked to the described mutation.

类似问题

What happens to the siRNA strands after the siRNA molecule is incorporated into the RISC complex?

The discovery of RNA interference (RNAi) led to its use in biotechnology and medicine. All of the following are examples of how RNAi could be used in biotechnology or medicine, EXCEPT ________.

Question at position 69 Which would result in mRNA degradation by siRNA/miRNA and RISC?many mismatchesa match with some mismatchesa perfect match

Question at position 36 True or False. If the RISC complex with siRNA or miRNA holds the mRNA, then translation is inhibited.TrueFalse

RNA interference using which form of RNA participates with RITS to enable modification of DNA to regulate gene expression by preventing transcription?

A scientist who is studying the XYZ gene in a eukaryotic model cell inserts an miRNA that is complementary to a portion of the XYZ mRNA found in the cell. What result would you predict?

Which enzyme is involved in generating small RNA duplexes from both miRNA and siRNA precursors?

更多留学生实用工具

智能学习助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单