无意中介的衰变控制了先天免疫感知中的负反循环
Simon Boudreault1, Yahira Rivera-Lopez1, Max B Ferretti1
1Department of Biochemistry and Biophysics, University of Pennsylvania, Philadelphia, PA 19104.
概括
无意中介衰变 (NMD) 在病毒感染期间抑制dRNA传感,减少干扰素的产生. 这种NMD抑制作为一个负反循环,控制病毒dRNA水平和塑造先天免疫反应.
科学领域:
- 分子生物学分子生物学
- 免疫学 免疫学 免疫学
- 病毒学 病毒学
背景情况:
- 无意中介衰变 (NMD) 降解异常转录与过早终止的代码.
- 在生理条件下,NMD调节基因表达和同位素丰富度.
- 在病毒感染中NMD的作用是复杂的,表现出抗病毒和前病毒活动.
研究的目的:
- 调查NMD在病毒感染期间对双链RNA (dsRNA) 传感的参与.
- 澄清NMD的抗病毒与抗病毒作用之间的差异.
- 确定NMD抑制对先天免疫信号传递的影响.
主要方法:
- 利用EIF4A2外基子10B的纳入作为NMD调节病毒感染期间异形积累的模型.
- 评估了dSRNA传感对NMD活动的影响.
- 测量了干扰素β (IFN-β) 诱导,干扰素刺激的基因表达和PKR和RNaseL的激活.
- 评估IRF3酸化和核转位.
- 量化dsrna含量和评估巴基斯坦诱导的细胞死亡.
主要成果:
- dsRNA传感抑制了NMD,与翻译阻塞相关.
- RNaseL的激活主要驱动NMD的抑制,在没有RNaseL的情况下,PKR参与.
- 抑制NMD限制IFN-β和干扰素刺激的基因诱导,在IRF3激活之前.
- 通过降低dRNA水平,NMD抑制降低了PKR和RNaseL的激活和巴基斯坦诱导的细胞死亡.
- 通过调节dRNA负载,NMD似乎直接控制dRNA传感.
结论:
- 在dSRNA感知时的NMD抑制会在先天免疫中产生负反循环.
- 这种反机制塑造了dSRNA感知途径和病毒感染期间的先天免疫反应.
- 在调节宿主对病毒dsRNA的反应方面,NMD起着至关重要的作用.
相关概念视频
Nonsense-mediated mRNA Decay
3.3K
3.3K
Nonsense-mediated mRNA Decay
11.7K
The Upf proteins that carry out nonsense-mediated decay (NMD) are found in all eukaryotic organisms, including humans. Each protein has an individual role, but they need to work in collaboration. Upf1 is an ATP-dependent RNA helicase that unwinds the RNA helix. Because Upf1 can unwind any RNA, Upf2 and Upf3 are required to help Upf1 discriminate between nonsense and normal mRNAs.
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...
11.7K
Nuclear Export of mRNA
8.7K
Before mRNAs are exported to the cytoplasm, it is crucial to check each mRNA for structural and functional integrity. Eukaryotic cells use several different mechanisms, collectively known as mRNA surveillance, to look for irregularities in mRNAs. Irregular or aberrant mRNA are rapidly degraded by various enzymes. If a defective mRNA escapes the surveillance, it would be translated into a protein which would either be non-functional or not function properly. One of the primary irregularities in...
8.7K
Cell Signaling Feedback Loops
7.2K
Positive and negative feedback loops are crucial for regulating biological signaling systems. These feedback loops are processes that connect output signals to their inputs.
Negative feedback loops
Most signaling systems have negative feedback loops that can perform different functions such as output limiter, and adaptation.
Output limiter
Upon receiving an input signal, the cellular response rapidly increases until a threshold is reached. Beyond this threshold, a negative feedback loop...
Negative feedback loops
Most signaling systems have negative feedback loops that can perform different functions such as output limiter, and adaptation.
Output limiter
Upon receiving an input signal, the cellular response rapidly increases until a threshold is reached. Beyond this threshold, a negative feedback loop...
7.2K
NF-κB-dependent Signaling Pathway
9.8K
The transcription factor NF-κB was discovered in 1986 in the lab of Nobel laureate Professor David Baltimore, for its interaction with the immunoglobulin light chain enhancer in B-cells. After more than three decades of study, it is now evident that NF-κB regulates the expression of over 100 genes. Most of these genes play an essential role in the innate and adaptive immune responses as well as the inflammatory responses of animals.
NF-κB-dependent Signaling Mechanism
The...
NF-κB-dependent Signaling Mechanism
The...
9.8K
RNA Interference
27.8K
RNA interference (RNAi) is a process in which a small non-coding RNA molecule blocks the post-transcriptional expression of a gene by binding to its messenger RNA (mRNA) and preventing the protein from being translated.
This process occurs naturally in cells, often through the activity of genomically-encoded microRNAs. Researchers can take advantage of this mechanism by introducing synthetic RNAs to deactivate specific genes for research or therapeutic purposes. For example, RNAi could be used...
This process occurs naturally in cells, often through the activity of genomically-encoded microRNAs. Researchers can take advantage of this mechanism by introducing synthetic RNAs to deactivate specific genes for research or therapeutic purposes. For example, RNAi could be used...
27.8K


