SMAD蛋白质控制DROSHA介导的微RNA成熟过程
Brandi N Davis1, Aaron C Hilyard, Giorgio Lagna
1Department of Biochemistry, Tufts University School of Medicine, Boston, Massachusetts 02111, USA.
Nature
|June 13, 2008
概括
转化生长因子β (TGF-β) 和骨形态遗传蛋白 (BMP) 信号迅速增加微RNA-21 (miR-21) 水平. 这增强了血管光滑肌肉细胞收缩,通过降低PDCD4的调节,PDCD4是收缩基因的负调节器.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 生物化学 生物化学
背景情况:
- 微RNAs (miRNAs) 调节基因表达,但对它们的生物发生的控制尚不清楚.
- 转化生长因子β (TGF-β) 和骨形态遗传蛋白 (BMP) 信号通路对于血管发育和恒温至关重要.
- 失调的miRNA表达与癌症和心血管疾病等疾病有关.
研究的目的:
- 研究微RNA在TGF-β和BMP诱导的血管光滑肌细胞表型中的作用.
- 阐明TGF-β和BMP信号调节miRNA生物发生的机制.
主要方法:
- 定量实时PCR测量miRNA和基因表达.
- 西方涂抹测试以评估蛋白质水平.
- 免疫沉试验用于研究蛋白质-RNA相互作用.
主要成果:
- TGF-β和BMP信号传导通过miR-21诱导血管光滑肌肉细胞收缩.
- miR-21直接降低PDCD4的调节,PDCD4是平滑肌肉收缩基因的抑制剂.
- TGF-β和BMP信号增强成熟的miR-21的产生通过后转录处理的pri-miR-21的DROSHA复合体.
- SMAD蛋白和p68/DDX5被招募到primiR-21,以SMAD4独立的方式促进处理.
结论:
- TGF-β和BMP信号通过miR-21调节血管光滑肌肉细胞表型.
- 干特异性SMAD蛋白在转录后的水平上控制miRNA生物发生.
- 这种机制突出了TGF-β和BMP信号传输中的SMAD4独立的调节途径.
相关概念视频
MicroRNAs
MicroRNA (miRNA) are short, regulatory RNA transcribed from introns—non-coding regions of a gene—or intergenic regions—stretches of DNA present between genes. Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After the pre-miRNA ends...
MicroRNAs
MicroRNA (miRNA) are short, regulatory RNA transcribed from introns—non-coding regions of a gene—or intergenic regions—stretches of DNA present between genes. Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After the pre-miRNA ends...
siRNA - Small Interfering RNAs
Small interfering RNAs, or siRNAs, are short regulatory RNA molecules that can silence genes post-transcriptionally, as well as the transcriptional level in some cases. siRNAs are important for protecting cells against viral infections and silencing transposable genetic elements.
In the cytoplasm, siRNA is processed from a double-stranded RNA, which comes from either endogenous DNA transcription or exogenous sources like a virus. This double-stranded RNA is then cleaved by the ATP-dependent...
In the cytoplasm, siRNA is processed from a double-stranded RNA, which comes from either endogenous DNA transcription or exogenous sources like a virus. This double-stranded RNA is then cleaved by the ATP-dependent...
piRNA - Piwi-interacting RNAs
PIWI-interacting RNAs, or piRNAs, are the most abundant short non-coding RNAs. More than 20,000 genes have been found in humans that code for piRNAs while only 2000 genes have been found for miRNAs. piRNAs can act at the transcriptional and post-transcriptional levels and have a vital role in silencing transposable elements present in germ cells. They are also involved in epigenetic silencing and activation. Previously, they were thought to function only in germ cells but new evidence suggests...
Experimental RNAi
RNA interference (RNAi) is a cellular mechanism that inhibits gene expression by suppressing its transcription or activating the RNA degradation process. The mechanism was discovered by Andrew Fire and Craig Mello in 1998 in plants. Today, it is observed in almost all eukaryotes, including protozoa, flies, nematodes, insects, parasites, and mammals. This precise cellular mechanism of gene silencing has been developed into a technique that provides an efficient way to identify and determine the...
MicroRNAs
MicroRNA (miRNA) are short, regulatory RNA transcribed from introns (non-coding regions of a gene) or intergenic regions (stretches of DNA present between genes). Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself, forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After the pre-miRNA...


