蛋白质Aly将前传递 RNA 拼接与元动物中的核出口联系起来
1Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115, USA.
Nature
|October 3, 2000
概括
拼接增强了元动物中的信使RNA (mRNA) 出口. 蛋白质Aly通过结合拼接的mRNA来连接这些过程,促进其从核到细胞质的有效运输.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 遗传学 遗传学 是一个
背景情况:
- 甲基动物前传递 RNA (前mRNA) 含有通过剪接移除的内子.
- 剪接的mRNA从细胞核出口到细胞质.
- 连接拼接和mRNA出口的机制目前尚不清楚.
研究的目的:
- 为了研究结合mRNA前拼接和mRNA出口的机制.
- 确定涉及连接这两种基本细胞过程的因素.
主要方法:
- 艾利蛋白对不同信使核糖蛋白 (mRNP) 复合物的招募测定.
- 对Aly蛋白与拼接和未拼接的mRNA相关性的分析.
- 对Aly转运及其对mRNA vivo出口率的影响的调查.
- 艾利与剪接因子的同定位研究.
主要成果:
- 艾利,酵母mRNA出口因子Yralp的同类物,被专门招募到结合的mRNP中.
- 艾利与来自无内核mRNA或异质核RNP (hnRNP) 复合物的mRNP不结合.
- 艾利在结合体组装过程中被招募,并与结合的mRNP密切相关.
- Aly在细胞核和细胞质之间穿,其过度表达提高了mRNA出口率和效率.
- 艾利与核拼接因子共同定位,证实了依赖拼接的招募.
结论:
- 拼接对于元动物中有效的mRNA输出至关重要.
- 蛋白质Aly在拼接机械和mRNA出口途径之间起到关键作用.
- 艾利对结合的mRNP的招募有助于它们随后的出口到细胞质.
相关概念视频
01:32RNA Splicing
Splicing is the process by which eukaryotic RNA is edited before its translation into protein. The RNA strand transcribed from eukaryotic DNA is called the primary transcript. The primary transcripts that become mRNAs are called precursor messenger RNAs (pre-mRNAs). Eukaryotic pre-mRNA contains alternating sequences of exons and introns. Exons are nucleotide sequences that code for proteins, whereas introns are the non-coding regions. In RNA splicing, introns are removed and exons are bonded...
01:32RNA Splicing
Splicing is the process by which eukaryotic RNA is edited before its translation into protein. The RNA strand transcribed from eukaryotic DNA is called the primary transcript. The primary transcripts that become mRNAs are called precursor messenger RNAs (pre-mRNAs). Eukaryotic pre-mRNA contains alternating sequences of exons and introns. Exons are nucleotide sequences that code for proteins, whereas introns are the non-coding regions. In RNA splicing, introns are removed and exons are bonded...
02:31Nuclear Export of mRNA
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...
02:22Regulated mRNA Transport
In eukaryotes, transcription and translation are compartmentalized; an mRNA is first synthesized in the nucleus and then selectively transported to the cytoplasm for protein synthesis. Before transport, a pre-mRNA undergoes several steps of post-transcriptional modifications including splicing, 5' capping, and the addition of a poly-adenine tail. Various proteins bind to the pre-mRNA during these modifications. The mRNA transport takes place with the help of multiple proteins playing specific...
01:42Nuclear Export
The nucleus restricts several proteins within and allows others to pass. The restricted proteins possess a nuclear retention sequence or NRS, anchoring them to the nuclear lamins and preventing their transport to the cytosol. The non-restricted proteins, after their synthesis, are transported to their site of action, such as the cytosol or other organelles, with the help of nuclear export signals or NES.
NES are of three types- the canonical 10-residue long leucine-rich signal and other...
NES are of three types- the canonical 10-residue long leucine-rich signal and other...
02:31Nuclear Export of mRNA
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...