U3小核核核核糖核蛋白在前核体RNA处理的第一步中起作用
1Human Genetics Program, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
Cell
|March 23, 1990
概括
U3小核核核核糖核蛋白 (snRNP) 对于哺乳动物核糖核糖核蛋白 (rRNA) 合成的初始步骤至关重要. 这项研究确定了U3 snRNP.
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 是一个遗传学.
背景情况:
- 核糖体生物发生是一个基本的细胞过程,涉及到前体核糖体RNA (pre-rRNA) 的成熟.
- 哺乳动物前rRNA成熟的初始处理步骤发生在5'外部转录间隔的5'端.
- 这种早期裂变事件所涉及的精确分子机械和因素仍然不完全理解.
研究的目的:
- 为了确定特定的小核核核核糖核蛋白 (snRNP) 负责哺乳动物前rRNA成熟的第一个裂变事件.
- 阐明确定 snRNP 的前rRNA 识别和处理背后的分子机制.
- 在核组织和核糖体转录的背景下研究U3 snRNP的作用.
主要方法:
- 利用小鼠细胞提取物研究前rRNA处理.
- 采用微菌核酶预处理来评估加工活动.
- 针对U3,U8和U13snRNP (抗纤维素素) 的使用自抗体,用于耗尽和免疫沉研究.
- 应用原生凝电泳和北方涂抹来分析加工中间体.
- 通过核酸导向RNAase H治疗研究了特定的U3 snRNP参与.
主要成果:
- 微球菌核酶预处理取消了最初的rRNA前处理活动.
- 抗纤维素抗体削弱了处理活性和免疫沉的rRNA基质和产品.
- 通过多种实验方法证实了U3 snRNP在加工事件中的具体参与.
- 针对U3 snRNP的Oligonucleotide导向RNAase H治疗取消了加工活动.
结论:
- U3 snRNP在哺乳动物前rRNA的初始5'裂变中发挥着关键和特定的作用.
- 这一发现为U3 snRNP.的前rRNA识别的分子基础提供了见解.
- 这项研究有助于了解核细胞snRNP在核糖体生物发生和核细胞组织中的功能.
相关概念视频
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02:01pre-mRNA Processing
In eukaryotic cells, transcripts made by RNA polymerase are modified and processed before exiting the nucleus. Unprocessed RNA is called precursor mRNA or pre-mRNA to distinguish it from mature mRNA.
Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a “cap” to the 5’ end of the growing transcript. In this process, a 5’ phosphate is replaced by modified guanosine that has a methyl group attached to it (7-Methyl guanosine). This 5’ cap helps the...
Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a “cap” to the 5’ end of the growing transcript. In this process, a 5’ phosphate is replaced by modified guanosine that has a methyl group attached to it (7-Methyl guanosine). This 5’ cap helps the...
02:01Pre-mRNA Processing
In eukaryotic cells, transcripts made by RNA polymerase are modified and processed before exiting the nucleus. Unprocessed RNA is called precursor mRNA or pre-mRNA to distinguish it from mature mRNA.
Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a “cap” to the 5’ end of the growing transcript. In this process, a 5’ phosphate is replaced by modified guanosine that has a methyl group attached to it (7-Methyl guanosine). This 5’ cap helps the...
Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a “cap” to the 5’ end of the growing transcript. In this process, a 5’ phosphate is replaced by modified guanosine that has a methyl group attached to it (7-Methyl guanosine). This 5’ cap helps the...
02:53Ribosomal RNA Synthesis
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Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
02:53Ribosomal RNA Synthesis
Ribosome synthesis is a highly complex and coordinated process involving more than 200 assembly factors. The synthesis and processing of ribosomal components occurs not only in the nucleolus but also in the nucleoplasm and the cytoplasm of eukaryotic cells.
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
Ribosome biogenesis begins with the synthesis of 5S and 45S pre-rRNAs by distinct RNA polymerases. The primary transcripts are extensively processed and modified before they are bound and folded by ribosomal proteins and assembly factors,...
01:27Ribosomes
Ribosomes translate genetic information encoded by messenger RNA (mRNA) into proteins. Both prokaryotic and eukaryotic cells have ribosomes. Cells that synthesize large quantities of protein—such as secretory cells in the human pancreas—can contain millions of ribosomes.
Ribosome Structure and Assembly
Ribosomes are composed of ribosomal RNA (rRNA) and proteins. In eukaryotes, rRNA is transcribed from genes in the nucleolus—a part of the nucleus that specializes in ribosome production. Within...
Ribosome Structure and Assembly
Ribosomes are composed of ribosomal RNA (rRNA) and proteins. In eukaryotes, rRNA is transcribed from genes in the nucleolus—a part of the nucleus that specializes in ribosome production. Within...