概括
腺三酸盐 (ATP) 推动40S核糖体子单元沿信使RNA (mRNA) 的迁移. 如果没有ATP,这些子单元就会在mRNA附近停滞.
科学领域:
- 分子生物学分子生物学
- 生物化学 生物化学
- 遗传学 是一个遗传学.
背景情况:
- 细胞转化启动涉及40S核糖体亚单元与mRNA结合.
- 扫描模型建议40S子单元沿着mRNA移动以找到起始编码子.
- 在这个扫描过程中ATP的作用仍然不完全理解.
研究的目的:
- 为了研究40S核糖体亚单元在mRNA上迁移的ATP的要求.
- 提供支持或反对ATP依赖的翻译启动扫描模型的证据.
主要方法:
- 开发了两种测定方法:两步排水试验和3'末端标记的mRNA保护试验.
- 使用了reovirusmRNA和体马赛克病毒mRNA与小麦胚芽核糖体.
- 采用抗生素edeine来抑制进一步的核糖体附着和hexokinase来耗尽ATP.
主要成果:
- 添加ATP使预先形成的40S亚单元-mRNA复合物的解离成为可能 (流失试验).
- 40S子单元以ATP依赖的方式迁移到标记mRNA的3'端.
- ATP的耗尽阻止了40S子单元的迁移,将它们困在5'终端附近.
结论:
- 在mRNA上40S核糖体子单元的迁移是一个依赖ATP的过程.
- 这些发现支持扫描模型,预测ATP对于向启动符号移动至关重要.
- 由于ATP的耗尽,40S子单元会在AUG编码子上游积累.
相关概念视频
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 AssemblyRibosomes 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 the...
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 AssemblyRibosomes 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 the...
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...
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...