概括
流感血素 (HA) 的疏水性碳酸终端序列对于其表面表达至关重要. 如果没有这些序列,HA就会分泌出来,并表现出改变的糖化.
科学领域:
- 病毒学 病毒学
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
背景情况:
- 流感血凝素 (HA) 对于病毒进入至关重要,也是疫苗的关键目标.
- 了解控制HA表面表达的分子机制对于病毒病原性研究至关重要.
研究的目的:
- 调查碳氧终端序列在流感病毒血素 (HA) 表面表达中的作用.
- 确定疏水性碳氧终端区域对于HA定位和功能的特定要求.
主要方法:
- 在血凝素基因中引入缺失,特别针对carboxy-terminal疏水区域.
- 灵长类细胞感染了携带被删除HA基因的复合SV40载体.
- 使用免疫光和红细胞吸附试验分析细胞表面表达.
- 对突变HA的多分析,包括用尼卡米辛和内糖酶H治疗的糖化研究.
主要成果:
- 缺少正常的疏水性碳酸末端序列的突变HA无法在细胞表面表达,无法吸附红细胞.
- 发现这些突变HA被分泌到细胞介质中.
- 在删除突变体中检测到细胞内切断的HA多.
- 细胞内和细胞外突变HA都被糖化,但与表面HA相比,对内葡萄糖酶H的敏感性有所改变.
结论:
- 流感血素的疏水性碳酸终端序列对于其在细胞表面的积累和保留至关重要.
- 这些序列的改变导致蛋白质的分泌和其糖化模式的变化.
- 这些发现为流感HA的翻译后修饰和贩运提供了关键的见解.
更多相关视频
相关概念视频
Leaky Scanning
During most eukaryotic translation processes, the small 40S ribosome subunit scans an mRNA from its 5' end until it encounters the first start AUG codon. The large 60S ribosomal subunit then joins the smaller one to initiate protein synthesis. The location of the translation initiation is largely determined by the nucleotides near the start codon as there may be multiple translation initiation sites present on the mRNA. Marilyn Kozak discovered that the sequence RCCAUGG (where R stands for...
Fluid Mosaic Model
Scientists identified the plasma membrane in the 1890s and its principal chemical components (lipids and proteins) by 1915. The model for plasma membrane structure, proposed in 1935 by Hugh Davson and James Danielli, was the first model to be widely accepted in the scientific community. The model was based on the plasma membrane's "railroad track" appearance in early electron micrographs. Davson and Danielli theorized that the plasma membrane's structure resembled a sandwich with the analogy of...
Membrane Carbohydrates
The plasma membrane is a dynamic barrier composed of lipids, proteins, and carbohydrates. It is the epicenter of many cellular processes required for cell growth and survival. Carbohydrates have unique structural and chemical properties that help the plasma membrane to carry out its functions effectively.
Membrane carbohydrates do not have any hydrophobic region and are exclusively located on the cell's outer surface. The addition of sugar molecules or glycosylation of proteins happens in...
Membrane carbohydrates do not have any hydrophobic region and are exclusively located on the cell's outer surface. The addition of sugar molecules or glycosylation of proteins happens in...
Insertion of Single-pass Transmembrane Proteins in the RER
Integral membrane proteins are proteins adhered to the lipid bilayer of a cell organelle or membrane. They can be of two types: transmembrane integral proteins that span the lipid bilayer and monotopic proteins that are attached to either side of the membrane but do not pass through it.
Integral transmembrane proteins possess transmembrane and extra membrane domains. The transmembrane domains are primarily made of 20-25 hydrophobic amino acids arranged in a helical secondary confirmation. These...
Integral transmembrane proteins possess transmembrane and extra membrane domains. The transmembrane domains are primarily made of 20-25 hydrophobic amino acids arranged in a helical secondary confirmation. These...
Influenza
Influenza is an acute, highly communicable viral disease that affects the respiratory tract and is responsible for seasonal epidemics worldwide. Influenza A is the most prevalent type associated with widespread outbreaks and is subtyped based on two surface glycoproteins: hemagglutinin (H) and neuraminidase (N), as in H1N1. These glycoproteins are essential for viral infectivity, transmission, and immune recognition. Transmission occurs primarily through respiratory droplets and contaminated...
Inhibitors Of Virion Release
Viral replication and dissemination rely on efficient mechanisms for host cell entry, genome replication, assembly, and release. Influenza viruses, such as types A and B, are negative-sense single-stranded RNA viruses with a segmented genome, that depend on two critical surface glycoproteins to carry out these processes: hemagglutinin (HA) and neuraminidase (NA). HA initiates infection by binding to sialic acid residues on the surface of host epithelial cells, facilitating receptor-mediated...


