相关实验视频
Updated: Aug 18, 2026
14:57
Yeast As a Chassis for Developing Functional Assays to Study Human P53
Published on: August 4, 2019
概括
一个单一的基因突变通过改变p21蛋白质来改变人类膀癌细胞. 这种在位置12的甘氨酸到氨酸的变化破坏了核酸结合,影响了细胞生长.
科学领域:
- 分子生物学分子生物学
- 在瘤学瘤学.
- 结构生物学 结构生物学
背景情况:
- 由于特定的点突变,EJ和T24人类膀癌基因具有转变性质.
- 这种突变涉及关氨酸转化为胆氨酸,在编码的p21蛋白的位置12将甘氨酸变为氨酸.
- 正常的p21蛋白质结构强调了位于12位的甘氨酸的重要性.
研究的目的:
- 为了研究p21蛋白质中12位的甘氨酸的重要性的结构基础.
- 了解甘氨酸-氨酸突变如何影响p21蛋白功能和核酸结合.
- 介绍p21蛋白质核酸结合单元的结构模型.
主要方法:
- 对p21蛋白的逆转录病毒类似物进行序列分析.
- 人类p21的N端残留物与相关酶中已知的核酸结合单元的比较.
- 开发一个p21βααβα单元的三维模型.
主要成果:
- 人类p21蛋白的N端残留物折叠成一个类似于结构相关酶的βαβ单元,这表明它具有核酸结合作用.
- 生成了p21βααβα单元的三维模型.
- 该模型解释了为什么在位置12的甘氨酸是关键的,并且其被其他残留物取代会改变核酸结合特性.
结论:
- 位于12位的甘氨酸对于p21蛋白的正常核酸结合功能至关重要.
- 观察到的EJ和T24基因突变改变了这一关键残留物,导致蛋白质功能异常,并可能导致癌症转变.
- 结构建模为这种特定突变的功能后果提供了直接的解释.
相关概念视频
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01:49Conserved Binding Sites
Many proteins’ biological role depends on their interactions with their ligands, small molecules that bind to specific locations on the protein known as ligand-binding sites. Ligand-binding sites are often conserved among homologous proteins as these sites are critical for protein function.
Binding sites are often located in large pockets, and if their location on a protein’s surface is unknown, it can be predicted using various approaches. The energetic method computationally analyses the...
Binding sites are often located in large pockets, and if their location on a protein’s surface is unknown, it can be predicted using various approaches. The energetic method computationally analyses the...
02:04Covalently Linked Protein Regulators
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These groups modify specific amino acids in a protein.
These groups modify specific amino acids in a protein.
02:23Abnormal Proliferation
Under normal conditions, most adult cells remain in a non-proliferative state unless stimulated by internal or external factors to replace lost cells. Abnormal cell proliferation is a condition in which the cell's growth exceeds and is uncoordinated with normal cells. In such situations, cell division persists in the same excessive manner even after cessation of the stimuli, leading to persistent tumors. The tumor arises from the damaged cells that replicate to pass the damage to the daughter...
01:05Cancer-Critical Genes II: Tumor Suppressor Genes
Genes usually encode proteins necessary for the proper functioning of a healthy cell. Mutations can often cause changes to the gene expression pattern, thereby altering the phenotype.
When the function of certain critical genes, especially those involved in cell cycle regulation and cell growth signaling cascades, gets disrupted, it upsets the cell cycle progression. Such cells with unchecked cell cycles start proliferating uncontrollably and eventually develop into tumors.
Such genes that act...
When the function of certain critical genes, especially those involved in cell cycle regulation and cell growth signaling cascades, gets disrupted, it upsets the cell cycle progression. Such cells with unchecked cell cycles start proliferating uncontrollably and eventually develop into tumors.
Such genes that act...
01:05Cancer-Critical Genes II: Tumor Suppressor Genes
Genes usually encode proteins necessary for the proper functioning of a healthy cell. Mutations can often cause changes to the gene expression pattern, thereby altering the phenotype.
When the function of certain critical genes, especially those involved in cell cycle regulation and cell growth signaling cascades, gets disrupted, it upsets the cell cycle progression. Such cells with unchecked cell cycles start proliferating uncontrollably and eventually develop into tumors.
Such genes that act...
When the function of certain critical genes, especially those involved in cell cycle regulation and cell growth signaling cascades, gets disrupted, it upsets the cell cycle progression. Such cells with unchecked cell cycles start proliferating uncontrollably and eventually develop into tumors.
Such genes that act...