相关实验视频
Updated: Feb 10, 2026
02:31
Phase Transitions and Effect of Intermolecular Forces
23.3K
线虫转接所需的拼接领导RNP的新组件用于线虫转接
John A Denker1, David M Zuckerman, Patricia A Maroney
1Center for RNA Molecular Biology, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, Ohio 44106, USA.
Nature
|June 7, 2002
概括
研究人员确定了两种新型蛋白质,这些蛋白质对于线虫中的拼接领导者 (SL) 跨拼接至关重要. 这些蛋白质对于这种独特的RNA处理至关重要,但对于标准的cis-splicing并非如此.
科学领域:
- 分子生物学分子生物学
- 处理RNA处理RNA处理
- 单核生物基因表达的表达方式
背景情况:
- 在线虫等较低的真核生物中,预信使RNA (mRNA) 的成熟利用拼接的领导者 (SL) 添加转拼.
- 这一过程将一个常见的5'外因子 (SL) 连接到各种前mRNA的5'-最多的外因子.
- 线虫SL是由特定的SLRNA衍生而来的,其结构类似于cis-spliceosomal U小核RNAs (snRNAs).
研究的目的:
- 为了净化和表征SL小核核核糖核蛋白 (snRNP) 参与线虫转接.
- 识别和确定SL RNP独特的蛋白质的功能.
- 阐明这些蛋白质促进SL转接的机制.
主要方法:
- 对SL RNP复合体的净化和特征.
- 使用重组蛋白质进行免疫减弱和复制试验.
- 对SL转与常规 cis-splicing 的蛋白质需求的分析.
主要成果:
- SL RNP 包含核心 Sm 蛋白质以及两个独特的蛋白质 (M(r) 175K 和 30K).
- 两种M(r) 175K和30K蛋白都对SL转接是必不可少的.
- 这些蛋白质不需要用于传统的 cis-splicing 或其他形式的 trans-splicing.
结论:
- 175K和30K的M(r) 蛋白质是首次发现的唯一参与SL转接的因素.
- 这些蛋白质可能在一个跨拼接的特定蛋白质相互作用网络中起作用.
- 这种网络类似于cis-splicing交叉-intron桥梁复合体.
相关概念视频
Phase Transitions
23.3K
Whether solid, liquid, or gas, a substance's state depends on the order and arrangement of its particles (atoms, molecules, or ions). Particles in the solid pack closely together, generally in a pattern. The particles vibrate about their fixed positions but do not move or squeeze past their neighbors. In liquids, although the particles are closely spaced, they are randomly arranged. The position of the particles are not fixed—that is, they are free to move past their neighbors to...
23.3K
Properties of Transition Metals
30.0K
Transition metals are defined as those elements that have partially filled d orbitals. As shown in Figure 1, the d-block elements in groups 3–12 are transition elements. The f-block elements, also called inner transition metals (the lanthanides and actinides), also meet this criterion because the d orbital is partially occupied before the f orbitals.
30.0K
Cooperative Allosteric Transitions
8.8K
Cooperative allosteric transitions can occur in multimeric proteins, where each subunit of the protein has its own ligand-binding site. When a ligand binds to any of these subunits, it triggers a conformational change that affects the binding sites in the other subunits; this can change the affinity of the other sites for their respective ligands. The ability of the protein to change the shape of its binding site is attributed to the presence of a mix of flexible and stable segments in the...
8.8K
Phase Transitions: Vaporization and Condensation
21.5K
The physical form of a substance changes on changing its temperature. For example, raising the temperature of a liquid causes the liquid to vaporize (convert into vapor). The process is called vaporization—a surface phenomenon. Vaporization occurs when the thermal motion of the molecules overcome the intermolecular forces, and the molecules (at the surface) escape into the gaseous state. When a liquid vaporizes in a closed container, gas molecules cannot escape. As these gas phase molecules...
21.5K
Phase Transitions: Sublimation and Deposition
20.3K
Some solids can transition directly into the gaseous state, bypassing the liquid state, via a process known as sublimation. At room temperature and standard pressure, a piece of dry ice (solid CO2) sublimes, appearing to gradually disappear without ever forming any liquid. Snow and ice sublimate at temperatures below the melting point of water, a slow process that may be accelerated by winds and the reduced atmospheric pressures at high altitudes. When solid iodine is warmed, the solid sublimes...
20.3K
Phase Transitions: Melting and Freezing
15.2K
Heating a crystalline solid increases the average energy of its atoms, molecules, or ions, and the solid gets hotter. At some point, the added energy becomes large enough to partially overcome the forces holding the molecules or ions of the solid in their fixed positions, and the solid begins the process of transitioning to the liquid state or melting. At this point, the temperature of the solid stops rising, despite the continual input of heat, and it remains constant until all of the solid is...
15.2K