Video Experimental Relacionado
Updated: May 16, 2026
08:33
Ubiquitin Chain Analysis by Parallel Reaction Monitoring
Published on: June 17, 2020
La conformación de la cadena de ubiquitina regula el reconocimiento y la actividad de las proteínas que interactúan
Yu Ye1, Georg Blaser, Mathew H Horrocks
1Division of Protein and Nucleic Acids Chemistry, MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK.
Nature
|December 4, 2012
Resumen
La ubiquitinación de proteínas implica cadenas dinámicas de ubiquitina que existen en distintas conformaciones. Estos estados preexistentes son reconocidos por las proteínas que interactúan, influyendo en la regulación biológica.
Área de la Ciencia:
- La bioquímica es la bioquímica.
- Biología Molecular Biología Molecular
- Biología Estructural Biología estructural.
Sus antecedentes:
- Los mecanismos de reconocimiento de proteínas están bien estudiados para las proteínas de un solo dominio, pero menos para los sistemas dinámicos multidominio.
- Las cadenas de ubiquitina son sistemas multidominio críticos reconocidos por diversas proteínas que interactúan con la ubiquitina.
- Las conformaciones de la cadena de ubiquitina difieren entre los estados aislados y los complejos unidos a proteínas, lo que sugiere flexibilidad o remodelación.
Objetivo del estudio:
- Para investigar los estados conformacionales de diferentes enlaces de la cadena de la ubiquitina en solución.
- Para determinar si las proteínas que interactúan con la ubiquitina seleccionan conformaciones preexistentes o inducen remodelación.
- Comprender el papel de los equilibrios conformacionales en el reconocimiento y regulación de la cadena de ubiquitina.
Principales métodos:
- Se utilizó la transferencia de energía de resonancia de fluorescencia de molécula única (smFRET) para estudiar las conformaciones de la diubiquitina.
- Análisis de la diubiquitina ligada a Lys63-, Lys48- y Met1 en solución.
- Investigación de las interacciones entre la diubiquitina y los dominios de unión a la ubiquitina/deubiquitinasas (DUB).
Principales resultados:
- La diubiquitina ligada a Lys63- y Met1 existe en distintas conformaciones "abiertas" y "cerradas".
- Los dominios de unión a la ubiquitina y los DUB seleccionan estas conformaciones preexistentes.
- La diubiquitina ligada a Lys48 adopta predominantemente conformaciones compactas, y las DUB pueden remodelar estas cadenas.
- La interrupción de la interfaz de Lys48-diubiquitin altera la dinámica y la actividad DUB.
Conclusiones:
- Los equilibrios conformacionales en las cadenas de ubiquitina ofrecen una capa reguladora adicional en el sistema de ubiquitina.
- Conformaciones distintas de poliubiquitina ligada de manera diferente contribuyen a la especificidad de las proteínas que interactúan con la ubiquitina.
- Comprender estas dinámicas conformacionales es crucial para descifrar las vías de señalización de la ubiquitina.
Videos de Conceptos Relacionados
02:58Regulated Protein Degradation
It is vital to regulate the activity of enzymatic as well as non-enzymatic proteins inside the cell. This can be achieved either through creating a balance between their rate of synthesis and degradation or regulating the intrinsic activity of the protein. Both these regulation mechanisms play an essential role in the normal functioning of cells.
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
02:04Covalently Linked Protein Regulators
Proteins can undergo many types of post-translational modifications, often in response to changes in their environment. These modifications play an important role in the function and stability of these proteins. Covalently linked molecules include functional groups, such as methyl, acetyl, and phosphate groups, and also small proteins, such as ubiquitin. There are around 200 different types of covalent regulators that have been identified.
These groups modify specific amino acids in a protein.
These groups modify specific amino acids in a protein.
02:04Covalently Linked Protein Regulators
Proteins can undergo many types of post-translational modifications, often in response to changes in their environment. These modifications play an important role in the function and stability of these proteins. Covalently linked molecules include functional groups, such as methyl, acetyl, and phosphate groups, and also small proteins, such as ubiquitin. There are around 200 different types of covalent regulators that have been identified.
These groups modify specific amino acids in a protein.
These groups modify specific amino acids in a protein.
01:57Protein Complexes with Interchangeable Parts
Groups of proteins may form a complex where each protein in this complex has a different role in the overall execution of the complex’s function. Often some of the proteins in the complex can be replaced by a closely related variant to give a complex that contains many of the same components yet is functionally distinct.
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order to...
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order to...
01:13The Proteasome
Eukaryotic cells can degrade proteins through several pathways. One of the most important among these is the ubiquitin-proteasome pathway. It helps the cell eliminate the misfolded, damaged, or unwarranted cytoplasmic proteins in a highly specific manner.
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. This involves participation of a series of enzymes including— E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3 (ubiquitin...
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. This involves participation of a series of enzymes including— E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3 (ubiquitin...
02:18The Proteasome
Eukaryotic cells can degrade proteins through several pathways. One of the most important amongst these is the ubiquitin-proteasome pathway. It helps the cell eliminate the misfolded, damaged, or unwarranted cytoplasmic proteins in a highly specific manner.
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. A series of enzymes carry out the ubiquitination of the target proteins - E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. A series of enzymes carry out the ubiquitination of the target proteins - E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...