Video Experimental Relacionado
Updated: Jul 13, 2026
07:55
Analyzing Cell Surface Adhesion Remodeling in Response to Mechanical Tension Using Magnetic Beads
Published on: March 8, 2017
Bases estructurales para la activación de la vinculina en los sitios de adhesión celular
Constantina Bakolitsa1, Daniel M Cohen, Laurie A Bankston
1Program on Cell Adhesion, The Burnham Institute, 10901 North Torrey Pines Road, La Jolla, California 92037, USA.
Nature
|June 15, 2004
Resumen
La estructura de la proteína vinculina revela una conformación autoinhibida esencial para la regulación de la adhesión celular. Su vía de activación asegura una función precisa en las uniones celulares, vinculando la dinámica citoesquelética con las moléculas de adhesión.
Área de la Ciencia:
- Biología molecular y celular Biología molecular y celular.
- Biología Estructural Biología Estructural
- La biofísica es la biofísica.
Sus antecedentes:
- La vinculina es una proteína intracelular clave que regula la adhesión y la migración celular.
- Desempeña un papel crítico en la conexión del citoesqueleto de actina con los complejos de adhesión celular.
- La vinculina existe en un estado autoinhibido en el citosol.
Objetivo del estudio:
- Para determinar la estructura cristalina de la molécula completa de vinculina.
- Para dilucidar el mecanismo de autoinhibición y activación de la vinculina.
- Para entender cómo la vinculina regula las interacciones proteína-proteína en las uniones celulares.
Principales métodos:
- Cristalografía de rayos X de la vinculina de cuerpo entero (1.066 aminoácidos).
- Análisis de las interacciones del dominio proteico y los cambios conformacionales.
- Estudios de vinculación termodinámica y estructural de los dominios de la vinculina.
Principales resultados:
- La estructura cristalina revela una conformación autoinhibida de cinco dominios.
- El dominio de la cabeza de la vinculina en forma de pinza contiene el dominio de la cola carboxiterminal.
- La unión de ligandos está regulada estérico y alostéricamente; los cambios de conformación de dominio están vinculados.
Conclusiones:
- Una vía de activación combinatoria asegura que la vinculina se active sólo en los sitios de adhesión.
- La activación de la vinculina requiere la unión simultánea de múltiples socios en las uniones celulares.
- Las ideas estructurales explican el papel de la vinculina en la vinculación de la F-actina a las moléculas de la caderina y la integrina.
Más Videos Relacionados
Videos de Conceptos Relacionados
01:24Overview of Cell-Matrix Interactions
The extracellular matrix or ECM holds cells together to form a tissue and allows the cells within the tissue to communicate. ECM comprises proteins such as fibronectin, collagen, laminin, etc. The most abundant protein in this space is collagen. Collagen fibers are interwoven with carbohydrate-containing protein molecules called proteoglycans. ECM allows cell migration and provides a structural scaffold at cell adhesion that anchors the cell when the extracellular matrix proteins interact with...
01:15Activation of Integrins
Integrins bind ligands and transmit information from outside the cell to inside or vice-versa through an "outside-in signaling" or "inside-out signaling."
In "outside-in signaling," external factors in the extracellular space bind to exposed ligand binding sites on integrins. This causes the inactive protein to undergo a conformational change to become active. Integrins are often clustered on the cell membrane. Repetitive and regularly spaced ligand binding events provide an effective stimulus.
In "outside-in signaling," external factors in the extracellular space bind to exposed ligand binding sites on integrins. This causes the inactive protein to undergo a conformational change to become active. Integrins are often clustered on the cell membrane. Repetitive and regularly spaced ligand binding events provide an effective stimulus.
01:17Intracellular Signaling Affects Focal Adhesions
Integrins act both as extracellular input receivers and as intracellular processing activators. As their name suggests, integrins are entirely integrated into the membrane structure. Their hydrophobic membrane-spanning regions interact with the phospholipid bilayer's hydrophobic region. These membrane receptors provide extracellular attachment sites for effectors like hormones and growth factors. They activate intracellular response cascades when their effectors are bound and active.
Some...
Some...
01:03Anchoring Junctions
Anchoring junctions are multiprotein complexes that help cells connect to other cells and the extracellular matrix. Anchoring junctions are present on the lateral and basal surfaces of cells, providing strong and flexible connections. Focal adhesions are often formed due to cell interactions with the ECM substrata, which initiate signal transduction via kinase cascades and other mechanisms. Together, they provide stability and tissue integrity. There are three types of anchoring junctions:...
01:13Cell-matrix's Response to Mechanical Forces
In animal cells, the extracellular matrix allows cells within tissues to withstand external stresses and transmits signals from the outside of the cell to the inside. The extracellular matrix is extensive, and its composition varies between different types of tissues. For example, the reticular fibers and ground substance make up the ECM in loose connective tissue, while collagen and bone minerals make up the ECM of bone tissue.
Anchoring junctions mechanically attach a cell to the...
Anchoring junctions mechanically attach a cell to the...
01:26Tension Response at Adherens Junctions
The adherens junctions that anchor cells together are multi-protein complexes that dynamically adapt to mechanical stimuli such as tensile forces and shear stress. Mechanosensory proteins in these junctions can sense such mechanical stimuli and undergo a shift in their conformation, resulting in an altered function — a process called mechanotransduction.
α-Catenin as a Mechanosensory Protein
The α-catenin of adherens junctions is an allosteric protein with three VH (vinculin homology) domains...
α-Catenin as a Mechanosensory Protein
The α-catenin of adherens junctions is an allosteric protein with three VH (vinculin homology) domains...