JoVE - Journal of Visualized Experiments
JoVE Visualize
Contact Us
Esta página ha sido traducida por una máquina. Otras páginas pueden seguir apareciendo en inglés. View in English

Generación de fuerza dependiente de ATP y escisión de la membrana por ESCRT-III y Vps4

  • 0Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA.
Clinical Neuroscience (new York, N.y.) +

|

22 de diciembre de 2018

|

22 de diciembre de 2018

Ver abstracta en PubMed

Resumen

Este resumen es generado por máquina.

Los complejos de clasificación endosómica (ESCRT) impulsan la escisión de la membrana. Este estudio muestra que los conjuntos ESCRT-III y Vps4 alimentados por ATP generan fuerza para cortar membranas, verificando predicciones biológicas clave.

Área De La Ciencia

  • Biología celular
  • La bioquímica
  • Los motores moleculares

Sus Antecedentes

  • Los complejos de clasificación endosómica requeridos para el transporte (ESCRT) son cruciales para la remodelación de la membrana.
  • La maquinaria ESCRT media la escisión de la membrana en diversos procesos celulares como el brote viral y la citoquinesis.

Objetivo Del Estudio

  • Investigar el mecanismo de escisión de la membrana por el ESCRT-III y el Vps4.
  • Visualizar y verificar directamente las fuerzas generadas durante la escisión mediada por la ESCRT.

Principales Métodos

  • Reconstitución de las subunidades ESCRT-III (Snf7, Vps24, Vps2) y Vps4 en las vesículas gigantes.
  • Creación de nanotubos de membrana para la observación de la dinámica de escisión.
  • Foto-desenvejecimiento de ATP para desencadenar la generación y la escisión de la fuerza mediada por el ESCRT.

Principales Resultados

  • La generación de fuerza dependiente del ATP dentro de los nanotubos condujo a la escisión de la membrana.
  • La actividad catalítica de Vps4 y su acoplamiento a ESCRT-III fueron esenciales para la escisión.
  • Las imágenes revelaron puntos Snf7 y Vps4 correlacionados con fuerza, constricción y escisión previa.

Conclusiones

  • Demuestra directamente que los conjuntos de hidrólisis de ATP de ESCRT-III y Vps4 cortan las membranas.
  • Verifica el modelo de larga data de escisión de la membrana mediada por el ESCRT a través de la generación de fuerza.

Videos de Conceptos Relacionados

ATP Yield 01:31

78.9K

Cellular respiration produces 30 - 32 ATP per glucose molecule. Although most of the ATP results from oxidative phosphorylation and the electron transport chain (ETC), 4 ATP are gained beforehand (2 from glycolysis and 2 from the citric acid cycle).
The ETC is embedded in the inner mitochondrial membrane and is comprised of four main protein complexes and an ATP synthase. NADH and FADH2 pass electrons to these complexes, which pump protons into the intermembrane space. This distribution of...

ATP Driven Pumps III: V-type Pumps 01:30

4.8K

V-type pumps are ATP-driven pumps found in the vacuolar membranes of plants, yeast, endosomal and lysosomal membranes of animal cells, plasma membranes of a few specialized eukaryotic cells, and some prokaryotes. They are also known as the V1Vo-ATPase, that couple ATP hydrolysis to transport protons against a concentration gradient.
The peripheral or cytosolic V1 domain with eight subunits is involved in ATP hydrolysis. The integral or transmembrane V0 domain containing at least five subunits...

Hydrolysis of ATP 01:08

81.3K

The bonds of adenosine triphosphate (ATP) can be broken through the addition of water, releasing one or two phosphate groups in an exergonic process called hydrolysis. This reaction liberates the energy in the bonds for use in the cell—for instance, to synthesize proteins from amino acids.
If one phosphate group is removed, a molecule of ADP—adenosine diphosphate—remains, along with inorganic phosphate. ADP can be further hydrolyzed to AMP—adenosine...

Electromotive Force 02:36

30.2K

Electricity is generated by either electrons or ions flowing through a solution or a conducting medium. This flow of electrons or specifically electrical charge is defined as an electric current. When electrons move through a wire, they generate an electric current. It can be recalled  that in a redox reaction, electrons are lost and gained. In the spontaneous redox reaction of zinc  with copper, when zinc is immersed in a copper ion solution, a transfer of electrons from one substance to...

Contact-dependent Signaling 01:19

47.0K

Contact-dependent signaling, as the name suggests, requires that communicating cells be in direct contact with each other. This is achieved either through receptor-ligand interactions or by specialized cytoplasmic channels that allow the flow of small molecules between cells. In animal cells, channels called gap junctions facilitate contact-dependent signaling in certain tissues, whereas, plasmodesmata perform a similar function in plants.
Gap Junctions
In animal cells, gap junctions are formed...

Intermolecular Forces 03:13

71.0K

Atoms and molecules interact through bonds (or forces): intramolecular and intermolecular. The forces are electrostatic as they arise from interactions (attractive or repulsive) between charged species (permanent, partial, or temporary charges) and exist with varying strengths between ions, polar, nonpolar, and neutral molecules. The different types of intermolecular forces are ion–dipole, dipole–dipole, hydrogen bonds, and dispersion; among these, dipole–dipole, hydrogen...