Video Experimental Relacionado

Updated: Feb 20, 2026

Examining BCL-2 Family Function with Large Unilamellar Vesicles

Examining BCL-2 Family Function with Large Unilamellar Vesicles

Published on: October 5, 2012

Evitar la apoptosis mitocondrial mediante la oligomerización de Bax impulsada por Bcl-2 en superficies de membrana

Sophie E Ayscough^1,2,3, Luke A Clifton¹, Jörgen Ådén⁴

¹ISIS Pulsed Neutron and Muon Source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Science & Innovation Campus, Didcot, Oxfordshire OX11 OQX, U.K.

ACS chemical biology

|February 18, 2026

Resumen

La proteína antiapoptótica Bcl-2 neutraliza la proteína proapoptótica Bax formando complejos, previniendo la muerte celular. Este mecanismo, observado incluso con lípidos promotores, puede explicar cómo las células cancerosas evaden la apoptosis.

Área de la Ciencia:

Biofísica
Biología Molecular
Investigación del Cáncer

Sus antecedentes:

La familia de proteínas Bcl-2 regula la apoptosis controlando la permeabilización de la membrana externa mitocondrial.
La apoptosis disfuncional es un sello distintivo de muchos cánceres, lo que convierte su regulación en un área clave de investigación.
Se implican interacciones directas entre Bax y Bcl-2 en la apoptosis, pero los mecanismos moleculares siguen sin estar claros.

Objetivo del estudio:

Elucidar las interacciones moleculares entre Bax y Bcl-2 en la membrana mitocondrial.
Comprender los principios biofísicos que rigen la regulación de la apoptosis por estas proteínas.
Investigar cómo Bcl-2 neutraliza la permeabilización de la membrana externa mitocondrial mediada por Bax.

Principales métodos:

Estudio biofísico sistemático utilizando reflectometría de neutrones (NR) y ATR-FTIR.
Análisis de cambios espaciales y temporales en superficies modelo de la membrana externa mitocondrial.
Análisis cinético de interacciones proteína-proteína.

Principales resultados:

Bcl-2 secuestra Bax a través de la heterodimerización con Bax y la oligomerización de Bax.
Se identificó un proceso cinético de dos pasos: formación rápida de heterodímeros Bcl-2/Bax seguida de una oligomerización más lenta de Bax.
Este mecanismo de secuestro persiste en presencia de cardiolipina, que normalmente promueve la formación de poros de Bax.

Conclusiones:

Bcl-2 neutraliza Bax a través del atrapamiento estructural, previniendo la apoptosis.
Este mecanismo proporciona información sobre cómo las células cancerosas evaden la apoptosis, incluso con niveles elevados de Bax.
Comprender esta interacción es crucial para desarrollar nuevas terapias contra el cáncer dirigidas a la evasión de la apoptosis.

Palabras clave:

biofísica biología molecular investigación del cáncer apoptosis proteína Bcl-2 proteína Bax membrana mitocondrial terapia contra el cáncer

Más Videos Relacionados

Isolation and Functional Analysis of Mitochondria from Cultured Cells and Mouse Tissue

Isolation and Functional Analysis of Mitochondria from Cultured Cells and Mouse Tissue

Published on: March 23, 2015

F1FO ATPase Vesicle Preparation and Technique for Performing Patch Clamp Recordings of Submitochondrial Vesicle Membranes

F1FO ATPase Vesicle Preparation and Technique for Performing Patch Clamp Recordings of Submitochondrial Vesicle Membranes

Published on: May 4, 2013

Videos de Conceptos Relacionados

The Intrinsic Apoptotic Pathway

The Intrinsic Apoptotic Pathway

Internal cellular stress, such as cellular injury or hypoxia, triggers intrinsic apoptosis. The B-cell lymphoma 2 (Bcl-2) family of proteins are the primary regulators of the intrinsic apoptotic pathway. For example, during DNA damage, checkpoint proteins, such as Ataxia Telangiectasia Mutated (ATM protein) and Checkpoints Factor-2 (Chk2) proteins, are activated. These proteins phosphorylate p53 which further activates pro-apoptotic proteins, such as Bax, Bak, PUMA, and Noxa, and inhibits...

Translocation of Proteins into the Mitochondria

Translocation of Proteins into the Mitochondria

Mitochondrial precursors are translocated to the internal subcompartments via independent mechanisms involving distinct protein machineries called translocases.
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...

Apoptosis

Apoptosis

Apoptosis is a combination of two Greek words, 'apo' and 'ptosis,' meaning separation and falling off, respectively. Hippocrates used this word to describe gangrene, which was caused due to bandaging of fractured bones. Apoptosis was distinguished from necrosis in 1970 when John Kerr reported observations of morphological changes occurring during apoptosis. During one experiment, he observed that the disruption of blood supply to the liver tissue resulted in a size...

Mitochondrial Precursor Proteins

Mitochondrial Precursor Proteins

Mitochondrial precursors are partially unfolded or loosely folded polypeptide chains. Newly synthesized precursors are inhibited from spontaneously folding into their native conformation by the cytosolic chaperones, heat shock proteins 70 (Hsp70), and mitochondrial import stimulation factors (MSFs). Precursors bound to MSFs are guided to the TOM70-TOM37 receptors, while precursors bound to Hsp70 chaperones are targetted to TOM20-TOM22 receptor complexes.
Most of the mitochondrial...

The Extrinsic Apoptotic Pathway

The Extrinsic Apoptotic Pathway

The extrinsic apoptotic pathway is initiated when extracellular death-inducing signals, such as specific cytokines, activate the death receptors expressed on the cell surface. The immune cells involved in this pathway are natural killer cells (NK cells) and cytotoxic T-lymphocytes. NK cells are critical in innate immune response, while cytotoxic T-lymphocytes are associated with adaptive immune response. These cells recognize specific receptors expressed on the altered cells and activate...

Mitochondrial Membranes

Mitochondrial Membranes

A single mitochondrion is a bean-shaped organelle enclosed by a double-membrane system. The outer membrane of mitochondria is smooth and contains many porins - the integral membrane transporters. Porins enable free diffusion of ions and small uncharged molecules through the outer mitochondrial membrane but limit the transport of molecules larger than 5000 Daltons. Further, the outer mitochondrial membrane forms a unique structure called membrane contact sites with other subcellular organelles,...