Video Experimental Relacionado
Updated: Jul 29, 2026
07:29
Determination of Molecular Structures of HIV Envelope Glycoproteins using Cryo-Electron Tomography and Automated Sub-tomogram Averaging
Published on: December 1, 2011
Estructura atómica del ectodominio del VIH-1 gp41
W Weissenhorn1, A Dessen, S C Harrison
1Laboratory of Molecular Medicine, The Children's Hospital, Boston, Massachusetts 02215, USA.
Nature
|May 22, 1997
Resumen
El análisis estructural del ectodominio HIV-1 gp41 revela un núcleo de bobina en espiral alfa-hélico de triple cadena. Esta estructura, determinada por cristalografía de rayos X, sugiere un mecanismo común de fusión de la membrana viral.
Área de la Ciencia:
- Biología Estructural Biología estructural.
- Virología Virología.
- Biología Molecular Biología Molecular
Sus antecedentes:
- La entrada del virus de la inmunodeficiencia humana tipo 1 (VIH-1) en las células huésped está mediada por el complejo glicoproteínico del sobre gp120/gp41.
- El complejo gp120/gp41 sufre cambios conformacionales al unirse a CD4 y co-receptores, iniciando la fusión de la membrana.
Objetivo del estudio:
- Para determinar la estructura tridimensional de un fragmento resistente a la proteasa del ectodominio del VIH-1 gp41.
- Para aclarar la base estructural de la fusión de la membrana viral.
Principales métodos:
- Se empleó cristalografía de rayos X para determinar la estructura del ectodominio gp41.
- El ectodominio gp41 fue solubilizado utilizando una bobina trímera GCN4 enrollada en lugar del péptido de fusión.
Principales resultados:
- La estructura central del fragmento de ectodominio gp41 es una bobina en espiral alfa helicoidal de triple cadena extendida.
- El extremo amino se encuentra en la punta de la bobina enrollada.
- Una hélice alfa carboxiterminal se empaca en sentido inverso contra la bobina enrollada, uniendo los terminales.
Conclusiones:
- La estructura determinada proporciona información sobre el mecanismo de la fusión de la membrana del VIH-1.
- Las similitudes estructurales con otras proteínas de fusión viral sugieren un mecanismo de iniciación de fusión conservado en diferentes virus.
Videos de Conceptos Relacionados
00:56Viral Structure
Viruses are extraordinarily diverse in shape and size, but they all have several structural features in common. All viruses have a core that contains a DNA- or RNA-based genome. The core is surrounded by a protective coat of proteins called the capsid. The capsid is composed of subunits called capsomeres. The capsid and genome-containing core are together known as the nucleocapsid.
01:10Antibody Structure
Overview
Antibodies, also known as immunoglobulins (Ig), are essential players of the adaptive immune system. These antigen-binding proteins are produced by B cells and make up 20 percent of the total blood plasma by weight. In mammals, antibodies fall into five different classes, which each elicits a different biological response upon antigen binding.
The Y-Shaped Structure of Antibodies Consists of Four Polypeptide Chains
Antibodies consist of four polypeptide chains: two identical heavy...
Antibodies, also known as immunoglobulins (Ig), are essential players of the adaptive immune system. These antigen-binding proteins are produced by B cells and make up 20 percent of the total blood plasma by weight. In mammals, antibodies fall into five different classes, which each elicits a different biological response upon antigen binding.
The Y-Shaped Structure of Antibodies Consists of Four Polypeptide Chains
Antibodies consist of four polypeptide chains: two identical heavy...
02:15Protein and Protein Structure
Proteins are one of the most abundant organic molecules in living systems and have the most diverse range of functions of all macromolecules. Proteins may be structural, regulatory, contractile, or protective. They may serve in transport, storage, or membranes; or they may be toxins or enzymes. Their structures, like their functions, vary greatly. They are all, however, amino acid polymers arranged in a linear sequence.
A protein's shape is critical to its function. For example, an enzyme can...
A protein's shape is critical to its function. For example, an enzyme can...
02:26Conservation of Protein Domains Over Different Proteins
Protein domains are small structurally independent units that are part of a single amino acid chain. Although these domains are often structurally independent, they may rely on synergistic effects to perform their functions as part of a larger protein. Protein domains may be conserved within the same organism, as well as across different organisms.
A limited set of protein domains often duplicate and recombine during evolution. These domains can be organized in different combinations to form...
A limited set of protein domains often duplicate and recombine during evolution. These domains can be organized in different combinations to form...
01:10Antibody Structure
Overview
Antibodies, also known as immunoglobulins (Ig), are essential players of the adaptive immune system. These antigen-binding proteins are produced by B cells and make up 20 percent of the total blood plasma by weight. In mammals, antibodies fall into five different classes, which each elicits a different biological response upon antigen binding.
The Y-Shaped Structure of Antibodies Consists of Four Polypeptide Chains
Antibodies consist of four polypeptide chains: two identical heavy...
Antibodies, also known as immunoglobulins (Ig), are essential players of the adaptive immune system. These antigen-binding proteins are produced by B cells and make up 20 percent of the total blood plasma by weight. In mammals, antibodies fall into five different classes, which each elicits a different biological response upon antigen binding.
The Y-Shaped Structure of Antibodies Consists of Four Polypeptide Chains
Antibodies consist of four polypeptide chains: two identical heavy...
01:19Inhibitors of Virion Maturation and Assembly
As part of their replication cycle, certain viruses synthesize long precursor proteins called polyproteins within infected host cells. In human immunodeficiency virus (HIV), two major polyproteins are produced: Gag and Gag-Pol. The Gag polyprotein supplies the structural components of the virus, while Gag-Pol includes essential viral enzymes such as reverse transcriptase, integrase, and protease. After synthesis, these polyproteins move to the host cell membrane, where they assemble into an...