Video Experimental Relacionado
Updated: Sep 23, 2025
11:34
High-throughput Screening for Broad-spectrum Chemical Inhibitors of RNA Viruses
Published on: May 5, 2014
14.0K
Interrumpir los circuitos de autorrepresión genera "letalidad en bucle abierto" para producir agentes antivirales
Sonali Chaturvedi1, Michael Pablo1, Marie Wolf1
1Gladstone/UCSF Center for Cell Circuitry, Gladstone Institutes, San Francisco, CA 94158, USA; Gladstone Institute of Virology, Gladstone Institutes, San Francisco, CA 94158, USA.
Cell
|May 13, 2022
Resumen
La interrupción de la retroalimentación negativa en las redes de genes con señuelos de ácido nucleico causa "letalidad de circuito abierto" viral, inhibiendo la replicación. Esta nueva estrategia antimicrobiana muestra altas barreras de resistencia contra virus como los herpesvirus y el SARS-CoV-2.
Área de la Ciencia:
- Biología molecular
- Virología
- La genética
Sus antecedentes:
- Las redes reguladoras de genes utilizan la autorrepresión (retroalimentación negativa) para la homeostasis y para prevenir la expresión génica aberrante.
- La replicación viral se basa en redes complejas de regulación génica que pueden ser objeto de intervención terapéutica.
Objetivo del estudio:
- Investigar si la interrupción de la retroalimentación negativa de la transcripción en los virus puede inhibir la replicación y establecer una barrera alta para la resistencia.
- Para demostrar una nueva estrategia terapéutica llamada "letalidad de bucle abierto" rompiendo la homeostasis viral.
Principales métodos:
- Utilizó señuelos de ácido nucleico que imitaban los sitios cis-reguladores para interrumpir los circuitos de retroalimentación negativa en la expresión génica viral.
- Se evaluó la replicación viral, la citotoxicidad, la sinergia con los antivirales existentes y la evolución de la resistencia en los virus del herpes y los modelos de SARS-CoV-2.
- Evaluación de la eficacia terapéutica en un modelo de infección por herpesvirus en ratones.
Principales resultados:
- Los disruptores de retroalimentación redujeron la replicación del virus del herpes en más de 2 logs, con valores subnanomolares de IC50, sin activar la inmunidad innata.
- Este enfoque sinergizó con los antivirales estándar y mostró eficacia in vivo, sin que surgieran mutantes de resistencia en cultivos a largo plazo.
- La interrupción de un circuito de retroalimentación del SARS-CoV-2 también indujo la letalidad en bucle abierto, reduciendo los títulos virales en más de 1 log.
Conclusiones:
- Interrumpir la retroalimentación negativa para generar "letalidad en bucle abierto" es una estrategia viable para la terapia antiviral.
- Este enfoque ofrece una alta barrera genética para la resistencia, en contraste con las limitaciones antivirales actuales.
- Los señuelos de ácido nucleico representan una nueva clase prometedora de antimicrobianos dirigidos a la regulación genética viral.
Videos de Conceptos Relacionados
01:29Viruses with RNA Genomes
169
RNA viruses are categorized into positive-strand, negative-strand, or double-stranded groups based on their genomic structure and replication mechanisms. This classification dictates how they exploit host cellular machinery for protein synthesis and replication. Some RNA viruses also utilize reverse transcription as part of their life cycle, further diversifying their replication strategies.Positive-Strand RNA VirusesPositive-strand RNA viruses have genomes that function directly as messenger...
169
01:10Retrovirus Life Cycles
47.1K
Retroviruses have a single-stranded RNA genome that undergoes a special form of replication. Once the retrovirus has entered the host cell, an enzyme called reverse transcriptase synthesizes double-stranded DNA from the retroviral RNA genome. This DNA copy of the genome is then integrated into the host’s genome inside the nucleus via an enzyme called integrase. Consequently, the retroviral genome is transcribed into RNA whenever the host’s genome is transcribed, allowing the...
47.1K
01:26Size and Structure of Viral Genomes
180
Viral genomes exhibit remarkable diversity in size, structure, and composition, influencing their replication strategies and interactions with host cells. These genomes consist of either DNA or RNA and may be linear or circular. Additionally, they can be single-stranded or double-stranded, with each configuration affecting how the virus propagates within a host. RNA viruses, for instance, generally have smaller genomes than DNA viruses, a factor that contributes to their high mutation rates and...
180
00:36Viral Mutations
33.6K
A mutation is a change in the sequence of bases of DNA or RNA in a genome. Some mutations occur during replication of the genome due to errors made by the polymerase enzymes that replicate DNA or RNA. Unlike DNA polymerase, RNA polymerase is prone to errors because it is not capable of “proofreading” its work. Viruses with RNA-based genomes, like HIV, therefore accrue mutations faster than viruses with DNA-based genomes. Because mutation and recombination provide the raw material...
33.6K
01:29Subviral Agents
144
Subviral agents are infectious entities that resemble viruses but lack one or more viral components, such as a capsid or essential replication machinery. These agents include viroids, prions, and satellites, each possessing distinct structural and functional characteristics that influence their mode of infection and replication.Viroids are the simplest subviral agents, consisting of circular, single-stranded RNA molecules without a protein coat. They exclusively infect plants, relying entirely...
144
02:33Retroviruses
12.7K
Retroviruses and retrotransposons both insert copies of their genetic elements into the genome of the host cell. Thus, the viral genes are passed on when the host genome is replicated or translated. A typical retroviral DNA sequence contains 3-4 genes that encode the different proteins required for its structural assembly and function as a molecular parasite. This DNA is transcribed into a single mRNA, which is very similar in structure to conventional mRNAs, i.e., it is capped at the 5’...
12.7K