Video Experimental Relacionado
Updated: Jul 6, 2026
07:44
High-throughput Purification of Affinity-tagged Recombinant Proteins
Published on: August 26, 2012
El factor de transcripción IIB se acetila a sí mismo para regular la transcripción
Chu H Choi1, Makoto Hiromura, Anny Usheva
1Endocrinology Division, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 99 Brookline Avenue, Boston, Massachusetts 02215, USA.
Nature
|August 22, 2003
Resumen
El factor de transcripción general TFIIB se somete a la acetilación, una modificación posterior a la traducción. Esta autoacetilación estabiliza las interacciones y activa la transcripción basal, vinculando el acetil-CoA a la regulación génica.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Regulación genética Reglamento genético.
- La bioquímica es la bioquímica.
Sus antecedentes:
- La acetilación es una modificación post-traducional reguladora conocida.
- El papel de la acetilación en la regulación de los factores basales de transcripción sigue siendo en gran parte inexplorado.
- Los factores generales de transcripción son cruciales para iniciar la transcripción eucariota.
Objetivo del estudio:
- Investigar el papel de la acetilación en la regulación de los factores basales de transcripción.
- Para determinar si el TFIIB (factor de transcripción general II B) está sujeto a la acetilación.
- Para aclarar las consecuencias funcionales de la acetilación del TFIIB.
Principales métodos:
- Análisis bioquímicos para detectar y caracterizar la acetilación de TFIIB.
- Ensayos de transcripción in vitro con TFIIB. recombinante y celular.
- Mutagénesis dirigida al sitio para crear mutantes no acetilables del TFIIB (K238A).
- Análisis de las interacciones TFIIB-TFIIF.
Principales resultados:
- TFIIB es acetilado en un residuo específico de lisina (K238).
- TFIIB posee la actividad de la autoacetiltransferasa, utilizando el acetil-CoA.
- La acetilación estabiliza la interacción entre el TFIIB y el TFIIF.
- La autoacetilación de TFIIB mejora la iniciación de la transcripción basal tanto in vitro como en las células.
- Un mutante K238A no acetilable de TFIIB no puede activar la transcripción.
Conclusiones:
- La acetilación TFIIB es un nuevo mecanismo de regulación para la transcripción basal.
- El TFIIB actúa como una autoacetiltransferasa, vinculando el acetil-CoA a la transcripción.
- La acetilación de TFIIB juega un papel crítico en la estabilización de las interacciones de los factores de transcripción y la promoción de la expresión génica.
Videos de Conceptos Relacionados
02:16Transcription Factors
Tissue-specific transcription factors contribute to diverse cellular functions in mammals. For example, the gene for beta globin, a major component of hemoglobin, is present in all cells of the body. However, it is only expressed in red blood cells because the transcription factors that can bind to the promoter sequences of the beta globin gene are only expressed in these cells. Tissue-specific transcription factors also ensure that mutations in these factors may impair only the function of...
02:36RNA Polymerase II Accessory Proteins
Proteins that regulate transcription can do so either via direct contact with RNA Polymerase or through indirect interactions facilitated by adaptors, mediators, histone-modifying proteins, and nucleosome remodelers. Direct interactions to activate transcription is seen in bacteria as well as in some eukaryotic genes. In these cases, upstream activation sequences are adjacent to the promoters, and the activator proteins interact directly with the transcriptional machinery. For example, in...
02:04Co-activators and Co-repressors
Gene transcription is regulated by the synergistic action of several proteins that form a complex at a gene regulatory site. This is observed in eukaryotes, where the regulation of gene expression is a complex process. Regulatory proteins in eukaryotes can broadly be classified into two types – regulators that bind directly to specific DNA sequences and co-regulators that associate with regulatory proteins but cannot directly bind to the DNA. These co-regulators are further divided into...
01:30General Transcription Factors
Tissue-specific transcription factors contribute to diverse cellular functions in mammals. For example, the gene for beta globin, a major component of hemoglobin, is present in all cells of the body. However, it is only expressed in red blood cells because the transcription factors that can bind to the promoter sequences of the beta globin gene are only expressed in these cells. Tissue-specific transcription factors also ensure that mutations in these factors may impair only the function of...
02:36RNA Polymerase II Accessory Proteins
Proteins that regulate transcription can do so either via direct contact with RNA Polymerase or through indirect interactions facilitated by adaptors, mediators, histone-modifying proteins, and nucleosome remodelers. Direct interactions to activate transcription is seen in bacteria as well as in some eukaryotic genes. In these cases, upstream activation sequences are adjacent to the promoters, and the activator proteins interact directly with the transcriptional machinery. For example, in...
02:04Co-activators and Co-repressors
Gene transcription is regulated by the synergistic action of several proteins that form a complex at a gene regulatory site. This is observed in eukaryotes, where the regulation of gene expression is a complex process. Regulatory proteins in eukaryotes can broadly be classified into two types – regulators that bind directly to specific DNA sequences and co-regulators that associate with regulatory proteins but cannot directly bind to the DNA. These co-regulators are further divided into...