Video Experimental Relacionado
Updated: Aug 14, 2026
10:16
Promoter Capture Hi-C: High-resolution, Genome-wide Profiling of Promoter Interactions
Published on: June 28, 2018
El complejo de cofactores de transcripción CRSP es necesario para la actividad de la proteína Sp1 de unión al
1Howard Hughes Medical Institute, University of California at Berkeley, Molecular and Cell Biology, 94720-3204, USA.
Nature
|February 16, 1999
Resumen
Los investigadores descubrieron un nuevo complejo de coactivador humano, CRSP, esencial para la transcripción génica. CRSP trabaja con TFIID para activar la transcripción por Sp1, revelando un mecanismo combinatorio para el ensamblaje del coactivador.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Regulación genética Reglamento genético.
- La bioquímica es la bioquímica.
Sus antecedentes:
- La activación de la transcripción génica en metazoos es un proceso complejo de varios pasos.
- Los factores de unión del potenciador transcripcional, como Sp1, requieren coactivadores, incluidas las subunidades TFIID, para su activación.
- La identidad de los cofactores adicionales necesarios para la transcripción mediada por Sp1 ha permanecido elusiva.
Objetivo del estudio:
- Identificar y caracterizar nuevos cofactores involucrados en la activación transcripcional mediada por Sp1.
- Para aclarar la composición y función del recién descubierto complejo de cofactores, CRSP.
Principales métodos:
- Purificación del complejo CRSP.
- Identificación de subunidades a través de la caracterización del complejo proteico.
- La clonación de genes y el análisis de secuencias de las subunidades del CRSP.
- Estudios de inmunodepleción para evaluar la función del cofactor.
Principales resultados:
- Un nuevo complejo de cofactor humano, CRSP (aprox. 700K M(r)), compuesto por nueve subunidades, fue identificado.
- CRSP es esencial para la activación transcripcional por Sp1, que funciona junto con TAF{II) s.
- Las subunidades de CRSP muestran homología con el mediador de levadura y los factores de alargamiento, incluidos Med7, Rgr1 y TFIIS.
- CRSP p200 es idéntico a la subunidad TRIP2/PBP del coactivador del receptor de hormonas nucleares.
Conclusiones:
- La CRSP es un coactivador crucial requerido para la transcripción génica mediada por Sp1.
- La composición de la subunidad de CRSP sugiere dominios funcionales conservados en todas las especies.
- Los hallazgos indican un mecanismo de ensamblaje combinatorio para complejos de coactivadores en la activación transcripcional.
Más Videos Relacionados
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...
02:16Transcription 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...
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...