Video Experimental Relacionado
Updated: Jul 6, 2026
13:51
The MultiBac Protein Complex Production Platform at the EMBL
Published on: July 11, 2013
Carga del factor de transcripción en el promotor MMTV: un mecanismo bimodal para la activación del promotor
T K Archer1, P Lefebvre, R G Wolford
1Hormone Action and Oncogenesis Section, Laboratory of Molecular Virology, National Cancer Institute, Bethesda, MD 20892.
Science (New York, N.Y.)
|March 20, 1992
Resumen
Las hormonas glucocorticoides remodelan la cromatina en el promotor del virus del tumor mamario del ratón, lo que permite la unión del factor de transcripción NF1 / CTF. Este proceso dependiente de las hormonas controla la inducción génica mediante la regulación del acceso al ADN promotor.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- La epigenética es la epigenética.
- Regulación genética Reglamento genético.
Sus antecedentes:
- La estructura de cromatina del promotor del virus del tumor mamario del ratón (MMTV) influye en la accesibilidad del factor de transcripción.
- Comprender cómo se regula dinámicamente la arquitectura del promotor es crucial para descifrar el control de la expresión génica.
Objetivo del estudio:
- Para investigar el papel de la remodelación de la cromatina en la transcripción dependiente de las hormonas del promotor MMTV.
- Para aclarar el mecanismo de reclutamiento del factor nuclear 1/CCAAT del factor de transcripción (NF1/CTF) al promotor de MMTV.
Principales métodos:
- Análisis de la fase de los nucleosomas promotores de MMTV en las células de roedores.
- Evaluación de la accesibilidad de los agentes nucleolíticos y de unión NF1/CTF antes y después del tratamiento con glucocorticoides.
- Comparación del comportamiento del promotor introducido transitoriamente frente al comportamiento del promotor integrado.
Principales resultados:
- El promotor de MMTV adopta una matriz de nucleosomas por fases en contextos integrados, excluyendo NF1/CTF.
- El tratamiento con glucocorticoides induce la remodelación de la cromatina, permitiendo la unión NF1/CTF y el acceso nucleolítico.
- Los promotores introducidos transitoriamente muestran unión constitutiva NF1/CTF y ataque nucleolítico independiente de las hormonas.
Conclusiones:
- La inducción del promotor MMTV es un proceso bimodal que implica la remodelación de la cromatina dependiente de las hormonas.
- Los cambios en la cromatina mediados por receptores facilitan la carga de NF1/CTF y el reclutamiento de otros factores de transcripción.
Videos de Conceptos Relacionados
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...
02:33Initiation of Translation
Initiating translation is complex because it involves multiple molecules. Initiator tRNA, ribosomal subunits, and eukaryotic initiation factors (eIFs) are all required to assemble on the initiation codon of mRNA. This process consists of several steps that are mediated by different eIFs.
First, the initiator tRNA must be selected from the pool of elongator tRNAs by eukaryotic initiation factor 2 (eIF2). The initiator tRNA (Met-tRNAi) has conserved sequence elements including modified bases at...
First, the initiator tRNA must be selected from the pool of elongator tRNAs by eukaryotic initiation factor 2 (eIF2). The initiator tRNA (Met-tRNAi) has conserved sequence elements including modified bases at...
02:23Master Transcription Regulators
Master transcription regulators are regulatory proteins that are predominantly responsible for regulating the expression of multiple genes. Often these genes work in concert to drive a complex process. Activation of a master transcription regulator can lead to a cascade of transcriptional activation necessary for that outcome. These regulators can directly bind to the regulatory sequences of the various genes involved, or they can indirectly regulate transcription by binding to regulatory...
02:23Master Transcription Regulators
Master transcription regulators are regulatory proteins that are predominantly responsible for regulating the expression of multiple genes. Often these genes work in concert to drive a complex process. Activation of a master transcription regulator can lead to a cascade of transcriptional activation necessary for that outcome. These regulators can directly bind to the regulatory sequences of the various genes involved, or they can indirectly regulate transcription by binding to regulatory...
01:16Calmodulin-dependent Signaling
Calmodulin (CaM) is a calcium-binding protein in eukaryotes that controls various calcium-regulated cellular processes. It has four calcium-binding sites that bind calcium to form the calcium-calmodulin ( Ca2+-CaM) complex. GPCR stimulation increases the calcium levels in the cells that bind to CaM and induces a conformational change.
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
01:27Transducer Mechanism: Enzyme-Linked Receptors
Enzyme-linked receptors are cell-surface receptors acting as an enzyme or associating with an enzyme intracellularly. They make excellent drug targets. Drugs can bind to the extracellular ligand-binding domain or directly affect their enzymatic domain and alter their activity.
Major types that are helpful drug targets include:
Major types that are helpful drug targets include: