Video Experimental Relacionado
Updated: May 20, 2026
07:44
High-throughput Purification of Affinity-tagged Recombinant Proteins
Published on: August 26, 2012
La cooperación en la transactivación entre el receptor de ácido retinoico y el TFIID requiere una actividad análoga a
A Berkenstam1, M M Vivanco Ruiz, D Barettino
1EMBL, Gene Expression Program, Heidelberg, Germany.
Cell
|May 1, 1992
Resumen
El ácido retinoico (RA) activa la transcripción del promotor RAR beta 2 en las células de carcinoma embrionario. Este proceso implica una cooperación funcional entre el receptor RA (RAR) y el TFIID humano, mediada por una actividad similar a la E1A.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Regulación genética Reglamento genético.
- La diferenciación celular es la diferenciación celular.
Sus antecedentes:
- El ácido retinoico (AR) es crucial para la diferenciación celular.
- Las células de carcinoma embrionario (CE) son un modelo para el desarrollo temprano.
- El promotor del receptor del ácido retinoico beta 2 (RAR beta 2) es activado por la AR en las células EC.
Objetivo del estudio:
- Investigar los mecanismos moleculares de la transcripción inducida por AR del promotor RAR beta 2 en las células EC.
- Para aclarar el papel de la proteína de unión a la caja TATA (TFIID) y el receptor de AR (RAR) en este proceso.
Principales métodos:
- Pruebas de transfección en células EC y COS.
- Análisis de la actividad del promotor RAR beta 2.
- Expresión de proteínas recombinantes y estudios de interacción.
Principales resultados:
- El TFIID humano recombinante (hTFIID) y el RAR cooperan en la transactivación dependiente de la AR del promotor RAR beta 2 en las células EC.
- El dominio central de hTFIID es suficiente para la transcripción mediada por RAR.
- El TFIID de Drosophila, pero no el TFIID de levadura, puede sustituir al hTFIID.
- La expresión ectópica de la proteína E1A es necesaria para la cooperación hTFIID y RAR en las células COS.
Conclusiones:
- Se propone un modelo donde el RAR activado interactúa con el hTFIID a través de una actividad similar a la E1A en las células EC para regular la transcripción del promotor RAR beta 2.
- Esta interacción es esencial para la diferenciación inducida por la AR en las células EC.
Videos de Conceptos Relacionados
00:49Ligand Binding and Linkage
Allosteric proteins have more than one ligand binding site; the binding of a ligand to any of these sites influences the binding of ligands to the other sites. When a protein is allosteric, its binding sites are called coupled or linked. In the case of enzymes, the site that binds to the substrate is known as the active site and the other site is known as the regulatory site. When a ligand binds to the regulatory site, this leads to conformational changes in the protein that can influence the...
02:26tRNA Activation
Aminoacyl-tRNA synthetases are present in both eukaryotes and bacteria. Though eukaryotes have 20 different aminoacyl-tRNA synthetases to couple to 20 amino acids, many bacteria do not have genes for all of these aminoacyl-tRNA synthetases. Despite this, they still use all 20 amino acids to synthesize their proteins. For instance, some bacteria do not have the gene encoding the enzyme that couples glutamine with its partner tRNA. In these organisms, one enzyme adds glutamic acid to all of the...
02:42Eukaryotic Transcription Activators
Transcription activators are proteins that promote the transcription of genes from DNA to RNA. In most cases, these proteins contain two separate domains ‒ a domain that binds to DNA and a domain for activating transcription; however, in some cases, a single domain is responsible for both binding and activation of transcription, as seen in the glucocorticoid receptor and MyoD.
The binding domains are capable of recognizing and interacting with regulatory sequences on the DNA. These domains are...
The binding domains are capable of recognizing and interacting with regulatory sequences on the DNA. These domains are...
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...
02:26tRNA Activation
Aminoacyl-tRNA synthetases are present in both eukaryotes and bacteria. Though eukaryotes have 20 different aminoacyl-tRNA synthetases to couple to 20 amino acids, many bacteria do not have genes for all of these aminoacyl-tRNA synthetases. Despite this, they still use all 20 amino acids to synthesize their proteins. For instance, some bacteria do not have the gene encoding the enzyme that couples glutamine with its partner tRNA. In these organisms, one enzyme adds glutamic acid to all of the...
01:16Transduction
Among the three main modes of HGT—transformation, conjugation, and transduction—transduction is unique in that it is mediated by bacteriophages, or bacterial viruses.Transduction occurs in two ways. Generalized transduction occurs during the lytic cycle of a bacteriophage infection. In this process, bacteriophages infect bacterial cells, replicate within them, and ultimately cause cell lysis, releasing newly assembled virions. Occasionally, random fragments of the bacterial genome are...