Video Experimental Relacionado
Updated: Jul 11, 2026
09:26
DNA-Tethered RNA Polymerase for Programmable In vitro Transcription and Molecular Computation
Published on: December 29, 2021
Promotor T7 atado al azobenzeno para la fotorregulación eficiente de la transcripción
Mingzhe Liu1, Hiroyuki Asanuma, Makoto Komiyama
1Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904, Japan.
Journal of the American Chemical Society
|January 19, 2006
Resumen
Los investigadores desarrollaron una transcripción fotocontrolada utilizando el azobenzeno en el promotor T7. La introducción de azobenzeno permitió que la luz regulara la actividad de la T7 ARN polimerasa (T7 RNAP), mejorando la eficiencia de la transcripción.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- La bioquímica es la bioquímica.
- Biología sintética Biología sintética.
Sus antecedentes:
- El control de la transcripción génica con estímulos externos es crucial para las aplicaciones de biología sintética.
- La fotorregulación ofrece un preciso control temporal y espacial de los procesos biológicos.
- El promotor T7 es un sistema ampliamente utilizado para la expresión génica de alto nivel.
Objetivo del estudio:
- Para diseñar el promotor T7 para la transcripción fotocontrolada utilizando azobenzeno.
- Para investigar el efecto de la posición de azobenzeno en la actividad de la T7 ARN polimerasa (T7 RNAP).
- Para lograr un fotocontrol mejorado a través de efectos sinérgicos de múltiples modificaciones de azobenzeno.
Principales métodos:
- Modificación química del promotor T7 con azobenzeno en regiones específicas (-7 a -11 y -1 a -4).
- Irradiación UV para inducir la cis-isomerización del azobenzeno y controlar la transcripción.
- Análisis cinético (determinación de Km y kcat) para dilucidar el mecanismo de fotorregulación.
Principales resultados:
- La introducción de un solo azobenceno suprimió la transcripción en la forma trans y la mejoró en la forma cis (aumento de 1,5 a 2,0 veces).
- El azobenzeno en la región de unión al bucle afectó a Km, mientras que en la región de desenrollo afectó a kcat.
- La doble modificación de azobenzeno en regiones distintas produjo un aumento sinérgico de 7,6 veces en la transcripción tras la irradiación UV.
Conclusiones:
- La incorporación de azobenzeno proporciona un fotocontrol efectivo de la transcripción del ARNAP T7.
- La posición del azobenzeno influye críticamente en los parámetros cinéticos de la regulación transcripcional.
- La acción cooperativa de dos azobenzenos en regiones promotoras específicas permite una fotorregulación robusta y mejorada.
Videos de Conceptos Relacionados
02:36Transfer RNA Synthesis
One of the unique features of tRNA is the presence of modified bases. In some tRNAs, modified bases account for nearly 20% of the total bases in the molecule. Altogether, these unusual bases protect the tRNA from enzymatic degradation by RNases.
Each of these chemical modifications is carried by a specific enzyme, post-transcription. All of these enzymes have unique base and site-specificity. Methylation, the most common chemical modification, is carried by at least nine different enzymes, with...
Each of these chemical modifications is carried by a specific enzyme, post-transcription. All of these enzymes have unique base and site-specificity. Methylation, the most common chemical modification, is carried by at least nine different enzymes, with...
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...
02:23Master 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...
02:42Transcription Attenuation in Prokaryotes
Transcriptional attenuation occurs when RNA transcription is prematurely terminated due to the formation of a terminator mRNA hairpin structure. Bacteria use these hairpins to regulate the transcription process and control the synthesis of several amino acids including histidine, lysine, threonine, and phenylalanine. Transcription attenuation takes place in the non-coding regions of mRNA.
There are several different mechanisms used to attenuate transcription. In ribosome mediated...
There are several different mechanisms used to attenuate transcription. In ribosome mediated...
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...
02:23Master 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...