NtrC

NtrC

NtrC (proteína C reguladora de nitrógeno) es una proteína dimérica codificable en Escherichia coli que al unirse a un amplificador activa la transcripción del gen glnA, el cual codifica la enzima glutamina sintetasa que cataliza la reacción de síntesis del aminoácido glutamina a partir de ácido glutámico y amoníaco.[1]

Mecanismo de acción

La proteína activadora NtrC se encuentra regulada por la proteincinasa NtrB formando un sistema regulador de dos componentes.
Como respuesta a la disminución de glutamina en el medio externo, la proteincinasa NtrB fosforila residuos de la NtrC induciendo un cambio conformacional que permite su unión con un amplificador. La NtrC fosforilada se une a la ARN polimerasa unida al factor σ54, localizada a varios pares de bases de distancia (unida al promotor), generandose un bucle en el ADN. La actividad ATPasa de la proteína NtrC fosforilada activa la trascripción de gen al permitir a la ARNpolimerasa-σ54 separar las hebras de ADN.[1]

Referencias

  1. ↑ a b LODISH, BERK, MATSUDAIRA, KAISER, KRIEGER, SCOTT, ZIPURSKY, DARNELL (2005) (en español). "Biología Celular y Molecular (5ta. edición)". Panamericana. ISBN-10 950-06-1374-3. 

Enlaces externos

«glnA - glutamine sintetasa». WikiGenes.


Wikimedia foundation. 2010.

Игры ⚽ Нужно решить контрольную?

Mira otros diccionarios:

  • NtrC — (Nitrogen regulatory protein C) is the name of the protein necessary for the prokaryotic regulation transcription factor sigma N (sigma 54) to form an open complex with RNA polymerase in order to activate glnA transcription. The open > closed… …   Wikipedia

  • NTRC — National Teacher Recruitment Clearinghouse (Business » Positions) National Teacher Recruitment Clearinghouse (Business » Firms) …   Abbreviations dictionary

  • NTRC — National Toxins Research Center …   Medical dictionary

  • NTRC — abbr. National Transportation Research Center …   Dictionary of abbreviations

  • NTRC — • National Toxins Research Center …   Dictionary of medical acronyms & abbreviations

  • National Transportation Research Center — For the sigma N transcription factor activator protein in prokaryotes, see NtrC The National Transportation Research Center (NTRC) is an institution, located in Knoxville, Tennessee, that conducts research and development aimed at increasing the… …   Wikipedia

  • Texas A&M University–Kingsville — Infobox University name = Texas A M University–Kingsville established = 1925 type = Public University president = Steven H. Tallant, Ph.D. campus = 1,600 acres (6.5 km²) city = Kingsville state = Texas country = United States students = 6,662… …   Wikipedia

  • Vietnam Veterans of America Foundation — Articleissues advert = August 2007 cleanup = August 2007 confusing = August 2007 copyedit = August 2007 tone = August 2007 wikify = August 2007The Vietnam Veterans of America Foundation (VVAF), [ [http://www.veteransforamerica.org/about/ Veterans …   Wikipedia

  • Nikola Tesla — Tesla, aged 37, 1893, photo by Sar …   Wikipedia

  • List of United States federal agencies — This is an incomplete list of United States federal agencies. All are agencies within one of the three branches of the United States government. Executive Branch Departmental agencies are organized by department. Independent agencies of the… …   Wikipedia

Compartir el artículo y extractos

Link directo
… Do a right-click on the link above
and select “Copy Link”