Reference

portadaARSAntioxid Redox Signal. 2016 Feb 1; 24(4): 173–185. doi:10.1089/ars.2014.6175

Authors

Botello-Morte Laura, Pellicer Silvia, Sein-Echaluce Violeta C., Contreras Lellys M., Neira José Luis, Abián Olga, Velázquez-Campoy Adrián, Peleato María Luisa, Fillat María F., and Bes María Teresa

Abstract

BACKGROUND:
Aims: The ferric uptake regulator (Fur) is the main transcriptional regulator of genes involved in iron homeostasis in most prokaryotes. FurA from Anabaena sp. PCC 7120 contains five cysteine residues, four of them arranged in two redox-active CXXC motifs. The protein needs not only metal but also reducing conditions to remain fully active in vitro. Through a mutational study of the cysteine residues present in FurA, we have investigated their involvement in metal and DNA binding. Results: Residue C101 that belongs to a conserved CXXC motif plays an essential role in both metal and DNA binding activities in vitro. Substitution of C101 by serine impairs DNA and metal binding abilities of FurA. Isothermal titration calorimetry measurements show that the redox state of C101 is responsible for the protein ability to coordinate the metal corepressor. Moreover, the redox state of C101 varies with the presence or absence of C104 or C133, suggesting that the environments of these cysteines are mutually interdependent. Innovation: We propose that C101 is part of a thiol/disulfide redox switch that determines FurA ability to bind the metal corepressor. Conclusion: This mechanism supports a novel feature of a Fur protein that emerges as a regulator, which connects the response to changes in the intracellular redox state and iron management in cyanobacteria.

Description

Este trabajo propone un nuevo mecanismo de acción para el regulador global FurA, que en ciertas condiciones puede actuar como un sensor redox basado en sus motivos CXXC para modular su actividad transcripcional. La Cys101, esencial para unión al DNA y al metal correpresor, parece ser responsable de la dimerización de FurA en solución. Además, la Cys104 constituye junto con la Cys101 o la Cys133 un interruptor redox que coordina el estado redox y la actividad del regulador.

 

fotogruposept

 

REFERENCIA DEL GRUPO INVESTIGADOR

El grupo "Regulación génica y fisiología de cianobacterias" (BIFI – Universidad de Zaragoza) investiga la regulación del metabolismo del hierro y su relación con el metabolismo nitrogenado, los mecanismos de defensa el estrés oxidativo y la producción de cianotoxinas. Actualmente nuestro trabajo está centrado en la caracterización funcional de la superfamilia de reguladores FUR (ferric uptake regulator) en cianobacterias y diversos patógenos de interés clínico y ambiental.

Descárgate este artículo aquí.

Did you publish an interesting article recently?

Send it through our application form and we will contact you. Age limit: 32.

The selected articles will participate at the Award to the best article of young people of the SEBBM which will be given during SEBBM conference, that will take place at Spain (free registration, travel and accommodation).

More articles of the month

Mechanisms of bacterial membrane permeabilization by crotalicidin (Ctn) and its fragment Ctn(15-34), antimicrobial peptides from rattlesnake venom.

04-04-2018

La crotalicidina, un péptido del veneno de una serpiente de cascabel, tiene entre otras propiedades una potente acción antimicrobiana. Un fragmento resultante de la disección racional del péptido nativo presenta...

Read more

Functional optimization of broadly neutralizing HIV-1 antibody 10E8 by promoting membrane interactions

01-03-2018

El anticuerpo 10E8 representa uno de los anticuerpos anti-VIH con mayor cobertura de neutralización y potencia descrito a día de hoy. Su epítopo se localiza en una región próxima a...

Read more

Molecular mechanism for the subversion of the retromer coat by the Legionella effector RidL

01-02-2018

La legionelosis o enfermedad del legionario es una neumonía potencialmente fatal, causada por la bacteria Legionella pneumophila. Durante la infección, la bacteria trasloca un gran número de proteínas, llamadas efectores...

Read more

Late rDNA Condensation Ensures Timely Cdc14 Release and Coordination of Mitotic Exit Signaling with Nucleolar Segregation

01-01-2018

El nucléolo, además de su función esencial en la biogénesis de los ribosomas, juega también un papel importante en múltiples procesos celulares. Así, en este orgánulo se mantienen secuestradas proteínas clave para...

Read more

Inactivation of Capicua in adult mice causes T-cell lymphoblastic lymphoma

01-12-2017

CIC (also known as Capicua) is a transcriptional repressor negatively regulated by RAS/MAPK signaling. Whereas the functions of Cic have been well characterized in Drosophila, little is known about its...

Read more

Physical proximity of chromatin to nuclear pores prevents harmful R loop accumulation contributing to maintain genome stability

01-11-2017

During transcription, the mRNA may hybridize with DNA, forming an R loop, which can be physiological or pathological, constituting in this case a source of genomic instability. To understand the...

Read more

Whi7 is an unstable cell-cycle repressor of the Start transcriptional program

01-10-2017

Start is the main decision point in eukaryotic cell cycle in which cells commit to a new round of cell division. It involves the irreversible activation of a transcriptional program...

Read more

CTCF orchestrates the germinal centre transcriptional program and prevents premature plasma cell differentiation

01-09-2017

In germinal centres (GC) mature B cells undergo intense proliferation and immunoglobulin gene modification before they differentiate into memory B cells or long-lived plasma cells (PC). GC B-cell-to-PC transition involves...

Read more

Catalytic Cycle of the N-Acetylglucosaminidase NagZ from Pseudomonas aeruginosa

01-08-2017

The N-acetylglucosaminidase NagZ of Pseudomonas aeruginosa catalyzes the first cytoplasmic step in recycling of muropeptides, cell-wall-derived natural products. This reaction regulates gene expression for the β-lactam resistance enzyme, β-lactamase. The...

Read more

Crebbp loss cooperates with Bcl2 overexpression to promote lymphoma in mice.

01-07-2017

CREBBP is targeted by inactivating mutations in follicular lymphoma (FL) and diffuse large B-cell lymphoma (DLBCL). Here, we provide evidence from transgenic mouse models that Crebbp deletion results in deficits...

Read more

Protector Members