Toggle Main Menu Toggle Search

Open Access padlockePrints

Kinetic analysis of the interaction between the QutA and QutR transcription-regulating proteins

Lookup NU author(s): Dr Carys WattsORCiD, Dr Heather Lamb, Professor Alastair Hawkins


Full text for this publication is not currently held within this repository. Alternative links are provided below where available.


The QutR protein is a multidomain repressor protein that interacts with the QutA activator protein. Both proteins are active in the signal transduction pathway that regulates transcription of the quinic acid utilization (qut) gene cluster of the microbial eukaryote Aspergillus nidulans. In the presence of quinate, production of mRNA from the eight genes of the qut pathway is stimulated by the QutA activator protein. The QutR protein plays a key role in signal recognition and transduction, and a deletion analysis has shown that the N-terminal 88 amino acids are sufficient to inactivate QutA function in vivo. Using surface plasmon resonance we show here that the N-terminal 88 amino acids of QutR are able to bind in vitro to a region of QutA that genetic analysis has previously implicated in transcription activation. We further show that increasing the concentration of a full-length (missense) mutant QutR protein in the original mutant strain can restore its repressing function. This is interpreted to mean that the qutR mutation in this strain increases the equilibrium dissociation constant for the interaction between QutA and QutR. We propose a model in which the QutA and QutR proteins are in dynamic equilibrium between bound (transcriptionally inactive) and unbound (transcriptionally active) states. © 2002 Wiley-Liss, Inc.

Publication metadata

Author(s): Hawkins AR; Watts C; Lamb HK; Si-Hoe SM; Levett LJ; Coggins JR

Publication type: Article

Publication status: Published

Journal: Proteins: Structure, Function and Genetics

Year: 2002

Volume: 48

Issue: 2

Pages: 161-168

ISSN (print): 0887-3585

ISSN (electronic):

Publisher: John Wiley & Sons, Inc.


DOI: 10.1002/prot.10157

PubMed id: 12112685


Altmetrics provided by Altmetric