Related Experiment Video
Updated: Jun 21, 2026

Monitoring Protein-RNA Interaction Dynamics In Vivo at High Temporal Resolution Using χCRAC
Published on: May 9, 2020
Structure and function of an ADP-ribose-dependent transcriptional regulator of NAD metabolism
Nian Huang1, Jessica De Ingeniis, Luca Galeazzi
1Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
Abstract:
Besides its function as an essential redox cofactor, nicotinamide adenine dinucleotide (NAD) also serves as a consumable substrate for several reactions with broad impact on many cellular processes. NAD homeostasis appears to be tightly controlled, but the mechanism of its regulation is little understood. Here we demonstrate that a previously predicted bacterial transcriptional regulator, NrtR, represses the transcription of NAD biosynthetic genes in vitro. The NAD metabolite ADP-ribose functions as an activator suppressing NrtR repressor activity. The presence of high ADP-ribose levels in the cell is indicative of active NAD turnover in bacteria, which could signal the activation of NAD biosynthetic gene expression via inhibiting the repressor function of NrtR. By comparing the crystal structures of NrtR in complex with DNA and with ADP-ribose, we identified a "Nudix switch" element that likely plays a critical role in the allosteric regulation of DNA binding and repressor function of NrtR.
Related Concept Videos
Transcriptional Regulation: Riboswitches
Riboswitches
The aptamer has high specificity for a particular metabolite which allows riboswitches to specifically regulate...
RNA Polymerase II Accessory Proteins
RNA Polymerase II Accessory Proteins
Co-activators and Co-repressors
Bacterial RNA Polymerase
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...

