Journal
MOLECULAR CELL
Volume 38, Issue 4, Pages 563-575Publisher
CELL PRESS
DOI: 10.1016/j.molcel.2010.05.006
Keywords
-
Categories
Funding
- U.S. Department of Energy
- National Institutes of Health
- Lang Award
- Biotechnology and Biological Sciences Research Council (BBSRC) [P19928]
- Biotechnology and Biological Sciences Research Council [P19928] Funding Source: researchfish
Ask authors/readers for more resources
Nicotinamide adenine dinucleotides have emerged as key signals of the cellular redox state. Yet the structural basis for allosteric gene regulation by the ratio of reduced NADH to oxidized NAD(+) is poorly understood. A key sensor among Gram-positive bacteria, Rex represses alternative respiratory gene expression until a limited oxygen supply elevates the intracellular NADH:NAD(+) ratio. Here we investigate the molecular mechanism for NADH/NAD(+) sensing among Rex family members by determining structures of Thermus aquaticus Rex bound to (1) NAD(+), (2) DNA operator, and (3) without ligand. Comparison with the Rex/NADH complex reveals that NADH releases Rex from the DNA site following a 400 closure between the dimeric subunits. Complementary site-directed mutagenesis experiments implicate highly conserved residues in NAD-responsive DNA-binding activity. These rare views of a redox sensor in action establish a means for slight differences in the nicotinamide charge, pucker, and orientation to signal the redox state of the cell.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available