NAD signalling
Dr Lee Hunt
- 0114 222 4244
- l.hunt@sheffield.ac.uk
In animals NAD can be degraded by several signalling enzymes including ribosyl cyclase, PARP and Sir2. NAD hydrolysis by Sir2 histone deacetylases catalyses the removal of an acetyl group from histones to form O acetyl-ADP ribose and nicotinamide . In yeast and animals Sir2s have been implicated in life span extension, apoptosis and oxidative stress but a role in plants has yet to be identified. A by- product of NAD hydrolysis is nicotinamide, which is an in vitro inhibitor of several NAD degrading enzymes, and an in vivo regulator of Sir2 activity in yeast. We are characterising plant homologues and investigating their roles in stress signalling in Arabidopsis Our experiments with a mutant in a nicotinamidase shows a role in seed germination and dormancy.
- Researchers : Lee Hunt.
- Collaborators : Mike Holdsworth, University of Nottingham
NAD metabolism in Arabidopsis (adapted from Hunt et al., 2004)
PARP promoter GUS fusion showing embryo specific expression
Selected Publications
Hunt L & Gray JE The relationship between pyridine nucleotides and seed dormancy. New Phytologist 181(1) 62-70 2009. Hunt, L Holdsworth, MJ, Gray, JE. (2007). Nicotinamidase activity is important for germination. Plant Journal 51(3) 341-351. Hunt L, Lerner, F & Zeigler M.(2004). NAD- new roles in signalling and gene regulation in plants. New Phytologist, 163, 31-44.