Poly(ADP-ribose) polymerase in plants affects energy homeostasis, cell death and stress tolerance

Plant J. 2005 Jan;41(1):95-106. doi: 10.1111/j.1365-313X.2004.02277.x.

Abstract

Plants contain two genes that code for poly(ADP-ribose) polymerase (PARP): parp1 and parp2. Both PARPs are activated by DNA damage caused by, example reactive oxygen species. Upon activation polymers of ADP-ribose are synthesized on a range of nuclear enzymes using NAD(+) as substrate. Here, we show that in plants stresses such as drought, high light and heat activate PARP causing NAD(+) breakdown and ATP consumption. When the PARP activity is reduced by means of chemical inhibitors or by gene silencing, cell death is inhibited and plants become tolerant to a broad range of abiotic stresses like high light, drought and heat. Plant lines with low poly(ADP-ribosyl)ation activity maintain under stress conditions their energy homeostasis by reducing NAD(+) breakdown and consequently energy consumption. The higher energy-use efficiency avoids the need for a too intense mitochondrial respiration and consequently reduces the formation of reactive oxygen species. From these results it can be concluded that breeding or engineering for a high energy-use efficiency under stress conditions is a valuable, but until today nearly unexploited, approach to enhance overall stress tolerance of crops.

MeSH terms

  • Arabidopsis / enzymology
  • Arabidopsis / metabolism
  • Aspirin / pharmacology
  • Brassica napus / drug effects
  • Brassica napus / enzymology
  • Brassica napus / metabolism
  • Cell Death*
  • Homeostasis*
  • In Situ Nick-End Labeling
  • Oxidative Stress*
  • Plants / enzymology*
  • Plants / metabolism
  • Poly(ADP-ribose) Polymerases / metabolism*

Substances

  • Poly(ADP-ribose) Polymerases
  • Aspirin