OPEN ACCESS ARTICLE

This Article Free via Open Access: OA OA Full Text Full Text (PDF) PPT slides of all figures Supplemental Data OA All Versions of this Article: 152/1/267    most recent pp.109.148049v2 pp.109.148049v1 Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Web of Science (1) Citing Articles via Google Scholar Google Scholar Articles by Adams-Phillips, L. Articles by Bent, A. F. Search for Related Content PubMed PubMed Citation Articles by Adams-Phillips, L. Articles by Bent, A. F. Agricola Articles by Adams-Phillips, L. Articles by Bent, A. F.

PLANTS INTERACTING WITH OTHER ORGANISMS

Disruption of Poly(ADP-ribosyl)ation Mechanisms Alters Responses of Arabidopsis to Biotic Stress^{1,[C],[W],[OA]}

Department of Plant Pathology (L.A.-P., A.G.B., A.F.B.) and Program in Cellular and Molecular Biology (A.G.B.), University of Wisconsin, Madison, Wisconsin 53706

Poly(ADP-ribosyl)ation is a posttranslational protein modification in which ADP-ribose (ADP-Rib) units derived from NAD⁺ are attached to proteins by poly(ADP-Rib) polymerase (PARP) enzymes. ADP-Rib groups are removed from these polymer chains by the enzyme poly(ADP-Rib) glycohydrolase (PARG). In animals, poly(ADP-ribosyl)ation is associated with DNA damage responses and programmed cell death. Previously, we hypothesized a role for poly(ADP-ribosyl)ation in plant defense responses when we detected defense-associated expression of the poly(ADP-ribosyl)ation-related genes PARG2 and NUDT7 and observed altered callose deposition in the presence of a chemical PARP inhibitor. The role of poly(ADP-ribosyl)ation in plant defenses was more extensively investigated in this study, using Arabidopsis (Arabidopsis thaliana). Pharmacological inhibition of PARP using 3-aminobenzamide perturbs certain innate immune responses to microbe-associated molecular patterns (flg22 and elf18), including callose deposition, lignin deposition, pigment accumulation, and phenylalanine ammonia lyase activity, but does not disrupt other responses, such as the initial oxidative burst and expression of some early defense-associated genes. Mutant parg1 seedlings exhibit exaggerated seedling growth inhibition and pigment accumulation in response to elf18 and are hypersensitive to the DNA-damaging agent mitomycin C. Both parg1 and parg2 knockout plants show accelerated onset of disease symptoms when infected with Botrytis cinerea. Cellular levels of ADP-Rib polymer increase after infection with avirulent Pseudomonas syringae pv tomato DC3000 avrRpt2⁺, and pathogen-dependent changes in the poly(ADP-ribosyl)ation of discrete proteins were also observed. We conclude that poly(ADP-ribosyl)ation is a functional component in plant responses to biotic stress.

² These authors contributed equally to the article.

The author responsible for distribution of materials integral to the findings presented in this article in accordance with the policy described in the Instructions for Authors (www.plantphysiol.org) is: Andrew F. Bent (afbent{at}wisc.edu).

^[C] Some figures in this article are displayed in color online but in black and white in the print edition.

^[W] The online version of this article contains Web-only data.

^[OA] Open Access articles can be viewed online without a subscription.

www.plantphysiol.org/cgi/doi/10.1104/pp.109.148049

^* Corresponding author; e-mail afbent{at}wisc.edu.

Received September 25, 2009; accepted October 30, 2009; published November 4, 2009.

This article has been cited by other articles:

				K. Ishikawa, K. Yoshimura, K. Harada, E. Fukusaki, T. Ogawa, M. Tamoi, and S. Shigeoka AtNUDX6, an ADP-Ribose/NADH Pyrophosphohydrolase in Arabidopsis, Positively Regulates NPR1-Dependent Salicylic Acid Signaling Plant Physiology, April 1, 2010; 152(4): 2000 - 2012. [Abstract] [Full Text] [PDF]