Mechanisms of xylanase-induced nitric oxide and phosphatidic acid production in tomato cells

Abstract

The second messenger nitric oxide (NO), phosphatidic acid (PA) and reactive oxygen species (ROS) are involved in the plant defense response during plant-pathogen interactions. NO has been shown to participate in PA production in response to the pathogen-associated molecular pattern xylanase in tomato cell suspensions. Defense responses downstream of PA include ROS production. The goal of this work was to study the signaling mechanisms involved in PA production during the defense responses triggered by xylanase and mediated by NO in the suspension-cultured tomato cells. We analyzed the participation of protein kinases, guanylate cyclase and the NO-mediated posttranslational modification S-nitrosylation, by means of pharmacology and biochemistry. We showed that NO, PA and ROS levels are significantly diminished by treatment with the general protein kinase inhibitor staurosporine. This indicates that xylanase-induced protein phosphorylation events might be the important components leading to NO formation, and hence for the downstream regulation of PA and ROS levels. When assayed, a guanylate cyclase inhibitor or a cGMP analog did not alter the PA accumulation. These results suggest that a cGMP-mediated pathway is not involved in xylanase-induced PA formation. Finally, the inhibition of protein S-nitrosylation did not affect NO formation but compromised PA and ROS production. Data collectively indicate that upon xylanase perception, cells activate a protein kinase pathway required for NO formation and that, S-nitrosylation-dependent mechanisms are involved in downstream signaling leading to PA and ROS.

Nitric Oxide Production by Necrotrophic Pathogen Macrophomina phaseolina and the Host Plant in Charcoal Rot Disease of Jute: Complexity of the Interplay between Necrotroph–Host Plant Interactions

“…Zymogram analysis as well as Congo red staining of the inoculated birch wood xylan agar plate revealed that the necrotrophic fungus M. phaseolina could produce highly active extracellular xylanase (Figure 7D). In fact, xylanase is known to play a vital role in presenting pathogen associated molecular pattern (PAMP) which is evident in different model systems [20], [21]. In tomato cells, NO has been shown to be involved in the induction of phosphatidic acid (PA) production in response to the PAMP xylanase [22].…”

Capping Protein Modulates Actin Remodeling in Response to Reactive Oxygen Species during Plant Innate Immunity

“…Phosphatidic acid (PA) is an abundant membrane phospholipid increasingly recognized as a signaling intermediate during innate immunity (Zhao, 2015). In rice (Oryza sativa) and tomato (Solanum lycopersicum) suspension-cultured cells, PA accumulates within a few minutes upon treatment with various MAMPs (van der Luit et al, 2000;Yamaguchi et al, 2003Yamaguchi et al, , 2005Bargmann et al, 2006;Laxalt et al, 2007;Lanteri et al, 2011;Raho et al, 2011). Nod factors have also been reported to induce PA production in vivo (den Hartog et al, 2001).…”

Cross-talk of nitric oxide and reactive oxygen species in plant programed cell death

“…Thus, modulation of a central MAPK cascade may converge both H 2 O 2 and NO signaling pathways activated in response to pathogen infection. In tomato cell suspensions, upon xylanase perception, cells activate a protein kinase pathway required for NO formation and S -nitrosylation-dependent mechanisms which are involved in downstream signaling, leading to production of polyamine and ROS production (Lanteri et al, 2011). …”