Two Homologous Putative Protein Tyrosine Phosphatases, OsPFA-DSP2 and AtPFA-DSP4, Negatively Regulate the Pathogen Response in Transgenic Plants

Abstract

Protein phosphatases, together with protein kinases, regulate protein phosphorylation and dephosphorylation, and play critical roles in plant growth and biotic stress responses. However, little is known about the biological functions of plant protein tyrosine dual-specificity phosphatase (PFA-DSP) in biotic stresses. Here, we found that OsPFA-DSP2 was mainly expressed in calli, seedlings, roots, and young panicles, and localized in cytoplasm and nucleus. Ectopic overexpression of OsPFA-DSP2 in rice increased sensitivity to Magnaporthe grisea (M. grisea Z1 strain), inhibited the accumulation of hydrogen peroxide (H2O2) and suppressed the expression of pathogenesis-related (PR) genes after fungal infection. Interestingly, transgenic Arabidopsis plants overexpressing AtPFA-DSP4, which is homologous to OsPFA-DSP2, also exhibited sensitivity to Pseudomonas syringae pv. tomato DC3000 (Pst DC3000), reduced accumulation of H2O2 and decreased photosynthesic capacity after infection compared with Col-0. These results indicate that OsPFA-DSP2 and AtPFA-DSP4 act as negative regulators of the pathogen response in transgenic plants.

The Role of Autophagy in Chloroplast Degradation and Chlorophagy in Immune Defenses during Pst DC3000 (AvrRps4) Infection

“…Additionally it caused a strong HR that becomes macroscopically apparent on day 1 post-infection (pi) at region I (the site of pathogen infection) (Figure 1A). Changes in Fv/Fm were already detectable after 3 hpi at region I. Twenty-four hpi there was also a remarkable decrease in Fv/Fm at the site of the MgCl 2 treatment (data not shown) consistent with previous studies [20,21]. The meaning of Fv/Fm is maximum fluorescence yield of photosystem II (PS II).…”

Role of Protein Tyrosine Phosphatases in Plants

“…Presently, MAPKs have been characterized in higher plants and the importance of Tyr phosphorylation in plant cells cannot be ignored. MAPKs play a vital role in the signal transduction pathways in higher plants [ 124 ]. It is well known that PTPs plays a major role in regulation of MAPK cascade and their expression is often induced by various stress signals [ 124 ].…”

“…MAPKs play a vital role in the signal transduction pathways in higher plants [ 124 ]. It is well known that PTPs plays a major role in regulation of MAPK cascade and their expression is often induced by various stress signals [ 124 ]. For example, Arabidopsis MPK6 is activated by various pathogenic stimuli and abiotic stress signals [ 126 , 127 ].…”

High-resolution mapping of genes involved in plant stage-specific partial resistance of barley to leaf rust

“…Several of these genes belong to gene families involved in resistance in other plant pathogen systems, including an oxidoreductase (Montesano et al 2003 ), an aspartokinase (Stuttmann et al 2011 ) and a proteasome subunit (Yao et al 2012 ), which are conserved between rice and B. distachyon . There is also a glutathione S-transferase (Dean et al 2005 ) and a transcription factor BTF3 (Huh et al 2012 ) found only in the rice syntenic region, as well as a protein kinase C (Subramaniam et al 1997 ), protein tyrosine phosphatases (He et al 2012 ), glycosyltransferases (Langlois-Meurinne et al 2005 ) and a NBS-LRR gene (Loutre et al 2009 ) found only in the B. distachyon syntenic region. There is no favourite candidate gene in the interval for the moment.…”