Jonathan D G Jones

..An absence of obvious developmental defects in null Arabidopsis rar1 mutants favors the notion that, in contrast, RAR1 does not play a fundamental role in plant development...

..A detailed understanding of plant immune function will underpin crop improvement for food, fibre and biofuels production...

..It would be perverse to spurn this approach at a time when we need every tool in the toolbox to ensure adequate food production in the short, medium and long term...

..Recognition of the Cf-9 C-terminus by CITRX is necessary and sufficient for this negative regulation. This is the first study that implicates thioredoxin activity in the regulation of plant disease resistance...

..We propose that perturbed cell wall biosynthesis may activate plant defence and provide a rationale for the cie1 and the mur3 knockout phenotypes...

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..All these data suggest that heterologous expression of an R gene can result in activation of cell death even in the absence of its cognate avirulence product, and provides a system for studying the RPS4 domains required for HR...

..Interestingly, there is an overlap between the Cf-4 and Cf-9 specificity-determining residues, precluding a protein with dual specificity...

..However, extensive characterization of the Cf-4 complex revealed essentially identical characteristics to the Cf-9 complex and significant differences from the CLV2 complex...

..We show here that Avr2 binds and inhibits Rcr3 and propose that the Rcr3-Avr2 complex enables the Cf-2 protein to activate an HR...

..These data reveal a previously unsuspected role of a specific subset of ER-QC machinery components for PRR accumulation in plant innate immunity...

..1, suggesting either that this strong resistance gene has been maintained since a common ancestor, due to selection pressure for blight resistance, or that genetic exchange between S. venturii and S. phureja has occurred at some time...

..Interestingly, the catalytic activities of both CITRX and ACIK1 are not required for their interaction...

..We propose that miR393 levels can fine-tune plant defences and prioritize resources...

..Moreover, SGT1b and RAR1 contribute additively to RPP5-mediated pathogen recognition. These data imply both operationally distinct and cooperative functions of SGT1 and RAR1 in plant disease resistance...

..This is consistent with previous observations that the TIR domain itself is insufficient to induce cell death upon transient expression...

..We also show that Nt CMPG1 is involved in the Pto/AvrPto and Inf1 responses. In summary, we show that the E3 ligase Nt CMPG1 is essential for plant defense and disease resistance...

..XopO is also processed into a smaller form in N. benthamiana, similar to AvrRPS4, suggesting that a common mechanism is involved in activation of the virulence activities of both AvrRPS4 and XopO...

..They also provide an unexpected differential requirement for ER-QC and N-glycosylation components by two closely related receptors...

..Repression of auxin signaling restricts P. syringae growth, implicating auxin in disease susceptibility and miRNA-mediated suppression of auxin signaling in resistance...

..syringae strains that are pathogenic in Arabidopsis carry truncated hopAS1 variants of forms, demonstrating that HopAS1-triggered immunity plays an important role in Arabidopsis NHR to a broad-range of P. syringae strains...

..Here, we review recent advances made in understanding the role of these hormones in modulating plant defence responses against various diseases and pests...

..It also provides a proof-of-principle demonstration that the method could be used to generate new variation in elite lines of maize...

..We also compared FLARE gene sets and genes induced in basal or gene-for-gene interactions upon different Pseudomonas syringae treatments, and infer that Pseudomonas syringae pv tomato represses the flagellin-initiated defense response...

..These data indicate that CDPK and MAPK pathways do not function independently and that a concerted activation of both pathways controls response specificity to biotic and abiotic stress...

..Our findings show that silencing SGT1 affects diverse types of disease resistance in plants and support the idea that R protein-mediated and nonhost resistance may involve similar mechanisms...

..Two-phase partitioning and sucrose density gradient sedimentation established that RPP1A resides in the endoplasmic reticulum and/or Golgi apparatus...

..These draft assemblies are useful for exploring an organism's proteomic potential, at a very economic low cost...

..These findings suggest an explanation for why the necrotrophic fungus Gibberella fujikuroi, causal agent of the foolish-seedling disease of rice, makes gibberellin...

..Thus, Cf-9-dependent defense signaling and CLV2-dependent regulation of meristem development seem to be accomplished via distinct mechanisms, despite the structural similarity of their key components Cf-9 and CLV2...

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..Thus, the VIGS system is an effective method of rapidly assessing gene function in potato...

..Plant pathogen effectors have now been shown to mimic plant transcription factors and turn on genes that help the pathogen. Some plants, however, have evolved to use these pathogen-derived transcription factors to turn on defence...

..The roles of subcellular changes and effector localization, with specific reference to the potential role of HaRxL17 in plant cell membrane trafficking, are discussed with respect to Hpa virulence...

..This indicates that NADPH oxidases control development by making ROS that regulate plant cell expansion through the activation of Ca2+ channels...

..These mechanisms are not only relevant to plant pathogenic oomycetes but also to human pathogens within the Chromalveolata...

..Furthermore, loss-of-function and gain-of-function studies revealed that signalling pathways leading to cold, salt, drought or pathogen resistance are mediated by specific CDPK isoforms..

..In this article, we review the capabilities of high-throughput sequencing technologies and discuss the many options for getting useful information from the data...

..Thus, HaRxL17 that increases plant susceptibility to Hpa during both compatible and incompatible interactions, localizes around oomycete haustoria when stably expressed in Arabidopsis...

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..We show that AtPRIMER accurately found specific polymorphic markers for our linkage mapping project. AtPRIMER will therefore be useful for efficient marker development with high density and specificity...

..Our results suggest that RPP4-mediated resistance is developmentally regulated and that in cotyledons there is cross-talk between EDS1 and NDR1 signalling and processes regulating systemic acquired resistance...

..We highlight an emerging theme that positive and negative regulators of these disparate hormone signaling pathways are crucial regulatory targets of hormonal crosstalk in disease and defense...

..We propose that these hormones may influence disease outcomes through their effect on SA or JA signalling...

..We identify a conserved class of U-box ARMADILLO repeat E3 ligases that are positive regulators of cell death and defense across the Solanaceae and Brassicaceae...

..tomato DC3000 when it is sprayed on the leaf surface. Thus, flagellin perception restricts bacterial invasion, probably at an early step, and contributes to the plant's disease resistance...

..Recent research aiming to understand these pathways and their molecular components in plants are reviewed here...

..A combination of sequence and phylogenetic analysis of these predicted RLPs reveals conserved structural features of the family...

..This genome-wide collection of Arabidopsis RLP gene T-DNA insertion mutants provides a tool for future investigations into the biological roles of RLPs...

..Increased LAX3 activity reinforces the auxin-dependent induction of a selection of cell-wall-remodelling enzymes, which are likely to promote cell separation in advance of developing lateral root primordia...

..Together, these findings support a role of ACIF1/VFBs in plant defense responses...

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..parasitica isolate Emco5, ATR13Emco5 when delivered by Pst DC3000 triggered localized immunity, including HR, on Ws-0. We suggest that an additional H. parasitica Emco5 effector might suppress ATR13-triggered immunity...

..These results have implications for understanding how salicylic acid activates defense signaling in cells spatially removed from infection sites without causing cell death...

..Due to the synteny between rice and other Gramineae, this analysis should provide valuable tools for experimental studies in rice and other cereals...

..Moreover, VIGS of LeACIK1 in tomato decreased Cf-9-mediated resistance to C. fulvum, showing the importance of ACIK1 in disease resistance...

..These exciting recent reports are probably just the first examples of what lies beneath. More roles for plant proteases in defence, as well as the regulation and substrates of these enzymes, are waiting to be discovered...

..Most mutations result in single-amino-acid substitutions in their C terminus at residues that are conserved in other Cf proteins...

..The fourth cDNA, tomTHT1-4, directed synthesis of a truncated enzymatically inactive protein due to the presence of a premature stop codon...

..Taken together, these results suggest that caution should be taken when interpreting data obtained from gel filtration of LRR-containing proteins...

..These data provide direct molecular genetic and cell biological evidence that ROS are rate-limiting second messengers in ABA signaling, and that the AtrbohD and AtrbohF NADPH oxidases function in guard cell ABA signal transduction...

..Our data establish for the first time that an enzyme of trehalose metabolism is essential in plants and is implicated in the regulation of sugar metabolism/embryo development via a different mechanism to that reported in S. cerevisiae...

..This work strongly supports the idea that PPS3 is a physiological substrate of StMPK1 and is involved in cell death activated by a MAPK cascade...

..We propose that enhancing disease resistance through altered regulation of plant defense mechanisms should be more durable and publicly acceptable than engineering overexpression of antimicrobial proteins...

..We find that EDS1 is an indispensable component of RPS4 signaling and that it functions downstream of RPS4 activation but upstream of RPS4-mediated transcriptional reprogramming in the nucleus...

..SFPs identified with the gene expression array also provide an empirical hybridization polymorphism background for studies of gene expression polymorphism and are available through the genome browser http://signal.salk.edu/cgi-bin/AtSFP...

..Thus, BAK1 is not only associated with developmental regulation through the plant hormone receptor BRI1 (refs 6,7), but also has a functional role in PRR-dependent signalling, which initiates innate immunity...

..We propose that most T-DNA integrations in tomato require sequence homology between the ssT-DNA LB and plant target DNA which results in the generation of DSBs in plant chromosomal DNA...

..Multiple copies of related but distinct AVR effector paralogues might enable populations of Bgh to rapidly overcome host R genes while maintaining virulence...

..These results demonstrate that EFR is the EF-Tu receptor and that plant defense responses induced by PAMPs such as EF-Tu reduce transformation by Agrobacterium...

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..Agrobacterium tumefaciens-mediated transient expression of Hcr9-M205 in Nicotiana tabacum caused chlorosis and the accumulation of defence gene transcripts, indicating that the protein encoded by this novel Hcr9 gene is autoactive...

..parasitica. Paradoxically, although atrbohD mutation eliminated the majority of total ROI production, atrbohF mutation exhibited the strongest effect on cell death...