Functional Divergence of Two Secreted Immune Proteases of Tomato
Ilyas, M. ; Hörger, A.C. ; Bozkurt, T.O. ; Burg, H.A. van den; Kaschani, F. ; Kaiser, M. ; Belhaj, K. ; Smoker, M. ; Joosten, M. ; Kamoun, S. ; Hoorn, R.A.L. van der - \ 2015
Current Biology 25 (2015)17. - ISSN 0960-9822 - p. 2300 - 2306.
cf-2-dependent disease resistance - pathogen effectors - transcription factors - provides insights - genome sequence - plant-pathogens - gene - defense - target - specialization
Rcr3 and Pip1 are paralogous secreted papain-like proteases of tomato. Both proteases are inhibited by Avr2 from the fungal pathogen Cladosporium fulvum, but only Rcr3 acts as a co-receptor for Avr2 recognition by the tomato Cf-2 immune receptor [ 1, 2, 3 and 4]. Here, we show that Pip1-depleted tomato plants are hyper-susceptible to fungal, bacterial, and oomycete plant pathogens, demonstrating that Pip1 is an important broad-range immune protease. By contrast, in the absence of Cf-2, Rcr3 depletion does not affect fungal and bacterial infection levels but causes increased susceptibility only to the oomycete pathogen Phytophthora infestans. Rcr3 and Pip1 reside on a genetic locus that evolved over 36 million years ago. These proteins differ in surface-exposed residues outside the substrate-binding groove, and Pip1 is 5- to 10-fold more abundant than Rcr3. We propose a model in which Rcr3 and Pip1 diverged functionally upon gene duplication, possibly driven by an arms race with pathogen-derived inhibitors or by coevolution with the Cf-2 immune receptor detecting inhibitors of Rcr3, but not of Pip1.
Host Protein BSL1 Associates with Phytophthora infestans RXLR Effector AVR2 and the Solanum demissum Immune Receptor R2 to Mediate Disease Resistance
Saunders, D.G.O. ; Breen, S. ; Win, J. ; Schornack, S. ; Hein, I. ; Bozkurt, T.O. ; Champouret, N. ; Vleeshouwers, V.G.A.A. ; Birch, P.R.J. ; Gilroy, E.M. ; Kamoun, S. - \ 2012
The Plant Cell 24 (2012)8. - ISSN 1040-4651 - p. 3420 - 3434.
nicotiana-benthamiana - plant transformation - avirulence genes - cell-death - arabidopsis - potato - activation - expression - virulence - target
Plant pathogens secrete effector proteins to modulate plant immunity and promote host colonization. Plant nucleotide binding leucine-rich repeat (NB-LRR) immunoreceptors recognize specific pathogen effectors directly or indirectly. Little is known about how NB-LRR proteins recognize effectors of filamentous plant pathogens, such as Phytophthora infestans. AVR2 belongs to a family of 13 sequence-divergent P. infestans RXLR effectors that are differentially recognized by members of the R2 NB-LRR family in Solanum demissum. We report that the putative plant phosphatase BSU-LIKE PROTEIN1 (BSL1) is required for R2-mediated perception of AVR2 and resistance to P. infestans. AVR2 associates with BSL1 and mediates the interaction of BSL1 with R2 in planta, possibly through the formation of a ternary complex. Strains of P. infestans that are virulent on R2 potatoes express an unrecognized form, Avr2-like (referred to as A2l). A2L can still interact with BSL1 but does not promote the association of BSL1 with R2. Our findings show that recognition of the P. infestans AVR2 effector by the NB-LRR protein R2 requires the putative phosphatase BSL1. This reveals that, similar to effectors of phytopathogenic bacteria, recognition of filamentous pathogen effectors can be mediated via a host protein that interacts with both the effector and the NB-LRR immunoreceptor.
Activation of antioxidant response element in mouse primary cortical cultures with sesquiterpene lactones isolated from Tanacetum parthenium
Fischedick, J.T. ; Standiford, M. ; Johnson, D.A. ; Vos, R.C.H. de; Todorovic, S. ; Banjanac, T. ; Verpoorte, R. ; Johnson, J.A. - \ 2012
Planta Medica 78 (2012)16. - ISSN 0032-0943 - p. 1725 - 1730.
biomimetic transformations - neurodegenerative disease - parthenolide - santamarine - anticancer - compositae - feverfew - pathway - target - cells
Tanacetum parthenium produces biologically active sesquiterpene lactones (SL). Nuclear factor E2-related factor 2 (Nrf2) is a transcription factor known to activate a series of genes termed the antioxidant response element (ARE). Activation of Nrf2/ARE may be useful for the treatment of neurodegenerative disease. In this study we isolated 11 SL from T. parthenium with centrifugal partition chromatography and semipreparative HPLC. Compounds were screened in vitro for their ability to activate the ARE on primary mouse cortical cultures as well as for their toxicity towards the cultures. All SL containing the a-methylene-¿-lactone moiety were able to activate the ARE and cause cellular toxicity. The structure-activity relationship among the SL isolated indicates that the guaianolides were more active and when lacking the endoperoxide functionality less toxic then the germacranolides.
Validation of automated Library-Based Qualitative Screening of Pesticides by Comprehensive Two-Dimensional Gas Chromatography/Time-of-Flight Mass Spectrometry
Mol, J.G.J. ; Kamp, H.J. van der; Weg, G. van der; Lee, M.K. van der; Punt, A.M. ; Rijk, T.C. de - \ 2011
Journal of AOAC International 94 (2011)6. - ISSN 1060-3271 - p. 1722 - 1740.
large-volume injection - spectral deconvolution - residue analysis - identification system - organic contaminants - time - vegetables - fruits - target - optimization
A method for automated detection and reporting of pesticides in plant materials based on comprehensive two-dimensional GC/time-of-flight MS with library-based detection by software has been developed and validated. Optimum settings for detection parameters such as spectral match threshold and first and second dimension retention time tolerances were assessed with respect to occurrence of false detects and false negatives. Next the method was validated following European Union guidelines established for qualitative screening of pesticides. The validation was largely done in retrospect by using data obtained for spiked samples (235 pesticides, various crops, 0.01-0.2 mg/kg) that had been analyzed previously with routine samples over a period of 18 months. At 0.01 mg/kg, the required 95% confidence level (
Angiopoietin-like 4 Interacts with Matrix Proteins to Modulate Wound Healing
Goh, Y.Y. ; Pal, M. ; Chong, H.C. ; Zhu, P. ; Tan, M.J. ; Punugu, L. ; Tan, C.K. ; Huang, R.L. ; Sze, S.K. ; Yang Tang, M.B. ; Ling Ding, J. ; Kersten, A.H. ; Tan, N.S. - \ 2010
Journal of Biological Chemistry 285 (2010)43. - ISSN 0021-9258 - p. 32999 - 33009.
activated receptor-beta/delta - human epidermal-keratinocytes - ppar-beta/delta - transcriptional control - cell-growth - expression - beta - migration - target - repair
A dynamic cell-matrix interaction is crucial for a rapid cellular response to changes in the environment. Appropriate cell behavior in response to the changing wound environment is required for efficient wound closure. However, the way in which wound keratinocytes modify the wound environment to coordinate with such cellular responses remains less studied. We demonstrated that angiopoietin-like 4 (ANGPTL4) produced by wound keratinocytes coordinates cell-matrix communication. ANGPTL4 interacts with vitronectin and fibronectin in the wound bed, delaying their proteolytic degradation by metalloproteinases. This interaction does not interfere with integrin-matrix protein recognition and directly affects cell-matrix communication by altering the availability of intact matrix proteins. These interactions stimulate integrin- focal adhesion kinase, 14-3-3, and PKC-mediated signaling pathways essential for effective wound healing. The deficiency of ANGPTL4 in mice delays wound re-epithelialization. Further analysis revealed that cell migration was impaired in the ANGPTL4-deficient keratinocytes. Altogether, the findings provide molecular insight into a novel control of wound healing via ANGPTL4-dependent regulation of cell-matrix communication. Given the known role of ANGPTL4 in glucose and lipid homeostasis, it is a prime therapeutic candidate for the treatment of diabetic wounds. It also underscores the importance of cell-matrix communication during angiogenesis and cancer metastasis.
Activation of peroxisome proliferator-activated receptor alpha in human peripheral blood mononuclear cells reveals an individual gene expression profile response
Bouwens, M. ; Afman, L.A. ; Müller, M.R. - \ 2008
BMC Genomics 9 (2008). - ISSN 1471-2164 - 9 p.
retinoid-x-receptor - fatty-acids - macrophages - metabolism - mechanisms - pathway - target - ppars - mice
Background - Peripheral blood mononuclear cells (PBMCs) are relatively easily obtainable cells in humans. Gene expression profiles of PBMCs have been shown to reflect the pathological and physiological state of a person. Recently, we showed that the nuclear receptor peroxisome proliferator-activated receptor alpha (PPARa) has a functional role in human PBMCs during fasting. However, the extent of the role of PPARa in human PBMCs remains unclear. In this study, we therefore performed gene expression profiling of PBMCs incubated with the specific PPARa ligand WY14,643. Results - Incubation of PBMCs with WY14,643 for 12 hours resulted in a differential expression of 1,373 of the 13,080 genes expressed in the PBMCs. Gene expression profiles showed a clear individual response to PPARa activation between six healthy human blood donors. Pathway analysis showed that genes in fatty acid metabolism, primarily in ß-oxidation were up-regulated upon activation of PPARa with WY14,643, and genes in several amino acid metabolism pathways were down-regulated. Conclusion - This study shows that PPARa in human PBMCs regulates fatty acid and amino acid metabolism. In addition, PBMC gene expression profiles show individual responses to WY14,643 activation. We showed that PBMCs are a suitable model to study changes in PPARa activation in healthy humans.
Protective effect of nonsteroidal anti-inflammatory drugs on colorectal adenomas is modified by a polymorphism in peroxisome proliferator-activated receptor [Delta]
Siezen, C.L.E. ; Tijhuis, M.J. ; Kram, N.R. ; Soest, E.M. van; Jong, D.J. de; Fodde, R. ; Kranen, H.J. ; Kampman, E. - \ 2006
Pharmacogenetics and Genomics 16 (2006)1. - ISSN 1744-6872 - p. 43 - 50.
cyclooxygenase-2 inhibitor - cancer - risk - chemoprevention - consumption - rofecoxib - carcinoma - polyposis - target - growth
OBJECTIVE: Nonsteroidal anti-inflammatory drugs (NSAIDs) are associated with a decreased risk of colorectal tumors. Single nucleotide polymorphisms (SNPs) in target genes of NSAID action, and their haplotypes, might modulate this protective effect. METHODS: A case-control study including 724 cases and 682 controls was used to evaluate the effect of NSAIDs on colorectal adenoma risk in The Netherlands, a country in which NSAID use is relatively low. Cases and controls were classified according to presence or absence of endoscopy-proven, pathology-confirmed colorectal adenomas, ever in their lives. Thirteen SNPs in four genes (PPARdelta, PPARgamma, PTGS1 and PTGS2) were genotyped in 787 subjects (384 cases and 403 controls). RESULTS: Compared to non-regular users (<12 times/year), regular users of NSAIDs (> or = 12 times/year) had a lower risk of colorectal adenomas (odds ratio (OR): 0.75, 95% confidence interval (CI): 0.56-0.99). The results were similar for aspirin only. We found an interaction between SNP c.-789C>T in PPARdelta and NSAID use (P=0.03). The protective effect of NSAIDs was strengthened for regular users with the PPARdelta CT or TT genotypes (OR: 0.35, 95%CI: 0.11-1.13), whereas a positive association was observed for non-regular users with these genotypes (OR: 2.24, 95%CI: 1.06-4.73) as compared to non-regular users with the CC genotype. Also, a statistically significant interaction between a major haplotype containing the minor allele of this SNP and NSAID use was observed. CONCLUSIONS: This study confirms the protective effect of NSAIDs and suggests a modulating effect of a SNP in the promoter of PPARdelta.