23 results on '"Ben M'Barek, Sarrah"'
Search Results
2. Wheat Stem Rust Detection and Race Characterization in Tunisia
- Author
-
Abdedayem, Wided, primary, Patpour, Mehran, additional, Laribi, Marwa, additional, Justesen, Annemarie F., additional, Kouki, Hajer, additional, Fakhfakh, Moez, additional, Hovmøller, Mogens S., additional, Yahyaoui, Amor H., additional, Hamza, Sonia, additional, and Ben M’Barek, Sarrah, additional
- Published
- 2023
- Full Text
- View/download PDF
3. Phenotyping Mediterranean Durum Wheat Landraces for Resistance to Zymoseptoria tritici in Tunisia
- Author
-
Ben M’Barek, Sarrah, primary, Laribi, Marwa, additional, Kouki, Hajer, additional, Castillo, Dalma, additional, Araar, Chayma, additional, Nefzaoui, Meriem, additional, Ammar, Karim, additional, Saint-Pierre, Carolina, additional, and Yahyaoui, Amor Hassine, additional
- Published
- 2022
- Full Text
- View/download PDF
4. Characterization of Mediterranean Durum Wheat for Resistance to Pyrenophora tritici-repentis
- Author
-
Laribi, Marwa, primary, Yahyaoui, Amor Hassine, additional, Abdedayem, Wided, additional, Kouki, Hajer, additional, Sassi, Khaled, additional, and Ben M’Barek, Sarrah, additional
- Published
- 2022
- Full Text
- View/download PDF
5. Additional file 2 of Deciphering resistance to Zymoseptoria tritici in the Tunisian durum wheat landrace accession ‘Agili39’
- Author
-
Ferjaoui, Sahbi, Aouini, Lamia, Slimane, Rim B., Ammar, Karim, Dreisigacker, Suzanne, Schouten, Henk J., Sapkota, Suraj, Bahri, Bochra A., Ben M’Barek, Sarrah, Visser, Richard G. F., Kema, Gert H. J., and Hamza, Sonia
- Abstract
Additional file 2: Table 1. Analysis of variance of pycnidia percent of nine Tunisian durum landraces and two modern varieties inoculated with a diverse range of twenty durum derived Zymoseptoria tritici isolates. Table 2. Pearson correlation between the different tested isolates on the 'Agili39'/khiar population RILs at the seedling and the Adult plant stages. Table 3. Linkage groups, correspondent durum wheat chromosome, the average length indicated in centimorgans (cM), number of SNPs and the average inter-loci distance (cM) in the 'Agili39'/khiar genetic linkage map. Table 4. Sequences, genetic and physical positions of the flanking markers linked to the detected QTL on the 'Agili39'/Khiar mapping population.
- Published
- 2022
- Full Text
- View/download PDF
6. Additional file 1 of Deciphering resistance to Zymoseptoria tritici in the Tunisian durum wheat landrace accession ‘Agili39’
- Author
-
Ferjaoui, Sahbi, Aouini, Lamia, Slimane, Rim B., Ammar, Karim, Dreisigacker, Suzanne, Schouten, Henk J., Sapkota, Suraj, Bahri, Bochra A., Ben M’Barek, Sarrah, Visser, Richard G. F., Kema, Gert H. J., and Hamza, Sonia
- Abstract
Additional file 1: Fig. S1. Frequency distributions of the disease severity assessed as percentage pycnidia in seedlings of the F6 recombinant inbred lines of the ‘Agili39’/Khiar population. ‘A’ and ‘K’ are referring to the ‘Agili39’and cv. Khiar parents, respectively.
- Published
- 2022
- Full Text
- View/download PDF
7. Durum Wheat Mediterranean Landraces: A Valuable Source for Resistance to Tan Spot Disease
- Author
-
Laribi, Marwa, primary, Ben M’Barek, Sarrah, additional, Fakhfakh, Moez, additional, Yahyaoui, Amor Hassine, additional, and Sassi, Khaled, additional
- Published
- 2021
- Full Text
- View/download PDF
8. Supplemental data for deciphering resistance to Zymoseptoria tritici in the Tunisian durum wheat landrace accession ‘Agili39’
- Author
-
Ferjaoui, Sahbi, Aouini, Lamia, Slimane, Rim B., Ammar, Karim, Dreisigacker, Suzanne, Schouten, Henk J., Sapkota, Suraj, Bahri, Bochra A., Ben M’Barek, Sarrah, Visser, Richard G.F., Kema, Gert H.J., Hamza, Sonia, Ferjaoui, Sahbi, Aouini, Lamia, Slimane, Rim B., Ammar, Karim, Dreisigacker, Suzanne, Schouten, Henk J., Sapkota, Suraj, Bahri, Bochra A., Ben M’Barek, Sarrah, Visser, Richard G.F., Kema, Gert H.J., and Hamza, Sonia
- Abstract
Two major and two minor QTL for seedling and adult-plant resistance to Septoria tritici blotch (STB), caused by the fungus Zymoseptoria tritici (Z. tritici) were mapped. The two mayor QTL were located on chromosome 2B, the two minor QTL on chromosomes 1A and 7A, respectively and derived from the Tunisian durum wheat landrace accession ‘Agili39’. QTL were mapped in a recombinant inbred population, phenotyped for STB resistance using a wide array of isolates and genotyped using the high density DArTSeq platform., Background Septoria tritici blotch (STB), caused by Zymoseptoria tritici (Z. tritici), is an important biotic threat to durum wheat in the entire Mediterranean Basin. Although most durum wheat cultivars are susceptible to Z. tritici, research in STB resistance in durum wheat has been limited. Results In our study, we have identified resistance to a wide array of Z. tritici isolates in the Tunisian durum wheat landrace accession ‘Agili39’. Subsequently, a recombinant inbred population was developed and tested under greenhouse conditions at the seedling stage with eight Z. tritici isolates and for five years under field conditions with three Z. tritici isolates. Mapping of quantitative trait loci (QTL) resulted in the identification of two major QTL on chromosome 2B designated as Qstb2B_1 and Qstb2B_2. The Qstb2B_1 QTL was mapped at the seedling and the adult plant stage (highest LOD 33.9, explained variance 61.6%), conferring an effective resistance against five Z. tritici isolates. The Qstb2B_2 conferred adult plant resistance (highest LOD 32.9, explained variance 42%) and has been effective at the field trials against two Z. tritici isolates. The physical positions of the flanking markers linked to Qstb2B_1 and Qstb2B_2 indicate that these two QTL are 5 Mb apart. In addition, we identified two minor QTL on chromosomes 1A (Qstb1A) and chromosome 7A (Qstb7A) (highest LODs 4.6 and 4.0, and explained variances of 16% and 9%, respectively) that were specific to three and one Z. tritici isolates, respectively. All identified QTL were derived from the landrace accession Agili39 that represents a valuable source for STB resistance in durum wheat. Conclusion This study demonstrates that Z. tritici resistance in the ‘Agili39’ landrace accession is controlled by two minor and two major QTL acting in an additive mode. We also provide evidence that the broad efficacy of the resistance to STB in ‘Agili 39’ is due to a natural pyramiding of these QTL. A sustainable use o
- Published
- 2021
9. Tagging pathogenicity genes in Fusarium graminearum using the transposon system mimp/impala
- Author
-
Dufresne, Marie, Van Der Lee, Theo, Ben M’Barek, Sarrah, Xu, X., Zhang, X., Liu, Taiguo, Zhang, Wenwei, Kema, Gert H. J., Daboussi, Marie-Josée, and Waalwijk, Cees
- Published
- 2008
- Full Text
- View/download PDF
10. Improved control of septoria tritici blotch in durum wheat using cultivar mixtures
- Author
-
Ben M'Barek, Sarrah, primary, Karisto, Petteri, additional, Abdedayem, Wided, additional, Laribi, Marwa, additional, Fakhfakh, Moez, additional, Kouki, Hajer, additional, Mikaberidze, Alexey, additional, and Yahyaoui, Amor, additional
- Published
- 2020
- Full Text
- View/download PDF
11. Stress and sexual reproduction affect the dynamics of the wheat pathogen effector AvrStb6 and strobilurin resistance
- Author
-
Kema, Gerrit H J, Mirzadi Gohari, Amir, Aouini, Lamia, Gibriel, Hesham A Y, Ware, Sarah B, van den Bosch, Frank, Manning-Smith, Robbie, Alonso-Chavez, Vasthi, Helps, Joe, Ben M'Barek, Sarrah, Mehrabi, Rahim, Diaz-Trujillo, Caucasella, Zamani, Elham, Schouten, Henk J, van der Lee, Theo A J, Waalwijk, Cees, de Waard, Maarten A, de Wit, Pierre J G M, Verstappen, Els C P, Thomma, Bart P H J, Meijer, Harold J G, Seidl, Michael F, Kema, Gerrit H J, Mirzadi Gohari, Amir, Aouini, Lamia, Gibriel, Hesham A Y, Ware, Sarah B, van den Bosch, Frank, Manning-Smith, Robbie, Alonso-Chavez, Vasthi, Helps, Joe, Ben M'Barek, Sarrah, Mehrabi, Rahim, Diaz-Trujillo, Caucasella, Zamani, Elham, Schouten, Henk J, van der Lee, Theo A J, Waalwijk, Cees, de Waard, Maarten A, de Wit, Pierre J G M, Verstappen, Els C P, Thomma, Bart P H J, Meijer, Harold J G, and Seidl, Michael F
- Published
- 2018
12. Effector discovery in the fungal wheat pathogen Zymoseptoria tritici
- Author
-
Mirzadi Gohari, Amir, Ware, Sarah B., Wittenberg, Alexander H. J., Mehrabi, Rahim, Ben M'Barek, Sarrah, Verstappen, Els C. P., van der Lee, Theo A. J., Robert, Olivier, Schouten, Henk J., de Wit, Pierre P. J. G. M., and Kema, Gert H. J.
- Subjects
Fungal Proteins ,Ascomycota ,Virulence Factors ,Gene Expression Profiling ,Genes, Fungal ,Quantitative Trait Loci ,food and beverages ,Original Articles ,Triticum - Abstract
Fungal plant pathogens, such as Zymoseptoria tritici (formerly known as Mycosphaerella graminicola), secrete repertoires of effectors to facilitate infection or trigger host defence mechanisms. The discovery and functional characterization of effectors provides valuable knowledge that can contribute to the design of new and effective disease management strategies. Here, we combined bioinformatics approaches with expression profiling during pathogenesis to identify candidate effectors of Z. tritici. In addition, a genetic approach was conducted to map quantitative trait loci (QTLs) carrying putative effectors, enabling the validation of both complementary strategies for effector discovery. In planta expression profiling revealed that candidate effectors were up-regulated in successive waves corresponding to consecutive stages of pathogenesis, contrary to candidates identified by QTL mapping that were, overall, expressed at low levels. Functional analyses of two top candidate effectors (SSP15 and SSP18) showed their dispensability for Z. tritici pathogenesis. These analyses reveal that generally adopted criteria, such as protein size, cysteine residues and expression during pathogenesis, may preclude an unbiased effector discovery. Indeed, genetic mapping of genomic regions involved in specificity render alternative effector candidates that do not match the aforementioned criteria, but should nevertheless be considered as promising new leads for effectors that are crucial for the Z. tritici-wheat pathosystem.
- Published
- 2015
13. Effector discovery in the fungal wheat pathogenZymoseptoria tritici
- Author
-
Mirzadi Gohari, Amir, primary, Ware, Sarah B., additional, Wittenberg, Alexander H. J., additional, Mehrabi, Rahim, additional, Ben M'Barek, Sarrah, additional, Verstappen, Els C. P., additional, van der Lee, Theo A. J., additional, Robert, Olivier, additional, Schouten, Henk J., additional, de Wit, Pierre P. J. G. M., additional, and Kema, Gert H. J., additional
- Published
- 2015
- Full Text
- View/download PDF
14. Transposition of a fungal MITE through the action of a Tc1-like transposase
- Author
-
Dufresne, Marie, Hua-Van, Aurelie, Abd El Wahab, Hala, Ben M'Barek, Sarrah, Vasnier, Christelle, Teysset, Laure, Kema, Gert, Daboussi, Marie-Josée, Institut de génétique et microbiologie [Orsay] (IGM), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Evolution, Génomes et Spéciation (LEGS), Centre National de la Recherche Scientifique (CNRS), Plant Research International (PRI), Wageningen University and Research Centre [Wageningen] (WUR), Institut Jacques Monod (IJM (UMR_7592)), Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), and Wageningen University and Research [Wageningen] (WUR)
- Subjects
[SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology ,food and beverages - Abstract
International audience; The mimp1 element previously identified in the ascomycete fungus Fusarium oxysporum has hallmarks of miniature inverted-repeat transposable elements (MITEs): short size, terminal inverted repeats (TIRs), structural homogeneity and a stable secondary structure. Since mimp1 has no coding capacity, its mobilization requires a transposase-encoding element. Based on the similarity of TIRs and target site preference with the autonomous Tc1-like element impala, together with a correlated distribution of both elements among the Fusarium genus, we investigated the ability of mimp1 to jump upon expression of the impala transposase provided in trans. Under these conditions, we present evidence that mimp1 transposes by a cut-an-paste mechanism into TA dinucleotides which are duplicated upon insertion. Our results also show that mimp1 reinserts very frequently, in genic regions for at least one third of the cases. We also show that the mimp1/impala double component system is fully functional in the heterologous species F. graminearum allowing the development of a highly efficient tool for gene-tagging in filamentous fungi.
- Published
- 2006
15. Finished Genome of the Fungal Wheat Pathogen Mycosphaerella graminicola Reveals Dispensome Structure, Chromosome Plasticity, and Stealth Pathogenesis
- Author
-
Goodwin, Stephen B., primary, Ben M'Barek, Sarrah, additional, Dhillon, Braham, additional, Wittenberg, Alexander H. J., additional, Crane, Charles F., additional, Hane, James K., additional, Foster, Andrew J., additional, Van der Lee, Theo A. J., additional, Grimwood, Jane, additional, Aerts, Andrea, additional, Antoniw, John, additional, Bailey, Andy, additional, Bluhm, Burt, additional, Bowler, Judith, additional, Bristow, Jim, additional, van der Burgt, Ate, additional, Canto-Canché, Blondy, additional, Churchill, Alice C. L., additional, Conde-Ferràez, Laura, additional, Cools, Hans J., additional, Coutinho, Pedro M., additional, Csukai, Michael, additional, Dehal, Paramvir, additional, De Wit, Pierre, additional, Donzelli, Bruno, additional, van de Geest, Henri C., additional, van Ham, Roeland C. H. J., additional, Hammond-Kosack, Kim E., additional, Henrissat, Bernard, additional, Kilian, Andrzej, additional, Kobayashi, Adilson K., additional, Koopmann, Edda, additional, Kourmpetis, Yiannis, additional, Kuzniar, Arnold, additional, Lindquist, Erika, additional, Lombard, Vincent, additional, Maliepaard, Chris, additional, Martins, Natalia, additional, Mehrabi, Rahim, additional, Nap, Jan P. H., additional, Ponomarenko, Alisa, additional, Rudd, Jason J., additional, Salamov, Asaf, additional, Schmutz, Jeremy, additional, Schouten, Henk J., additional, Shapiro, Harris, additional, Stergiopoulos, Ioannis, additional, Torriani, Stefano F. F., additional, Tu, Hank, additional, de Vries, Ronald P., additional, Waalwijk, Cees, additional, Ware, Sarah B., additional, Wiebenga, Ad, additional, Zwiers, Lute-Harm, additional, Oliver, Richard P., additional, Grigoriev, Igor V., additional, and Kema, Gert H. J., additional
- Published
- 2011
- Full Text
- View/download PDF
16. Horizontal gene and chromosome transfer in plant pathogenic fungi affecting host range
- Author
-
Mehrabi, Rahim, primary, Bahkali, Ali H., additional, Abd-Elsalam, Kamel A., additional, Moslem, Mohamed, additional, Ben M'Barek, Sarrah, additional, Gohari, Amir Mirzadi, additional, Jashni, Mansoor Karimi, additional, Stergiopoulos, Ioannis, additional, Kema, Gert H.J., additional, and de Wit, Pierre J.G.M., additional
- Published
- 2011
- Full Text
- View/download PDF
17. Meiosis Drives Extraordinary Genome Plasticity in the Haploid Fungal Plant Pathogen Mycosphaerella graminicola
- Author
-
Wittenberg, Alexander H. J., primary, van der Lee, Theo A. J., additional, Ben M'Barek, Sarrah, additional, Ware, Sarah B., additional, Goodwin, Stephen B., additional, Kilian, Andrzej, additional, Visser, Richard G. F., additional, Kema, Gert H. J., additional, and Schouten, Henk J., additional
- Published
- 2009
- Full Text
- View/download PDF
18. Tagging pathogenicity genes in Fusarium graminearumusing the transposon system mimp/impala
- Author
-
Dufresne, Marie, Van Der Lee, Theo, Ben M’Barek, Sarrah, Xu, X., Zhang, X., Liu, Taiguo, Zhang, Wenwei, Kema, Gert H. J., Daboussi, Marie-Josée, and Waalwijk, Cees
- Abstract
Transposon mutagenesis was applied to generate mutants in Fusarium graminearum. The mimp1/impalasystem originally identified in F. oxysporumproved very promising for mutagenesis as the transposon and reinserted at high frequency in (the vicinity) of genes. A collection of mutants was screened for growth, for pathogenicity and for perithecia production. Several mutants blocked in one or more functions were obtained. The wild-type phenotype of one such mutant could be restored by complementation with a non-disrupted copy of the gene. In addition reinsertions occurred on each of the four chromosomes of F. graminearum, making this system a powerful tool in the functional analyses of the > 10,000 genes predicted in the F. graminearumgenome.
- Published
- 2008
- Full Text
- View/download PDF
19. Transposition of a Fungal Miniature Inverted-Repeat Transposable Element Through the Action of a Tc1-Like Transposase.
- Author
-
Dufresne, Marie, Aurélie Hua-Van, Hala Abd el Wahab, Ben M'barek, Sarrah, Vasnier, Christelle, Teysset, Laure, Kema, Gert H. J., and Daboussi, Marie-Josée
- Subjects
- *
ASCOMYCETES , *FUSARIUM oxysporum , *HOMOGENEITY , *IMPALA , *NUCLEOTIDES , *FUNGI , *GENOMICS , *MICROFUNGI - Abstract
The mimp1 element previously identified in the ascomycete fungus Fusarium oxysporum has hallmarks of miniature inverted-repeat transposable elements (MITEs): short size, terminal inverted repeats (TIRs), structural homogeneity, and a stable secondary structure. Since mimp1 has no coding capacity, its mobilization requires a transposase-encoding element. On the basis of the similarity of TIRs and target-site preference with the autonomous Tcl-like element impala, together with a correlated distribution of both elements among the Fusarium genus, we investigated the ability of mimp1 to jump upon expression of the impala transposase provided in trans. Under these conditions, we present evidence that mimp1 transposes by a cut-and-paste mechanism into TA dinucleotides, which are duplicated upon insertion. Our results also show that mimp1 reinserts very frequently in genic regions for at least one-third of the cases. We also show that the mimp1/impala double-component system is fully functional in the heterologous species F. graminearum, allowing the development of a highly efficient tool for gene tagging in filamentous fungi. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
- View/download PDF
20. Genome-wide association analysis of tan spot disease resistance in durum wheat accessions from Tunisia.
- Author
-
Laribi M, Fredua-Agyeman R, Ben M'Barek S, Sansaloni CP, Dreisigacker S, Gamba FM, Abdedayem W, Nefzaoui M, Araar C, Hwang SF, Yahyaoui AH, and Strelkov SE
- Abstract
Background: Tunisia harbors a rich collection of unexploited durum wheat landraces ( Triticum durum ssp. durum ) that have been gradually replaced by elite cultivars since the 1970s. These landraces represent an important potential source for broadening the genetic background of elite durum wheat cultivars and for the introgression of novel genes for key traits, including disease resistance, into these cultivars. Methods: In this study, single nucleotide polymorphism (SNP) markers were used to investigate the genetic diversity and population structure of a core collection of 235 durum wheat accessions consisting mainly of landraces. The high phenotypic and genetic diversity of the fungal pathogen Pyrenophora tritici-repentis (cause of tan spot disease of wheat) in Tunisia allowed the assessment of the accessions for tan spot resistance at the adult plant stage under field conditions over three cropping seasons. A genome-wide association study (GWAS) was performed using a 90k SNP array. Results: Bayesian population structure analysis with 9191 polymorphic SNP markers classified the accessions into two groups, where groups 1 and 2 included 49.79% and 31.49% of the accessions, respectively, while the remaining 18.72% were admixtures. Principal coordinate analysis, the unweighted pair group method with arithmetic mean and the neighbor-joining method clustered the accessions into three to five groups. Analysis of molecular variance indicated that 76% of the genetic variation was among individuals and 23% was between individuals. Genome-wide association analyses identified 26 SNPs associated with tan spot resistance and explained between 8.1% to 20.2% of the phenotypic variation. The SNPs were located on chromosomes 1B (1 SNP), 2B (4 SNPs), 3A (2 SNPs), 3B (2 SNPs), 4A (2 SNPs), 4B (1 SNP), 5A (2 SNPs), 5B (4 SNPs), 6A (5 SNPs), 6B (2 SNPs), and 7B (1 SNP). Four markers, one on each of chromosomes 1B, and 5A, and two on 5B, coincided with previously reported SNPs for tan spot resistance, while the remaining SNPs were either novel markers or closely related to previously reported SNPs. Eight durum wheat accessions were identified as possible novel sources of tan spot resistance that could be introgressed into elite cultivars. Conclusion: The results highlighted the significance of chromosomes 2B, 5B, and 6A as genomic regions associated with tan spot resistance., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Laribi, Fredua-Agyeman, Ben M’Barek, Sansaloni, Dreisigacker, Gamba, Abdedayem, Nefzaoui, Araar, Hwang, Yahyaoui and Strelkov.)
- Published
- 2023
- Full Text
- View/download PDF
21. Characterization of Pyrenophora tritici-repentis in Tunisia and Comparison with a Global Pathogen Population.
- Author
-
Laribi M, Akhavan A, Ben M'Barek S, Yahyaoui AH, Strelkov SE, and Sassi K
- Subjects
- Triticum genetics, Tunisia, Ascomycota genetics, Plant Diseases genetics
- Abstract
Pyrenophora tritici-repentis causes tan spot, an important foliar disease of wheat. A collection of P . tritici-repentis isolates from Tunisia, located in one of the main secondary centers of diversification of durum wheat, was tested for phenotypic race classification based on virulence on a host differential set and for the presence of the necrotrophic effector (NE) genes ToxA , ToxB , and toxb by PCR analysis. While races 2, 4, 5, 6, 7, and 8 were identified according to their virulence phenotypes, PCR testing indicated the presence of "atypical" isolates that induced necrosis on the wheat differential 'Glenlea,' but lacked the expected ToxA gene, suggesting the involvement of other NEs in the P . tritici-repentis /wheat interaction. Genetic diversity and the P . tritici-repentis population structure were explored further by examining 59 Tunisian isolates and 35 isolates from Algeria, Azerbaijan, Canada, Iran, and Syria using 24 simple sequence repeat markers. Average genetic diversity, overall gene flow, and percentage polymorphic loci were estimated as 0.58, 2.09, and 87%, respectively. Analysis of molecular variance showed that 81% of the genetic variance occurred within populations and 19% occurred between populations. Cluster analysis by the unweighted pair group method indicated that ToxB
- isolates grouped together and were distantly related to ToxB+ isolates. Based on Nei's analysis, the global collection clustered into two distinct groups according to their region of origin. The results suggest that geographic origin and the host specificity imposed by different NEs can lead to differentiation among P . tritici-repentis populations.- Published
- 2022
- Full Text
- View/download PDF
22. Effector discovery in the fungal wheat pathogen Zymoseptoria tritici.
- Author
-
Mirzadi Gohari A, Ware SB, Wittenberg AH, Mehrabi R, Ben M'Barek S, Verstappen EC, van der Lee TA, Robert O, Schouten HJ, de Wit PP, and Kema GH
- Subjects
- Ascomycota genetics, Ascomycota metabolism, Fungal Proteins genetics, Gene Expression Profiling, Genes, Fungal, Quantitative Trait Loci, Virulence Factors genetics, Ascomycota pathogenicity, Fungal Proteins biosynthesis, Triticum microbiology, Virulence Factors biosynthesis
- Abstract
Fungal plant pathogens, such as Zymoseptoria tritici (formerly known as Mycosphaerella graminicola), secrete repertoires of effectors to facilitate infection or trigger host defence mechanisms. The discovery and functional characterization of effectors provides valuable knowledge that can contribute to the design of new and effective disease management strategies. Here, we combined bioinformatics approaches with expression profiling during pathogenesis to identify candidate effectors of Z. tritici. In addition, a genetic approach was conducted to map quantitative trait loci (QTLs) carrying putative effectors, enabling the validation of both complementary strategies for effector discovery. In planta expression profiling revealed that candidate effectors were up-regulated in successive waves corresponding to consecutive stages of pathogenesis, contrary to candidates identified by QTL mapping that were, overall, expressed at low levels. Functional analyses of two top candidate effectors (SSP15 and SSP18) showed their dispensability for Z. tritici pathogenesis. These analyses reveal that generally adopted criteria, such as protein size, cysteine residues and expression during pathogenesis, may preclude an unbiased effector discovery. Indeed, genetic mapping of genomic regions involved in specificity render alternative effector candidates that do not match the aforementioned criteria, but should nevertheless be considered as promising new leads for effectors that are crucial for the Z. tritici-wheat pathosystem., (© 2015 BSPP AND JOHN WILEY & SONS LTD.)
- Published
- 2015
- Full Text
- View/download PDF
23. G(alpha) and Gbeta proteins regulate the cyclic AMP pathway that is required for development and pathogenicity of the phytopathogen Mycosphaerella graminicola.
- Author
-
Mehrabi R, Ben M'Barek S, van der Lee TA, Waalwijk C, de Wit PJ, and Kema GH
- Subjects
- Ascomycota genetics, Ascomycota pathogenicity, Cell Differentiation genetics, Cell Enlargement, Cell Proliferation, Cyclic AMP genetics, Fungal Proteins genetics, Fungal Proteins isolation & purification, GTP-Binding Protein alpha Subunits genetics, GTP-Binding Protein alpha Subunits isolation & purification, GTP-Binding Protein beta Subunits genetics, GTP-Binding Protein beta Subunits isolation & purification, Gene Expression Regulation, Fungal genetics, Heterotrimeric GTP-Binding Proteins genetics, Heterotrimeric GTP-Binding Proteins isolation & purification, Mutation genetics, Plant Diseases genetics, Plant Diseases microbiology, Signal Transduction genetics, Triticum genetics, Triticum metabolism, Triticum microbiology, Ascomycota growth & development, Cyclic AMP metabolism, Fungal Proteins metabolism, GTP-Binding Protein alpha Subunits metabolism, GTP-Binding Protein beta Subunits metabolism, Heterotrimeric GTP-Binding Proteins metabolism
- Abstract
We identified and functionally characterized genes encoding three Galpha proteins and one Gbeta protein in the dimorphic fungal wheat pathogen Mycosphaerella graminicola, which we designated MgGpa1, MgGpa2, MgGpa3, and MgGpb1, respectively. Sequence comparisons and phylogenetic analyses showed that MgGPA1 and MgGPA3 are most related to the mammalian Galpha(i) and Galpha(s) families, respectively, whereas MgGPA2 is not related to either of these families. On potato dextrose agar (PDA) and in yeast glucose broth (YGB), MgGpa1 mutants produced significantly longer spores than those of the wild type (WT), and these developed into unique fluffy mycelia in the latter medium, indicating that this gene negatively controls filamentation. MgGpa3 mutants showed more pronounced yeast-like growth accompanied with hampered filamentation and secreted a dark-brown pigment into YGB. Germ tubes emerging from spores of MgGpb1 mutants were wavy on water agar and showed a nested type of growth on PDA that was due to hampered filamentation, numerous cell fusions, and increased anastomosis. Intracellular cyclic AMP (cAMP) levels of MgGpb1 and MgGpa3 mutants were decreased, indicating that both genes positively regulate the cAMP pathway, which was confirmed because the WT phenotype was restored by adding cAMP to these mutant cultures. The cAMP levels in MgGpa1 mutants and the WT were not significantly different, suggesting that this gene might be dispensable for cAMP regulation. In planta assays showed that mutants of MgGpa1, MgGpa3, and MgGpb1 are strongly reduced in pathogenicity. We concluded that the heterotrimeric G proteins encoded by MgGpa3 and MgGpb1 regulate the cAMP pathway that is required for development and pathogenicity in M. graminicola.
- Published
- 2009
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.