Wheat; host-pathogen interactions; Powdery mildew; host specificity; Leaf rust; resistance gene
Hewitt Tim, Müller Marion C., Molnár István, Mascher Martin, Holušová Kateřina, Šimková Hana, Kunz Lukas, Zhang Jianping, Li Jianbo, Bhatt Dhara, Sharma Raghvendra, Schudel Seraina, Yu Guotai, Steuernagel Burkhard, Periyannan Sambasivam, Wulff Brande, Ayliffe Mick, McIntosh Robert, Keller Beat, Lagudah Evans, Zhang Peng (2021), A highly differentiated region of wheat chromosome 7AL encodes a Pm1a immune receptor that recognizes its corresponding AvrPm1a effector from Blumeria graminis, in New Phytologist
, 229(5), 2812-2826.
Kolodziej Markus C., Singla Jyoti, Sánchez-Martín Javier, Zbinden Helen, Šimková Hana, Karafiátová Miroslava, Doležel Jaroslav, Gronnier Julien, Poretti Manuel, Glauser Gaétan, Zhu Wangsheng, Köster Philipp, Zipfel Cyril, Wicker Thomas, Krattinger Simon G., Keller Beat (2021), A membrane-bound ankyrin repeat protein confers race-specific leaf rust disease resistance in wheat, in Nature Communications
, 12(1), 1-12.
Yang Ping, Scheuermann Daniela, Kessel Bettina, Koller Teresa, Greenwood Julian R., Hurni Severine, Herren Gerhard, Zhou Shenghui, Marande William, Wicker Thomas, Krattinger Simon G., Ouzunova Milena, Keller Beat (2021), Alleles of a wall-associated kinase gene account for three of the major northern corn leaf blight resistance loci in maize, in The Plant Journal
, 106(2), 526-535.
Bräunlich Stephanie, Koller Teresa, Glauser Gaétan, Krattinger Simon G., Keller Beat (2021), Expression of the wheat disease resistance gene Lr34 in transgenic barley leads to accumulation of abscisic acid at the leaf tip, in Plant Physiology and Biochemistry
, 166, 950-957.
Müller Marion C., Kunz Lukas, Graf Johannes, Schudel Seraina, Keller Beat (2021), Host Adaptation Through Hybridization: Genome Analysis of Triticale Powdery Mildew Reveals Unique Combination of Lineage-Specific Effectors, in Molecular Plant-Microbe Interactions
, XX(Xx), 1-8.
Manser Beatrice, Koller Teresa, Praz Coraline Rosalie, Roulin Anne C., Zbinden Helen, Arora Sanu, Steuernagel Burkhard, Wulff Brande B.H., Keller Beat, Sánchez-Martín Javier (2021), Identification of specificity-defining amino acids of the wheat immune receptor Pm2 and powdery mildew effector AvrPm2, in The Plant Journal
, 106(4), 993-1007.
Sánchez-Martín Javier, Keller Beat (2021), NLR immune receptors and diverse types of non-NLR proteins control race-specific resistance in Triticeae, in Current Opinion in Plant Biology
, 62, 1-10.
Gaurav Kumar, Arora Sanu, Silva Paula, Sánchez-Martín Javier, Horsnell Richard, Gao Liangliang, Brar Gurcharn S., Widrig Victoria, John Raupp W., Singh Narinder, Wu Shuangye, Kale Sandip M., Chinoy Catherine, Nicholson Paul, Quiroz-Chávez Jesús, Simmonds James, Hayta Sadiye, Smedley Mark A., Harwood Wendy, Pearce Suzannah, Gilbert David, Kangara Ngonidzashe, Gardener Catherine, Forner-Martínez Macarena, Liu Jiaqian, Yu Guotai, Boden Scott A., Pascucci Attilio, Ghosh Sreya, Hafeez Amber N., O'Hara Tom, Waites Joshua, Cheema Jitender, Steuernagel Burkhard, Patpour Mehran, Justesen Annemarie Fejer, Liu Shuyu, Rudd Jackie C., Avni Raz, Sharon Amir, Steiner Barbara, Kirana Rizky Pasthika, Buerstmayr Hermann, Mehrabi Ali A., Nasyrova Firuza Y., Chayut Noam, Matny Oadi, Steffenson Brian J., Sandhu Nitika, Chhuneja Parveen, Lagudah Evans, Elkot Ahmed F., Tyrrell Simon, Bian Xingdong, Davey Robert P., Simonsen Martin, Schauser Leif, Tiwari Vijay K., Randy Kutcher H., Hucl Pierre, Li Aili, Liu Deng Cai, Mao Long, Xu Steven, Brown-Guedira Gina, Faris Justin, Dvorak Jan, Luo Ming Cheng, Krasileva Ksenia, Lux Thomas, Artmeier Susanne, Mayer Klaus F.X., Uauy Cristobal, Mascher Martin, Bentley Alison R., Keller Beat, Poland Jesse, Wulff Brande B.H. (2021), Population genomic analysis of Aegilops tauschii identifies targets for bread wheat improvement, in Nature Biotechnology
Mueller Marion C., Kunz Lukas, Schudel Seraina, Kammerecker Sandrine, Isaksson Jonatan, Wyler Michele, Graf Johannes, Sotiropoulos Alexandros G., Praz Coraline R., Wicker Thomas, Bourras Salim, Keller Beat (2021), Standing genetic variation of the AvrPm17 avirulence gene in powdery mildew limits the effectiveness of an introgressed rye resistance gene in wheat, in bioRxiv
Sánchez-Martín Javier, Widrig Victoria, Herren Gerhard, Wicker Thomas, Zbinden Helen, Gronnier Julien, Spörri Laurin, Praz Coraline R., Heuberger Matthias, Kolodziej Markus C., Isaksson Jonatan, Steuernagel Burkhard, Karafiátová Miroslava, Doležel Jaroslav, Zipfel Cyril, Keller Beat (2021), Wheat Pm4 resistance to powdery mildew is controlled by alternative splice variants encoding chimeric proteins, in Nature Plants
, 7(3), 327-341.
Bourras Salim, Kunz Lukas, Xue Minfeng, Praz Coraline Rosalie, Müller Marion Claudia, Kälin Carol, Schläfli Michael, Ackermann Patrick, Flückiger Simon, Parlange Francis, Menardo Fabrizio, Schaefer Luisa Katharina, Ben-David Roi, Roffler Stefan, Oberhaensli Simone, Widrig Victoria, Lindner Stefan, Isaksson Jonatan, Wicker Thomas, Yu Dazhao, Keller Beat (2019), The AvrPm3-Pm3 effector-NLR interactions control both race-specific resistance and host-specificity of cereal mildews on wheat, in Nature Communications
, 10(1), 1-16.
The focus of our work is on the molecular determinants of resistance interactions between the wheat (Triticum aestivum) host plant and the obligate biotrophic, fungal pathogens powdery mildew (Blumeria graminis, Bgt) and leaf rust. In the last three years, the genomic tools both for wheat and its pathogens (particularly powdery mildew) have been greatly improved, allowing efficient map-based cloning of genes as well as genome-wide association studies (GWAS). The new resources have allowed us to identify the first avirulence as well as avirulence suppressor genes from powdery mildew three years ago (AvrPm3a2f2, SvrPm3). This work on the pathogen side was complemented by the development of more efficient approaches for resistance gene isolation from wheat, e.g. MutChromSeq which was used for the identification of the Pm2 mildew resistance gene. In the last two years we have isolated a number of novel molecular determinants of the race-specific resistance interaction of mildew and wheat. The AvrPm2, AvrPm3b2c2, AvrPm3d and AvrPm17 genes specifically recognized by the immune receptors Pm2, Pm3b, Pm3c, Pm3d and Pm17, respectively, have been identified and found to encode small effector-like proteins. Each of them belongs to a gene family with close relatives that are not recognized by the respective immune receptor. On the host side we have recently isolated genes for two new immune receptors. In wheat, at total of 77 Pm (powdery mildew resistance) genes/alleles have been genetically described at 53 loci. Each of them confers resistance to a specific set of mildew isolates. In the past, we have cloned a number of these genes which encode immune receptors, and we want to understand the immune network of host and pathogen factors contributing to agricultural resistance which is highly diverse and specific, depending on host-genotype and pathogen race. Thus, the overall goal of the first proposal part is to understand the molecular basis of disease resistance specificity in the agriculturally important wheat-mildew pathosystem. This will help to understand the evolution of pathogen adaptation as well as contribute to strategies for improved resistance gene management in plant breeding. We will analyze the interactions at the molecular level in a transient system to identify by mutagenesis the AVR and host protein domains involved in resistance. Furthermore, we will perform domain swaps between active AVR proteins and the highly similar proteins encoded by closely related gene family members which exist for all our cloned AVR genes. Such domain swaps will give further insight into the protein recognition surfaces and the sub-domains involved in the recognition. We will also study these interactions at the biochemical level, using yeast-2-hybrid systems, co-immunoprecipitation experiments, bimolecular fluorescence complementation assays and a split-LUC complementation assay. At the protein structural level, we want to purify some of the AVR proteins for protein structure determination. As these proteins have relatively small sizes of around 100 amino acids, structure determinations should be feasible once crystals are obtained. Structural information will then be combined with functional and biochemical studies. This should result in a detailed mechanistic understanding of the specificity of the interactions. Finally, we will continue our genetic approaches on both the host and the pathogen to identify novel factors involved in the determination of specificity of interactions within one host as well as of adaptation to new host species. Building on ongoing work, we will perform a molecular analysis of wheat Lr34 and maize Htn1 gene functions which are both contributing to quantitative disease resistance against fungal diseases in cereals. We want to study allelic and functional diversity of the maize Htn1 resistance gene and possibly related genes. Furthermore, the durable, quantitatively acting wheat resistance gene Lr34 will be functionally analyzed in heterologous cereal species such as barley, rice and maize for its role in conferring a unique, partial resistance phenotype. The work should also allow us to generate hypotheses on additional components involved in durable pathogen resistance.