A5060332490- Plant-Microbe Interactions and Immunity
- Plant pathogens and resistance mechanisms
- Plant Pathogenic Bacteria Studies
- Plant Disease Resistance and Genetics
- Plant Pathogens and Fungal Diseases
- Legume Nitrogen Fixing Symbiosis
- Wheat and Barley Genetics and Pathology
- Peptidase Inhibition and Analysis
- Ubiquitin and proteasome pathways
- Fungal and yeast genetics research
- Biofuel production and bioconversion
- Biochemical and Molecular Research
- Plant Reproductive Biology
- Viral Infectious Diseases and Gene Expression in Insects
- Agricultural Productivity and Crop Improvement
- Food composition and properties
- Yeasts and Rust Fungi Studies
- Sugarcane Cultivation and Processing
- Enzyme Structure and Function
- Mycotoxins in Agriculture and Food
- Growth and nutrition in plants
- Plant Diversity and Evolution
- Phytase and its Applications
- Transgenic Plants and Applications
- Nematode management and characterization studies
Australian National University
2005-2024
University of California, Berkeley
2007-2011
Commonwealth Scientific and Industrial Research Organisation
2004-2007
Plant Industry
2004-2007
Plant resistance proteins (R proteins) recognize corresponding pathogen avirulence (Avr) either indirectly through detection of changes in their host protein targets or direct R-Avr interaction. Although indirect recognition imposes selection against Avr effector function, molecules recognized interaction may overcome sequence diversification rather than loss function. Here we show that the flax rust fungus AvrL567 genes, whose products are by L5, L6, and L7 R flax, highly diverse, with 12...
Abstract Rust fungi, obligate biotrophs that cause disease and yield losses in crops such as cereals soybean (Glycine max), obtain nutrients from the host through haustoria, which are specialized structures develop within cells. Resistance of flax (Linum usitatissimum) to rust (Melampsora lini) involves induction a hypersensitive cell death response at haustoria formation sites, governed by gene-for-gene recognition between resistance pathogen avirulence genes. We identified genes encoding...
The Linum usitatissimum (flax) L gene alleles, which encode nucleotide binding site–Leu rich repeat class intracellular receptor proteins, confer resistance against the Melampsora lini (flax rust) fungus. At least 11 different specificities are known, and corresponding avirulence genes in M. map to eight independent loci, some of complex multiple specificities. We identified an cDNA marker that cosegregates F2 rust family with a locus determining on L5, L6, L7 genes. Two related candidates,...
Abstract Expression of recombinant proteins as fusions to the eukaryotic protein ubiquitin has been found significantly increase yield unstable or poorly expressed proteins. The benefit this technique is further enhanced by availability naturally occurring deubiquitylating enzymes, which remove from fusion product. However, versatility system constrained due lack a robust, easily purified enzyme. Here we report development an efficient expression system, utilizing technique, allows...
Plant resistance proteins provide race-specific immunity through the recognition of pathogen effectors. The genes I, I-2 and I-3 have been incorporated into cultivated tomato (Solanum lycopersicum) from wild species to confer against Fusarium oxysporum f. sp. lycopersici (Fol) races 1, 2 3, respectively. Although Fol effectors corresponding these all identified, only gene has isolated tomato. To isolate gene, we employed a map-based cloning approach used transgenic complementation test...
The tomato I-3 and I-7 genes confer resistance to Fusarium oxysporum f. sp. lycopersici (Fol) race 3 were introgressed into the cultivated tomato, Solanum lycopersicum, from wild relative pennellii. has been identified previously on chromosome 7 encodes an S-receptor-like kinase, but little is known about I-7. Molecular markers have developed for marker-assisted breeding of I-3, none are available We used RNA-seq single nucleotide polymorphism (SNP) analysis approach map a small...
In this article, we describe the presence of genes encoding close homologues an endogenous plant peptide, rapid alkalinization factor (RALF), within genomes 26 species phytopathogenic fungi. Members RALF family are key growth factors in plants, and sequence active region is well conserved between fungal proteins. RALF1-like sequences were observed most cases; however, RALF27-like present Sphaerulina musiva Septoria populicola genomes. These two pathogens poplar and, interestingly, closest...
Summary We have identified the tomato I gene for resistance to Fusarium wilt fungus oxysporum f. sp. lycopersici ( Fol ) and show that it encodes a membrane‐anchored leucine‐rich repeat receptor‐like protein LRR ‐ RLP ). Unlike most other genes involved in plant defence, is not member of cluster contains introns its coding sequence. The loopout domain larger than those s, with distinct composition rich serine threonine residues. also lacks basic cytosolic domain. Instead, this aromatic...
In plant immunity, recognition of pathogen effectors by resistance proteins leads to the activation defenses and a localized cell death response. The AvrM effector from flax rust is small secreted protein that recognized M in flax. Here, we investigate mechanism M-AvrM show these two directly interact yeast two-hybrid assay, this interaction correlates with specificity observed for each different variants. We further characterize demonstrating C-terminal domain required M-dependent death,...
Fungal and oomycete pathogens cause some of the most devastating diseases in crop plants, facilitate infection by delivering a large number effector molecules into plant cell. AvrM is secreted protein from flax rust (Melampsora lini) that can internalize cells absence pathogen, binds to phosphoinositides (PIPs), recognized directly resistance M (Linum usitatissimum), resulting effector-triggered immunity. We determined crystal structures two naturally occurring variants AvrM, AvrM-A avrM,...
Rust fungi are an important group of plant pathogens that cause devastating losses in agricultural, silvicultural and natural ecosystems. Plants can be protected from rust disease by resistance genes encoding receptors trigger a highly effective defence response upon recognition specific pathogen avirulence proteins. Identifying is crucial for understanding how virulence evolves the field. To facilitate gene cloning flax fungus, Melampsora lini, we constructed high-density genetic linkage...
RNA sequencing (RNAseq) reads from cape gooseberry plants (Physalis peruviana) infected with Fusarium oxysporumf. sp. physali (Foph) were mapped against the lineage-specific transcriptome of lycopersici (Fol) to look for putative effector genes. Homologues Fol SIX1(designated SIX1a and SIX1b), SIX7, SIX10, SIX12, SIX15 Ave1were identified. The near identity Foph SIX10 SIX12genes their intergenic regions suggest that this gene cluster may have undergone recent lateral transfer. SIX1bwere...
To infect plants, pathogenic fungi secrete small proteins called effectors. Here, we describe the catalytic activity and potential virulence function of Nudix hydrolase effector AvrM14 from flax rust fungus (Melampsora lini). We completed extensive in vitro assays to characterise enzymatic effector. Additionally, used planta transient expression wild-type catalytically dead versions followed by biochemical assays, phenotypic analysis RNA sequencing unravel how impacts plant immunity. is an...
The effector protein AvrP is secreted by the flax rust fungal pathogen (Melampsora lini) and recognized specifically (Linum usitatissimum) P disease resistance protein, leading to effector-triggered immunity. To investigate biological function of this mechanisms specific recognition we determined crystal structure AvrP. reveals an elongated zinc-finger-like with a novel interleaved zinc-binding topology. residues responsible for zinc binding are conserved in variants mutations these motifs...
Secreted effectors of fungal pathogens are essential elements for disease development. However, lack sequence conservation among identified has long been a problem predicting effector complements in fungi. Here we have explored the expression characteristics avirulence (Avr) genes and candidate flax rust fungus, Melampsora lini. We performed transcriptome sequencing real-time quantitative PCR (qPCR) on RNA extracted from ungerminated spores, germinated isolated haustoria seedlings inoculated...
An understanding of the molecular mechanisms that plant pathogens use to successfully colonise host tissue can be gained by studying biological activity pathogen proteins secreted during infection. Several ‘effector’ with possible roles in virulence have been isolated from extracellular fungal pathogens, including three shown negate defences. In most cases, significant effector variation is observed between different isolates, driven recognitional capacity disease resistance arrayed against...
Abstract Pathogens are able to deliver effector proteins into plant cells enable infection. Some effectors have been found enter subcellular compartments by mimicking host targeting sequences. Although many computational methods exist predict protein localization, they perform poorly for effectors. We introduce LOCALIZER predicting and localization chloroplasts, mitochondria, nuclei. shows greater prediction accuracy chloroplast mitochondrial compared other 652 proteins. For 108 eukaryotic...
Metal-binding sites are ubiquitous in proteins and can be readily utilized for phasing. It is shown that a protein crystal structure solved using single-wavelength anomalous diffraction based on the signal of cobalt ion measured conventional monochromatic X-ray source. The unique absorption edge (1.61 Å) compatible with Cu Kα wavelength (1.54 commonly available macromolecular crystallography laboratories. This approach was applied to determination Melampsora lini avirulence AvrL567-A, novel...
The continued deployment of resistance genes in Australian wheat varieties plays a crucial role the prevention crop losses as result rust infection. Resistance plants act an immune system by recognising specific components pathogen, encoded avirulence (Avr) genes, and initiating defence responses. Recent advances model species, Melampsora lini, which infects cultivated flax (Linum usitatissimum), has led to identification several genes. These encode secreted proteins that are expressed...
Abstract Pathogenic rust fungi constitute a major disease threat to agriculture, but their obligate parasitic lifestyle makes them difficult study. Research on the model flax system has contributed greatly our knowledge of infection and, in particular, mechanisms resistance and susceptibility controlled by (R) genes host avirulence (Avr) pathogen. Twenty R have been isolated encode cytoplasmic proteins with nucleotide-binding domains leucine-rich repeat regions. These act as surveillance for...