Browse
Submit Data
Databases
API
Help

Dataset Information

32 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Austropuccinia psidii, causing myrtle rust, has a gigabase-sized genome shaped by transposable elements.

ABSTRACT: Austropuccinia psidii, originating in South America, is a globally invasive fungal plant pathogen that causes rust disease on Myrtaceae. Several biotypes are recognized, with the most widely distributed pandemic biotype spreading throughout the Asia-Pacific and Oceania regions over the last decade. Austropuccinia psidii has a broad host range with more than 480 myrtaceous species. Since first detected in Australia in 2010, the pathogen has caused the near extinction of at least three species and negatively affected commercial production of several Myrtaceae. To enable molecular and evolutionary studies into A. psidii pathogenicity, we assembled a highly contiguous genome for the pandemic biotype. With an estimated haploid genome size of just over 1 Gb (gigabases), it is the largest assembled fungal genome to date. The genome has undergone massive expansion via distinct transposable element (TE) bursts. Over 90% of the genome is covered by TEs predominantly belonging to the Gypsy superfamily. These TE bursts have likely been followed by deamination events of methylated cytosines to silence the repetitive elements. This in turn led to the depletion of CpG sites in TEs and a very low overall GC content of 33.8%. Compared to other Pucciniales, the intergenic distances are increased by an order of magnitude indicating a general insertion of TEs between genes. Overall, we show how TEs shaped the genome evolution of A. psidii and provide a greatly needed resource for strategic approaches to combat disease spread.

SUBMITTER: Tobias PA

PROVIDER: S-EPMC8063080 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Impact of Austropuccinia psidii (myrtle rust) on Myrtaceae-rich wet sclerophyll forests in south east Queensland.

Project description:In April 2010, Austropuccinia psidii (formerly Puccinia psidii) was detected for the first time in Australia on the central coast of New South Wales. The fungus spread rapidly along the east coast and can now be found infecting vegetation in a range of native forest ecosystems with disease impacts ranging from minor leaf spots to severe shoot and stem blight and tree dieback. Localised extinction of some plant species has been recorded. In 2014, the impact of A. psidii was observed for the first time in a wet sclerophyll site with a rainforest understory, dominated by species of Myrtaceae, in Tallebudgera Valley, south east Queensland, Australia. This study aimed to determine the impact of A. psidii on individual species and species composition. Here we provide quantitative and qualitative evidence on the significant impact A. psidii has in native ecosystems, on a broader range of species than previously reported. Archirhodomyrtus beckleri, Decaspermum humile, Gossia hillii and Rhodamnia maideniana are in serious decline, with significant increases in tree mortality over the period of our study. This research further highlights the potential of this invasive pathogen to negatively impact native ecosystems and biodiversity.

| S-EPMC5697815 | biostudies-literature

Transcriptome data from three endemic Myrtaceae species from New Caledonia displaying contrasting responses to myrtle rust (Austropuccinia psidii).

Project description:The myrtle rust disease, caused by the fungus Austropuccinia psidii, infects a wide range of host species within the Myrtaceae family worldwide. Since its first report in 2013 in New Caledonia, it was found on various types of native environments where Myrtaceae are the dominant or codominant species, as well as in several commercial nurseries. It is now considered as a significant threat to ecosystems biodiversity and Myrtaceae-related economy. The use of predictive molecular markers for resistance against myrtle rust is currently the most cost-effective and ecological approach to control the disease. Such an approach for neo Caledonian endemic Myrtaceae species was not possible because of the lack of genomic resources. The recent advancement in new generation sequencing technologies accompanied with relevant bioinformatics tools now provide new research opportunity for work in non-model organism at the transcriptomic level. The present study focuses on transcriptome analysis on three Myrtaceae species endemic to New Caledonia (Arillastrum gummiferum, Syzygium longifolium and Tristaniopsis glauca) that display contrasting responses to the pathogen (non-infected vs infected). Differential gene expression (DGE) and variant calling analysis were conducted on each species. We combined a dual approach by using 1) the annotated reference genome of a related Myrtaceae species (Eucalyptus grandis) and 2) a de novo transcriptomes of each species.

| S-EPMC6362868 | biostudies-literature

Both Constitutive and Infection-Responsive Secondary Metabolites Linked to Resistance against Austropuccinia psidii (Myrtle Rust) in Melaleuca quinquenervia.

Project description:Austropuccinia psidii is a fungal plant pathogen that infects species within the Myrtaceae, causing the disease myrtle rust. Myrtle rust is causing declines in populations within natural and managed ecosystems and is expected to result in species extinctions. Despite this, variation in response to A. psidii exist within some species, from complete susceptibility to resistance that prevents or limits infection by the pathogen. Untargeted metabolomics using Ultra Performance Liquid Chromatography with Ion Mobility followed by analysis using MetaboAnalyst 3.0, was used to explore the chemical defence profiles of resistant, hypersensitive and susceptible phenotypes within Melaleuca quinquenervia during the early stages of A. psidii infection. We were able to identify three separate pools of secondary metabolites: (i) metabolites classified structurally as flavonoids that were naturally higher in the leaves of resistant individuals prior to infection, (ii) organoheterocyclic and carbohydrate-related metabolites that varied with the level of host resistance post-infection, and (iii) metabolites from the terpenoid pathways that were responsive to disease progression regardless of resistance phenotype suggesting that these play a minimal role in disease resistance during the early stages of colonization of this species. Based on the classes of these secondary metabolites, our results provide an improved understanding of key pathways that could be linked more generally to rust resistance with particular application within Melaleuca.

| S-EPMC8879604 | biostudies-literature

The Myrtle rust pathogen, Puccinia psidii, discovered in Africa.

Project description:Puccinia psidii, the cause of a disease today commonly referred to as Myrtle rust, is considered a high priority quarantine threat globally. It has a wide host range in the Myrtaceae and it is feared that it may result in significant damage to native ecosystems where these plants occur. The fungus is also of considerable concern to plantation forestry industries that propagate Australian Eucalyptus species. In May 2013, symptoms of a rust disease resembling those of P. psidii were observed on an ornamental Myrtaceous shrub in a garden in South Africa. The fungus was identified based on DNA sequence data of the ITS and 5.8S nrRNA gene regions and here we report, for the first time, the presence of P. psidii in Africa.

| S-EPMC3719202 | biostudies-literature

Revealing the high variability on nonconserved core and mobile elements of Austropuccinia psidii and other rust mitochondrial genomes.

Project description:Mitochondrial genomes are highly conserved in many fungal groups, and they can help characterize the phylogenetic relationships and evolutionary biology of plant pathogenic fungi. Rust fungi are among the most devastating diseases for economically important crops around the world. Here, we report the complete sequence and annotation of the mitochondrial genome of Austropuccinia psidii (syn. Puccinia psidii), the causal agent of myrtle rust. We performed a phylogenomic analysis including the complete mitochondrial sequences from other rust fungi. The genome composed of 93.299 bp has 73 predicted genes, 33 of which encoded nonconserved proteins (ncORFs), representing almost 45% of all predicted genes. A. psidii mtDNA is one of the largest rust mtDNA sequenced to date, most likely due to the abundance of ncORFs. Among them, 33% were within intronic regions of diverse intron groups. Mobile genetic elements invading intron sequences may have played significant roles in size but not shaping of the rust mitochondrial genome structure. The mtDNAs from rust fungi are highly syntenic. Phylogenetic inferences with 14 concatenated mitochondrial proteins encoded by the core genes placed A. psidii according to phylogenetic analysis based on 18S rDNA. Interestingly, cox1, the gene with the greatest number of introns, provided phylogenies not congruent with the core set. For the first time, we identified the proteins encoded by three A. psidii ncORFs using proteomics analyses. Also, the orf208 encoded a transmembrane protein repressed during in vitro morphogenesis. To the best of our knowledge, we presented the first report of a complete mtDNA sequence of a member of the family Sphaerophragmiacea.

| S-EPMC7951889 | biostudies-literature

Transcriptome analysis using RNA sequencing of three endemic Myrtaceae species from New Caledonia displaying contrasting responses to myrtle rust (Austropuccinia psidii)

Project description:This SuperSeries is composed of the SubSeries listed below.

2018-11-08 | GSE106750 | GEO

Transcriptome analysis using RNA sequencing of three endemic Myrtaceae species from New Caledonia displaying contrasting responses to myrtle rust (Austropuccinia psidii) [ARIGU-DENOVO]

Project description:Finding predictive molecular markers for resistance against Myrtle rust may help to identify resistant plants and provide a means of maintaining Myrtaceae production in nursery, especially for ecosystems restoration purposes. Sequence polymorphism involving in differentiate expressed genes are particularly relevant for disease resistance marker design. We sequenced the transcriptomes of resistant and susceptible individuals of three endemic host species: Arillastrum gummiferum, Tristaniopsis glauca and Syzygium longifolium. The rust phenotype of the individuals of each species was defined as "infected" (considered as susceptible) and "healthy" (considered as resistant). We described here a pre-breeding methodology to find disease resistance markers by combining next-generation sequencing, differential gene expression (DGE) and SNP calling. DGE was conducted in parallel using the only one available sequenced Myrtaceae genome (Eucalyptus grandis) and a de novo assembly transcriptome from each species. The edgeR tests if a gene is DE between “infected” individuals versus “healthy” ones. If the fold change log (FC = infected/healthy) is greater than 0, the gene is thus overexpressed in the infected individuals (considered as susceptible).

2018-11-08 | GSE106735 | GEO

Transcriptome analysis using RNA sequencing of three endemic Myrtaceae species from New Caledonia displaying contrasting responses to myrtle rust (Austropuccinia psidii) [SYZLO-EUCGR]

2018-11-08 | GSE106749 | GEO

Transcriptome analysis using RNA sequencing of three endemic Myrtaceae species from New Caledonia displaying contrasting responses to myrtle rust (Austropuccinia psidii) [SYZLO-DENOVO]

2018-11-08 | GSE106747 | GEO

Transcriptome analysis using RNA sequencing of three endemic Myrtaceae species from New Caledonia displaying contrasting responses to myrtle rust (Austropuccinia psidii) [ARIGU-EUCGR]

2018-11-08 | GSE106736 | GEO