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Asian soybean rust, caused by Phakopsora pachyrhizi, is one of the world’s most economically damaging agricultural diseases. Despite P. pachyrhizi’s impact, the exceptional size and complexity of its genome prevented generation of an accurate genome assembly. We simultaneously sequenced three P. pachyrhizi genomes uncovering a genome up to 1.25 Gb comprising two haplotypes with a transposable element (TE) content of ~93%. The proliferation of TEs within the genome occurred in several bursts and correlates with the radiation and speciation of the legumes. We present data of clear de-repression of TEs that mirrors expression of virulence-related candidate effectors. We can see a unique expansion in amino acid metabolism for this fungus. Our data shows that TEs play a dominant role in P. pachyrhizi’s genome and have a key impact on various processes such as host range adaptation, stress responses and genetic plasticity of the genome.

(1) Background: Pancreatic cancer (PaCa) is directly related to malnutrition, cachexia and weight loss. Nutritional interventions (NI) are used in addition to standard therapy. The aim of this systematic review is to provide an overview of the types of NI and their effects. (2) Methods: We included RCTs with at least one intervention group receiving an NI and compared them with a control group with no NI, placebo or alternative treatment on cachexia, malnutrition or weight loss in patients with PaCa. Any available literature until 12 August 2021 was searched in the Pubmed and Cochrane databases. RCTs were sorted according to NI (parenteral nutrition, enteral nutrition, dietary supplements and mixed or special forms). (3) Results: Finally, 26 studies with a total of 2720 patients were included. The potential for bias was mostly moderate to high. Parenteral nutrition is associated with a higher incidence of complications. Enteral nutrition is associated with shorter length of stay in hospital, lower rate and development of complications, positive effects on cytokine rates and lower weight loss. Dietary supplements enriched with omega-3 fatty acids lead to higher body weight and lean body mass. (4) Conclusions: Enteral nutrition and dietary supplements with omega-3 fatty acids should be preferred in nutritional therapy of PaCa patients.

To investigate its susceptibility to ergot infection, we inoculated Brachypodium distachyon with Claviceps purpurea and compared the infection symptoms with those on rye (Secale cereale). We showed that, after inoculation of Brachypodium with Claviceps, the same disease symptoms occurred in comparable temporal and spatial patterns to those on rye. The infection rate of Claviceps on this host was reduced compared with rye, but the disease could be surveyed by fungal genomic DNA quantification. Mutants of Claviceps which were virulence attenuated on rye were also affected on Brachypodium. We were able to show that pathogenesis‐related gene expression changed in a typical manner for biotrophic pathogen attack. Our results indicated that the Claviceps–Brachypodium interaction was dependent on salicylic acid, cytokinin and auxin. We consider Brachypodium to be a suitable and useful alternative host; the increased sensitivity compared with rye will be valuable for the identification of infection mechanisms. Future progess in understanding the Claviceps–plant interaction will be facilitated by the use of a well‐characterized model host system.

Pathogen-derived cytokinins (CKs) have been recognized as important virulence factor in several host-pathogen interactions and it was demonstrated multiple times that phytopathogenic fungi form CKs via the tRNA degradation pathway. In contrast to previous studies, the focus of this study is on the second step of CK formation and CK degradation to improve our understanding of the biosynthesis in fungi on the one hand, and to understand CK contribution to the infection process of Claviceps purpurea on the other hand. The ergot fungus Claviceps purpurea is a biotrophic phytopathogen with a broad host range including economically important crops causing harvest intoxication upon infection. Its infection process is restricted to unfertilized ovaries without causing macroscopic defense symptoms. Thus, sophisticated host manipulation strategies are implicated. The cytokinin (CK) plant hormones are known to regulate diverse plant cell processes, and several plant pathogens alter CK levels during infection. C. purpurea synthesizes CKs via two mechanisms, and fungus-derived CKs influence the host-pathogen interaction but not fungus itself. CK deficiency in fungi with impact on virulence has only been achieved to date by deletion of a tRNA-ipt gene that is also involved in a process of translation regulation. To obtain a better understanding of CK biosynthesis and CKs' contribution to the plant-fungus interaction, we applied multiple approaches to generate strains with altered or depleted CK content. The first approach is based on deletion of the two CK phosphoribohydrolase (LOG)-encoding genes, which are believed to be essential for the release of active CKs. Single and double deletion strains were able to produce all types of CKs. Apparently, log gene products are dispensable for the formation of CKs and so alternative activation pathways must be present. The CK biosynthesis pathway remains unaffected in the second approach, because it is based on heterologous overexpression of CK-degrading enzymes from maize (ZmCKX1). Zmckx1 overexpressing C. purpurea strains shows strong CKX activity and drastically reduced CK levels. The strains are impaired in virulence, which reinforces the assumption that fungal-derived CKs are crucial for full virulence. Taken together, this study comprises the first analysis of a log depletion mutant that proved the presence of alternative cytokinin activation pathways in fungi and showed that heterologous CKX expression is a suitable approach for CK level reduction.

Junction-mediating and regulatory protein (JMY) was originally identified as a transcriptional co-factor in the p53-response to DNA damage. Aside from this nuclear function, recent years have uncovered an additional function of JMY, namely in cytoskeleton remodelling and actin assembly. The C-terminus of JMY comprises a canonical VCA-module, the sequence signature of Arp2/3 complex activators. Furthermore, tandem repeats of 3 WH2 (V, or more recently also W) domains render JMY capable of Arp2/3 independent actin assembly. The motility promoting cytoplasmic function of JMY is abrogated upon DNA-damage and nuclear translocation of JMY. To address the precise cellular function of JMY in cellular actin rearrangements, we have searched for potential new interaction partners by mass spectrometry. We identified several candidates and correlated their localization with the subcellular dynamics of JMY. JMY is localized to dynamic vesiculo-tubular structures throughout the cytoplasm, which are decorated with actin and Arp2/3 complex. Moreover, JMY partially colocalizes and interacts with VAP-A, which is involved in vesicle-based transport processes. Finally, overexpression of JMY results in Golgi dispersal by loss from the trans -site and affects VSV-G transport. These analyses, together with biochemical experiments, indicate that JMY drives vesicular trafficking in the trans -Golgi region and at ER-membrane contact sites (MCS), distinct from other Arp2/3 activators involved in vesicle transport processes such as the related WHAMM or WASH.