Unser 10. Leibniz Plant Biochemistry Symposium am 7. und 8. Mai war ein großer Erfolg. Thematisch ging es in diesem Jahr um neue Methoden und Forschungsansätze der Naturstoffchemie. Die exzellenten Vorträge über Wirkstoffe…
Omanische Heilpflanze im Fokus der Phytochemie IPB-Wissenschaftler und Partner aus Dhofar haben jüngst die omanische Heilpflanze Terminalia dhofarica unter die phytochemische Lupe genommen. Die Pflanze ist reich an…
Geschmack ist vorhersagbar: Mit FlavorMiner. FlavorMiner heißt das Tool, das IPB-Chemiker und Partner aus Kolumbien jüngst entwickelt haben. Das Programm kann, basierend auf maschinellem Lernen (KI), anhand der…
Plant immunity is a multilayered process that includes recognition of patterns or effectors from pathogens to elicit defense responses. These include the induction of a cocktail of defense metabolites that typically restrict pathogen virulence. Here, we investigate the interaction between barley roots and the fungal pathogens Bipolaris sorokiniana (Bs) and Fusarium graminearum (Fg) at the metabolite level. We identify hordedanes, a previously undescribed set of labdane-related diterpenoids with antimicrobial properties, as critical players in these interactions. Infection of barley roots by Bs and Fg elicits hordedane synthesis from a 600-kb gene cluster. Heterologous reconstruction of the biosynthesis pathway in yeast and Nicotiana benthamiana produced several hordedanes, including one of the most functionally decorated products 19-b-hydroxy-hordetrienoic acid (19-OH-HTA). Barley mutants in the diterpene synthase genes of this cluster are unable to produce hordedanes but, unexpectedly, show reduced Bs colonization. By contrast, colonization by Fusarium graminearum, another fungal pathogen of barley and wheat, is 4-fold higher in the mutants completely lacking hordedanes. Accordingly, 19-OH-HTA enhances both germination and growth of Bs, whereas it inhibits other pathogenic fungi, including Fg. Analysis of microscopy and transcriptomics data suggest that hordedanes delay the necrotrophic phase of Bs. Taken together, these results show that adapted pathogens such as Bs can subvert plant metabolic defenses to facilitate root colonization.
Publikation
Klein, J.; Lam, H.; Mak, T. D.; Bittremieux, W.; Perez-Riverol, Y.; Gabriels, R.; Shofstahl, J.; Hecht, H.; Binz, P.-A.; Kawano, S.; Van Den Bossche, T.; Carver, J.; Neely, B. A.; Mendoza, L.; Suomi, T.; Claeys, T.; Payne, T.; Schulte, D.; Sun, Z.; Hoffmann, N.; Zhu, Y.; Neumann, S.; Jones, A. R.; Bandeira, N.; Vizcaíno, J. A.; Deutsch, E. W.;The Proteomics Standards Initiative Standardized Formats for Spectral Libraries and Fragment Ion Peak Annotations: mzSpecLib and mzPAFAnal. Chem.9618491-18501(2024)DOI: 10.1021/acs.analchem.4c04091
Mass spectral libraries are collections of reference spectra, usually associated with specific analytes from which the spectra were generated, that are used for further downstream analysis of new spectra. There are many different formats used for encoding spectral libraries, but none have undergone a standardization process to ensure broad applicability to many applications. As part of the Human Proteome Organization Proteomics Standards Initiative (PSI), we have developed a standardized format for encoding spectral libraries, called mzSpecLib (https://psidev.info/mzSpecLib). It is primarily a data model that flexibly encodes metadata about the library entries using the extensible PSI-MS controlled vocabulary and can be encoded in and converted between different serialization formats. We have also developed a standardized data model and serialization for fragment ion peak annotations, called mzPAF (https://psidev.info/mzPAF). It is defined as a separate standard, since it may be used for other applications besides spectral libraries. The mzSpecLib and mzPAF standards are compatible with existing PSI standards such as ProForma 2.0 and the Universal Spectrum Identifier. The mzSpecLib and mzPAF standards have been primarily defined for peptides in proteomics applications with basic small molecule support. They could be extended in the future to other fields that need to encode spectral libraries for nonpeptidic analytes.
Publikation
Wasternack, C.; Hause, B.;BFP1: One of 700 Arabidopsis F-box proteins mediates degradation of JA oxidases to promote plant immunityMol. Plant17375-376(2024)DOI: 10.1016/j.molp.2024.02.008
In plants and mammals, non-homologous end-joining is the dominant pathway to repair DNA double strand breaks, making it challenging to generate knock-in events. We identified two groups of exonucleases from the Herpes Virus and the bacteriophage T7 families that conferred an up to 38-fold increase in HDR frequencies when fused to Cas9/Cas12a in a Tobacco mosaic virus-based transient assay in Nicotiana benthamiana. We achieved precise and scar-free insertion of several kilobases of DNA both in transient and stable transformation systems. In Arabidopsis thaliana, fusion of Cas9 to a Herpes Virus family exonuclease leads to 10-fold higher frequencies of knock-ins in the first generation of transformants. In addition, we demonstrate stable and heritable knock-ins of in wheat in 1% of the primary transformants. Our results open perspectives for the routine production of heritable knock-in and gene replacement events in plants.