Biology subjects

Steidele, C. E.

Publications and source records attributed to Steidele, C. E..

8 recordsLinked to original sources

bioRxiv2025

Network Inference Reveals Distinct Transcriptional Regulation in Barley against Drought and Fusarium Head Blight

We analyzed transcriptional networks in barley under single and combined Fusarium head blight (FHB) and drought stress. We applied complementary Weighted Gene Correlation Network Analysis (WGCNA) to identify stress-associated gene co-expression modules and GENIE3 to infer gene regulatory networks (GRNs). Integration of these frameworks revealed strong overlaps between co-expression modules and GRN clusters, highlighting robust regulatory patterns. Key transcription factors (TFs) were identified based on their weighted node degrees, reflecting their connectivity within the network. Independent analysis of paired transcription factor binding sites in promoter regions further supported predicted regulatory interactions. Notably, WRKY TFs emerged as central regulators of FHB response, consistent with their known roles in defense and secondary metabolite biosynthesis, but did not appear in drought-associated contexts. For bHLH or NAC TFs, individual family members steered FHB or drought responses but not both. Our findings demonstrate the power of combining network inference and motif enrichment to identify candidate TFs controlling stress responses, providing a solid foundation for targeted functional validation.

plant biology↗

bioRxiv2025

Transcriptome and hormone regulations shape drought stress-dependent Fusarium Head Blight susceptibility in different barley genotypes

Little is known about regulatory mechanisms that crop plants use to respond to combinations of abiotic and biotic stress. We analysed four barley genotypes under simultaneous Fusarium culmorum infection and drought stress by phenotyping of Fusarium Head Blight (FHB) disease, hormone profiling, and transcriptome analysis. FHB severity was host genotype-dependent, with moderately resistant cultivars Avalon and Barke showing increased FHB under drought, while drought did not further increase FHB severity in highly susceptible Morex and Palmella Blue. Transcriptome analysis revealed largely additive effects of single stresses, with drought-dominated regulation with increasing drought severity at later stages. Co-expression analysis connected abscisic acid and auxin to gene expression modules functionally enriched with stress-specific physiological responses. Stress-response genes, uniformly expressed across genotypes, were linked to pathogen defence, detoxification, and drought adaptation, whereas a cluster of hundreds of moderately Fusarium-responsive genes was limited in up-regulation under combined stress, possibly explaining enhanced FHB severity under drought. A multiple linear regression model accurately predicted combined stress expression from single stress responses, demonstrating modularity of barleys stress regulation under combined drought and Fusarium stress. Graphical AbstractSimplified working model illustrating drought effects on abscisic acid (ABA) levels and susceptibility to Fusarium Head Blight (FHB) of barley, and key processes such as storage and desiccation responses, photosynthesis, cell wall formation, metabolism, and transferase activity. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=117 SRC="FIGDIR/small/689882v1_ufig1.gif" ALT="Figure 1"> View larger version (30K): org.highwire.dtl.DTLVardef@15504adorg.highwire.dtl.DTLVardef@a62498org.highwire.dtl.DTLVardef@1acb1f5org.highwire.dtl.DTLVardef@d78a3b_HPS_FORMAT_FIGEXP M_FIG C_FIG

plant biology↗

bioRxiv2025

Multi-omics of barley Fusarium Head Blight converge on pathogen-triggered biosynthesis of aromatic amino acid derived chemical defense compounds

Fusarium Head Blight (FHB) is a devastating fungal disease of small grain cereals like wheat and barley, causing substantial yield and quality losses each year worldwide. FHB is caused by Fusarium species that produce mycotoxins such as deoxynivalenol (DON) that impairs protein biosynthesis. Although defense responses in barley to Fusarium infection have been described at the transcriptional level, it remains unclear to what extent these responses are translated into functional changes at the protein and metabolite levels. In this study, we employed comprehensive transcriptomics, proteomics, and metabolomics to dissect the defense responses of barley heads during infection with Fusarium culmorum. Our integrated analyses revealed a set of significantly regulated gene-protein pairs linked to biosynthetic pathways that consistently correspond to upregulated defense-related metabolites. These include tryptophan-derived stress metabolites such as tryptamine and serotonin, as well as barley-specific hydroxycinnamylamides, including conjugates from the trypthophan metabolism, hordatines, and their biosynthetic precursors. Integrating data across multiple omics layers identifies the upregulation of aromatic amino acid derived secondary metabolism as the most consistent barley response to FHB infection across diverse barley varieties that share barley-typical type II resistance to fungal spreading in the head rachis.

plant biology↗

bioRxiv2025

Enhancing plant broad-spectrum resistance through engineered pattern recognition receptors

Conventional plant resistance breeding has primarily focused on intracellular immune receptors, while cell-surface pattern recognition receptors (PRRs) have been underexplored due to their comparatively modest contributions to resistance. However, PRRs offer significant untapped potential for crop improvement. In this study, we demonstrate that the Arabidopsis receptor-like protein RLP23, which recognizes molecular patterns from three distinct microbial kingdoms, confers broad-spectrum resistance when introduced into the Solanaceae crop tomato. We also identify the intracellular (IC) domain of RLP23 as crucial for ensuring compatibility and efficacy during heterologous expression. Targeted engineering of the IC domain significantly enhances RLP23 potential utility, enabling transfer of robust resistance against bacterial, fungal, and oomycete pathogens to other plants without compromising yield. We extended this RLP engineering strategy to rice and poplar, highlighting its broad applicability. These findings establish a versatile framework for PRR-based engineering, opening new avenues for sustainable crop protection.

plant biology↗

bioRxiv2023

Barley shows reduced Fusarium Head Blight under drought and modular expression of differential expressed genes under combined stress

Plants often face simultaneous abiotic and biotic stress conditions. However, physiological and transcriptional responses of plants under combined stress situations are little understood. Spring barley is susceptible to Fusarium Head Blight (FHB), which is strongly affected by weather conditions. We therefore studied the potential influence of drought on FHB severity and responses in three differently susceptible spring barley varieties and found strongly reduced FHB severity in susceptible varieties under drought. Quantity of differentially expressed genes (DEGs) and strength of transcriptomic regulation reflected the concentration of physiological stress markers such as abscisic acid or fungal DNA contents. Infection-related gene expression associated rather with susceptibility than resistance. Weighted gene correlation network analysis uncovered 18 modules of co-expressed genes, which reflect the pathogen or drought response in the used varieties. A generally infection-related module contained co-expressed genes for defence, programmed cell death and mycotoxin-detoxification indicating that diverse genotypes use a similar defence strategy towards FHB albeit with different success. Further DEGs showed co-expression in drought or genotype-associated modules correlating with measured phytohormones or the osmolyte proline. The combination of drought stress with infection lead to highest numbers of DEGs and provoked a modular composition of single stress responses rather than a specific transcriptional readout. HighlightCo-expression network analysis reveals association of physiological stress markers and gene expression modules under biotic and abiotic stress

plant biology↗

bioRxiv2022

Convergent evolution of plant pattern recognition receptors sensing cysteine-rich patterns from three microbial kingdoms

The Arabidopsis thaliana receptor-like protein RLP30 contributes to immunity against the fungal pathogen Sclerotinia sclerotiorum. Here we identified the RLP30-ligand as a small cysteine-rich protein (SCP) that occurs in many fungi and oomycetes and is also recognized by the Nicotiana benthamiana RLP RE02. However, RLP30 and RE02 share little sequence similarity and respond to different parts of the native/folded protein. Interestingly, some Brassicaceae other than Arabidopsis also respond to a linear SCP peptide, suggesting that SCP is an eminent immune target that led to the convergent evolution of distinct immune receptors in plants. Surprisingly, RLP30 shows a second ligand specificity for a SCP-nonhomologous protein secreted by bacterial Pseudomonads. RLP30 expression in N. tabacum resulted in lower susceptibility to bacterial, fungal and oomycete pathogens, thus demonstrating that detection of immunogenic patterns by Arabidopsis RLP30 is involved in defense against pathogens from three microbial kingdoms.

plant biology↗

bioRxiv2020

The secreted hypersensitive response inducing protein 1 from Botrytis cinerea displays non-canonical PAMP-activity

According to their lifestyle, plant pathogens are divided into biotrophic and necrotrophic organisms. While biotrophic pathogens establish a relationship with living host cells, necrotrophic pathogens rapidly kill host cells and feed on the cell debris. To this end, the necrotrophic ascomycete fungus Botrytis cinerea secretes large amounts of phytotoxic proteins and cell wall degrading enzymes. However, the precise role of these proteins during the infection process is unknown. Here we report on the identification and characterization of the previously unknown toxic protein hypersensitive response inducing protein 1 (Hip1), which induces plant cell death. We found the adoption of a folded protein structure to be a prerequisite for Hip1 to exert its necrosis-inducing activity in Nicotiana benthamiana. Localization and the induction of specific plant responses by Hip1 indicate recognition as pathogen-associated molecular pattern at the plant plasma membrane. Our results demonstrate that recognition of Hip1, even in the absence of obvious enzymatic or poreforming activity, induces strong plant defense reactions eventually leading to plant cell death.

plant biology↗

bioRxiv2020

Multi-omics approach highlights differences between functional RLP classes in Arabidopsis thaliana

The receptor-like protein (RLP) family is a complex gene family with 57 members in Arabidopsis thaliana. Some members of the RLP family are known to be involved in basal developmental processes, whereas others have found to be involved in defence responses. However, functional data is to date, only available for a small subset of RLPs, leaving the remaining ones classified as RLPs of unknown function. Using publicly available datasets, we annotated those RLPs of unknown functions as either likely defence-related or likely fulfilling a more basal function in plants. Using these categories, we can identify important characteristics that differ between the RLP sub classes. We find the two classes differ in abundance on both transcriptome and proteome level, physical clustering in the genome and putative interaction partners. However, the classes do not differ in the genetic diversity of their individual members in accessible pan-genome data. Our work has several implications for work related to functional studies on RLPs as well as for the understanding of RLP gene family evolution. Using our annotations, we can make suggestions of which RLPs can be identified as potential immune receptors using genetics tools, which can be useful for disease studies. The lack of differences in nucleotide diversity between the two RLP subclasses further suggests that non-synonymous diversity of gene sequences alone cannot distinguish defence from developmental genes. By contrast, differences in transcript and protein abundance or clustering at genomic loci might also allow for functional annotations and characterisation in other plant species.

genomics↗