Biology subjects

Schafer, P.

Publications and source records attributed to Schafer, P..

4 recordsLinked to original sources

bioRxiv2023

Emergence of synchronised growth oscillations in filamentous fungi

Soil fungi are important decomposers of organic matter and play crucial roles in the biogeochemical cycles in the soil. Many species of fungi grow in the form of branched networks. While there have been investigations on the growth and architecture of the fungal networks, their growth dynamics in space and time is still not fully understood. In this study, we monitor the growth dynamics of the plant-promoting filamentous fungus Serendipita indica for several days in a controlled environment within a microfluidic channel. We find that this species displays synchronized growth oscillations with the onset of sporulation and at a period of 3 hours. Quantifying this experimental synchronisation of oscillatory dynamics, we show that the synchronisation can be captured by the nearest neighbour Kuramoto model. Our analysis suggested the existence of millimetre-scale cell-cell communication across the fungi network. The microfluidic setup presented in this work may aid the future characterization of the molecular mechanisms of the cell-cell communication, which could in turn be exploited in order to control fungi growth and reproductive sporulation in soil and plant health management.

biophysics↗

bioRxiv2019

Cross Trial Meta and Time Series Pharmacodynamic Analyses of Apremilast Effects

Finding biomarkers that provide shared link between disease severity, drug-induced pharmacodynamic effects and response status in human trials can provide number of values for patient benefits: elucidating current therapeutic mechanism-of-action, and, back-translating to fast-track development of next-generation therapeutics. Both opportunities are predicated on proactive generation of human molecular profiles that capture longitudinal trajectories before and after pharmacological intervention. Here, we present the largest plasma proteomic biomarker dataset available to-date and the corresponding analyses from placebo-controlled Phase III clinical trials of the phosphodiesterase type 4 inhibitor apremilast in psoriasis (PSOR), psoriatic arthritis (PsA), and ankylosing spondylitis (AS) from 526 subjects overall. Using approximately 150 plasma analytes tracked across three time points, we identified IL-17A and KLK-7 as biomarkers for disease severity and apremilast pharmacodynamic effect in psoriasis patients. Combined decline rate of KLK-7, PEDF, MDC and ANGPTL4 by Week 16 represented biomarkers for the responder subgroup, shedding insights into therapeutic mechanisms. In ankylosing spondylitis patients, IL-6 and LRG-1 were identified as biomarkers with concordance to disease severity. Apremilast-induced LRG-1 increase was consistent with the overall lack of efficacy in ankylosing spondylitis. Taken together, these findings expanded the mechanistic knowledge base of apremilast and provided translational foundations to accelerate future efforts including compound differentiation, combination, and repurposing.

bioinformatics↗

bioRxiv2018

Discordant perturbations of transcriptome and epigenome landscapes highlight dual roles of proinflammatory players in normal and IL1B-compromised OPC maturation trajectory in a prenatal model of diffuse white matter injury

Inflammatory insults accompanying prematurity provokes diffuse white matter injury (DWMI) which is associated with increased risk of neurodevelopmental disorders: pre-term infants have a 10 to 18-fold increased risk of developing autism spectrum disorders, compared to term infants. DWMI is due to maturation arrest in oligodendrocyte precursor cells (OPCs). Using integrated genome-wide approaches in a validated mouse perinatal model of DWMI, induced by systemic- and neuro-inflammation based on repeated interleukin-1B administrations, we show that neuroinflammation induces limited epigenomic disturbances in OPCs. In contrast, we unravel marked transcriptomic alterations of genes of the immune/inflammatory pathways, which are expressed in unstressed OPCs and physiologically downregulated along OPC maturation. Consistently, we observe that transcription factors of the inflammatory pathways occupy DNA both in unstressed and inflamed OPCs. Thus, rather than altering genome-wide chromatin accessibility, neuroinflammation takes advantage of open chromatin regions and deeply counteracts the stage-dependent downregulation of these active transcriptional programs. Therefore, our study opens new avenues for the future development of targeted approaches to protect preterm brains. Highlights{circ} Limited epigenomic impact of inflammation on OPC maturation blockade {circ}Major transcriptomic disturbances take advantage of a primed epigenetic landscape {circ}Proinflammatory genes are active in OPCs and downregulated upon maturation {circ}Neuroinflammation counteracts both this downregulation and maturation in OPCs

developmental biology↗

bioRxiv2018

Cell type identity determines transcriptomic immune responses in Arabidopsis thaliana roots.

Root pathogens are a major threat in global crop production and protection strategies are required to sustainably enhance the efficiency of root immunity. Our understanding of root immunity is still limited relative to our knowledge of immune responses in leaves. In an effort to reveal the organisation of immunity in roots, we undertook a cell type-specific transcriptome analysis to identify gene networks activated in epidermis, cortex and pericycle cells of Arabidopsis roots upon treatment with two immunity elicitors, the bacterial microbe-associated molecular pattern flagellin, and the endogenous damage-associated molecular pattern Pep1. Our analyses revealed that both elicitors induced immunity gene networks in a cell type-specific manner. Interestingly, both elicitors did not alter cell identity-determining gene networks. Using sophisticated paired motif promoter analyses, we identified key transcription factor pairs involved in the regulation of cell type-specific immunity networks. In addition, our data show that cell identity networks integrate with cell immunity networks to activate cell type-specific immune response according to the functional capabilities of each cell type.\n\nMaterial Distribution FootnoteThe author responsible for distribution of materials integral to the findings presented in this article in accordance with the policy described in the Instructions for Authors (www.plantcell.org) is: Patrick Schafer (p.schafer@warwick.ac.uk).

plant biology↗