Biology subjects

van der Heijden, M.

Publications and source records attributed to van der Heijden, M..

4 recordsLinked to original sources

bioRxiv2025

Stretching of the insect mechanoreceptor evokes mechano-electrical transduction in auditory chordotonal neurons

Insects sound and vibration detection including proprioception rely on the scolopidium--a mechanosensory unit enclosing the sensory cilium of chordotonal organ neurons. The cilium, enclosed by a scolopale cell, contains mechanosensitive ion channels with the ciliary tip embedded in a cap. Despite knowledge of the scolopidial structure in multiple insects, the mechanism by which mechanical force elicits transduction remains speculative. We examined scolopidia in the auditory Mullers organ of the desert locust and present a comprehensive three-dimensional (3D) ultrastructure of a scolopidium using Focused Ion Beam Scanning Electron Microscopy (FIB-SEM). Next, we characterised sound-evoked motions of Mullers organ and the scolopidium using Optical Coherence Tomography (OCT) and high-speed light microscopy. Finally, we measured transduction currents via patch clamp electrophysiology during mechanical stimulation of individual scolopidia. By combining ultrastructure, sound-evoked motions, and transduction current recordings, our finding suggests that the scolopidium is activated best by stretch along the ciliary axis.

neuroscience↗

bioRxiv2020

Diversity and asynchrony in soil microbial communities stabilizes ecosystem functioning

Theoretical and empirical advances have revealed the importance of biodiversity for stabilizing ecosystem functions through time. Yet despite the global degradation of soils, how the loss of soil microbial diversity can de-stabilizes ecosystem functioning is unknown. Here we experimentally quantified the contribution diversity and the temporal dynamics in the composition of soil microbial communities to the temporal stability of four key ecosystem functions related to nutrient and carbon cycling. Soil microbial diversity loss reduced the temporal stability of all ecosystem functions and was particularly strong when over 50% of microbial taxa were lost. The stabilizing effect of soil biodiversity was linked to asynchrony among microbial taxa whereby different soil fungi and bacteria were associated with different ecosystem functions at different times. Our results emphasize the need to conserve soil biodiversity in order to ensure the reliable provisioning of multiple ecosystems functions that soils provide to society.

ecology↗

bioRxiv2020

Specific and conserved patterns of microbiota-structuring by maize benzoxazinoids in the field

BackgroundPlants influence their root and rhizosphere microbial communities through the secretion of root exudates. However, how specific classes of root exudate compounds impact the assembly of these root-associated microbiotas is not well understood. Maize roots secrete benzoxazinoids (BXs), a class of indole-derived defense compounds, and thereby impact the assembly of their microbiota. Here, we investigated the broader impacts of BX exudation on root and rhizosphere microbiotas of adult maize plants grown under natural conditions at different field locations in Europe and the US. We examined the microbiotas of BX-producing and multiple BX-defective lines in two genetic backgrounds across three soil types. ResultsOur analysis showed that the secretion of BXs affected community composition of rhizosphere and root microbiota, with the most pronounced effects observed for root fungi. The impact of the two genetic backgrounds was weaker than that of the presence or absence of BXs, suggesting that BX exudation is a key trait by which maize structures its associated microbiota. BX-producing plants were not consistently enriching microbial lineages across the three soil types. Instead, BX exudation consistently depleted Flavobacteriaceae and Comamonadaceae, and enriched various plant pathogenic fungi in the roots. ConclusionsThese findings reveal that BXs have a selective impact on root and rhizosphere microbiota composition across different field locations. Taken together, this study identifies the BX pathway as an interesting breeding target to manipulate plant-microbiome interactions.

plant biology↗

bioRxiv2018

SPECIES-SPECIFIC ROOT MICROBIOTA DYNAMICS IN RESPONSE TO PLANT-AVAILABLE PHOSPHORUS

O_LIPhosphorus (P) is a limiting element for plant growth. Several root microbes, including arbuscular mycorrhizal fungi (AMF), have the capacity to improve plant nutrition and their abundance is known to depend on P fertility. However, how complex root-associated bacterial and fungal communities respond to changes in P availability remains ill-defined.\nC_LIO_LIWe manipulated the availability of soil P in pots and compared the root microbiota of non-mycorrhizal Arabidopsis with mycorrhizal Petunia plants. Root bacteria and fungi were profiled using ribosomal operon gene fragment sequencing, we searched for P sensitive microbes and tested whether a P sensitive core microbiome could be identified.\nC_LIO_LIRoot microbiota composition varied substantially by P availability. A P sensitive core microbiome was not identified as different bacterial and fungal groups responded to low-P conditions in Arabidopsis and Petunia. P sensitive microbes included Mortierellomycotina in Arabidopsis, while these were AMF and their symbiotic endobacteria in Petunia. Of note, their P-dependent root colonization was reliably quantified by sequencing.\nC_LIO_LIThe species-specific root microbiota dynamics suggest that Arabidopsis and Petunia evolved different microbial associations under the selection pressure of low P availability. This implies that the development of microbial products that improve P availability requires the consideration of host-species specificity.\nC_LI

plant biology↗