Biology subjects

Heinrichs, M.

Publications and source records attributed to Heinrichs, M..

3 recordsLinked to original sources

bioRxiv2025

Dispersal transiently modifies the temperature dependence of ecosystem productivity after an extreme thermal fluctuation

Effects of warming on ecosystem productivity are typically summarized over broad time scales, yet they emerge from communities that can reorganize in a matter of days. Temperature accelerates ecosystem productivity through predictable effects on metabolic rates, but dispersal across thermally heterogeneous metacommunities may modify this effect by redistributing communities and their underlying thermal phenotypes. Using multi-trophic freshwater mesocosm communities in which warming and dispersal were manipulated, we tested the hypothesis that increasing dispersal modifies the thermal sensitivity of gross primary productivity (GPP) through the redistribution of phytoplankton biomass, size spectra, and thermal phenotype composition along spatial thermal gradients. High dispersal temporarily weakened the thermal sensitivity of GPP after an unplanned heatwave. This effect was caused by reduced mass-specific GPP in the warmest mesocosms accompanied by regional homogenization of phytoplankton communities and the spread of poorly adapted thermal phenotypes under the highest dispersal treatments. Except immediately post-heatwave, the thermal sensitivity of GPP was robust to dispersal, despite evidence of metacommunity dynamics. These findings suggest that the temperature dependence of ecosystem metabolism can be briefly modified by dispersal after a perturbation, but remains robust under steady-state conditions.

ecology↗

bioRxiv2021

The Barley HvSTP13GR mutant triggers resistance against biotrophic fungi

High-yielding and stress resistant crops are essential to ensure future food supply. Barley is an important crop to feed livestock and to produce malt, but the annual yield is threatened by pathogen infections. Pathogens can trigger an altered sugar partitioning in the host plant, that possibly leads to an advantage for the pathogen. Hampering these processes represents a promising strategy to potentially increase resistance. We analyzed the response of the barley monosaccharide transporter HvSTP13 towards biotic stress and its potential use for plant protection. The expression of HvSTP13 increased upon bacterial and fungal PAMP application, suggesting a PAMP-triggered signaling that converged on the transcriptional induction of the gene. Promoter studies indicate a region that is likely targeted by transcription factors downstream of PAMP-triggered immunity pathways. We confirmed that the non-functional HvSTP13GR variant confers resistance against an economically relevant biotrophic rust fungus, in barley. In addition, we established targeted CRISPR/Cas9 cytosine base editing in barley protoplasts to generate alternative HvSTP13 mutants and characterized the sugar transport activity and subcellular localization of the proteins. These mutants represent promising variants for future resistance analysis. Our experimental setup provides basal prerequisites to further decode the role of HvSTP13 in response to biological stress. Moreover, in line with other studies, our experiments indicate that the alteration of sugar partitioning pathways, in a host pathogen interaction, is a promising approach to achieve broad and durable resistance in plants.

plant biology↗

bioRxiv2017

Glucocorticoids change neural decoding in the middle cingulate cortex accompanied by a reduction of subjective fear in patients with spider phobia

Glucocorticoids--stress hormones released from the adrenal cortex--reduce phobic fear in anxiety disorders and enhance psychotherapy, possibly by reducing the retrieval of fear memories and enhancing the consolidation of new corrective memories. Glucocorticoid signaling in the basolateral amygdala can influence connected fear and memory-related cortical regions, but this is not fully understood. Previous studies investigated specific pathways moderated by glucocorticoids, for example, visual-temporal pathways; however, these analyses were limited to a-priori selected regions. Here, we performed whole-brain pattern analysis to localize phobic stimulus decoding related to the fear-reducing effect of glucocorticoids. We reanalyzed functional magnetic resonance imaging (fMRI) data from a previously published study with spider-phobic patients and healthy controls. The patients received either glucocorticoids or a placebo treatment before the exposure to spider images. There was moderate evidence that patients with phobia had higher decoding of phobic content in the anterior cingulate cortex (ACC) and the left and right anterior insula compared to controls. Decoding in the ACC and the right insula showed strong evidence for correlation with experienced fear. Patients with cortisol reported a reduction of fear by 10-13%; however, there was only weak evidence for changes in neural decoding compared to placebo which was found in the precuneus, the opercular cortex, and the left cerebellum.

neuroscience↗