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Biology subjects

Engel, M.

Publications and source records attributed to Engel, M..

4 recordsLinked to original sources

Identity domains in complex behavior: Toward a biology of personality

Personality traits offer considerable insight into the biological basis of individual differences. However, existing approaches toward understanding personality across species rely on subjective criteria and limited sets of behavioral readouts, resulting in noisy and often inconsistent outcomes. Here, we introduce a mathematical framework for studying individual differences along dimensions with maximum consistency and discriminative power. We validate this framework in mice, using data from a system for high-throughput longitudinal monitoring of group-housed mice that yields a variety of readouts from all across an individuals behavioral repertoire. We describe a set of stable traits that capture variability in behavior and gene expression in the brain, allowing for better informed mechanistic investigations into the biology of individual differences.

animal behavior and cognition

How much fear is in anxiety?

The selective breeding for extreme behavior on the elevated plus-maze (EPM) resulted in two mouse lines namely high-anxiety behaving (HAB) and low-anxiety behaving (LAB) mice. Using novel behavioral tests we demonstrate that HAB animals additionally exhibit maladaptive escape behavior and defensive vocalizations, whereas LAB mice show profound deficits in escaping from approaching threats which partially results from sensory deficits. We could relate these behavioral distortions to tonic changes in brain activity within the periaqueductal gray (PAG) in HAB mice and the superior colliculus (SC) in LAB mice, using in vivo manganese-enhanced MRI (MEMRI) followed by pharmacological or chemogenetic interventions. Therefore, midbrain-tectal structures govern the expression of both anxiety-like behavior and defensive responses. Our results challenge the uncritical use of the anthropomorphic terms anxiety or anxiety-like for the description of mouse behavior, as they imply higher cognitive processes, which are not necessarily in place.

neuroscience

MetaMap: An atlas of metatranscriptomic reads in human disease-related RNA-seq data

BackgroundWith the advent of the age of big data in bioinformatics, large volumes of data and high performance computing power enable researchers to perform re-analyses of publicly available datasets at an unprecedented scale. Ever more studies imply the microbiome in both normal human physiology and a wide range of diseases. RNA sequencing technology (RNA-seq) is commonly used to infer global eukaryotic gene expression patterns under defined conditions, including human disease-related contexts, but its generic nature also enables the detection of microbial and viral transcripts.\n\nFindingsWe developed a bioinformatic pipeline to screen existing human RNA-seq datasets for the presence of microbial and viral reads by re-inspecting the non-human-mapping read fraction. We validated this approach by recapitulating outcomes from 6 independent controlled infection experiments of cell line models and comparison with an alternative metatranscriptomic mapping strategy. We then applied the pipeline to close to 150 terabytes of publicly available raw RNA-seq data from >17,000 samples from >400 studies relevant to human disease using state-of-the-art high performance computing systems. The resulting data of this large-scale re-analysis are made available in the presented MetaMap resource.\n\nConclusionsOur results demonstrate that common human RNA-seq data, including those archived in public repositories, might contain valuable information to correlate microbial and viral detection patterns with diverse diseases. The presented MetaMap database thus provides a rich resource for hypothesis generation towards the role of the microbiome in human disease.

bioinformatics

The role of m6A-RNA methylation in stress response regulation

N6-Methyladenosine (m6A) is an abundant internal RNA modification that regulates transcript processing and translation. The regulation of brain m6A by stressful stimuli in vivo and its role in the stress response are currently unknown.\n\nHere, we provide a detailed analysis of the stress-epitranscriptome using m6A-Seq, global and gene-specific m6A measurements. We show that stress exposure and glucocorticoids alter m6A and its regulatory network in a region- and time-specific manner. We demonstrate that depletion of the methyltransferase Mettl3 and the demethylase Fto in adult neurons increases fear memory, and alters the transcriptome response to fear as well as synaptic plasticity. Finally, we report that regulation of m6A is impaired in major depressive disorder patients following glucocorticoid receptor activation.\n\nOur findings indicate that brain m6A represents a novel layer of complexity in gene expression regulation after stress and that dysregulation of the m6A-response may contribute to the pathophysiology of stress-related psychiatric disorders.\n\nHighlightsO_LIm6A RNA methylation in adult mouse brain is regulated by stress\nC_LIO_LIBrain m6A levels are temporally and spatially regulated by stress\nC_LIO_LIMettl3 and Fto-KO alter fear memory, transcriptome response and synaptic plasticity\nC_LIO_LIThe m6A-glucocorticoid-response is impaired in major depressive disorder patients\nC_LI\n\neTOC blurbEngel et al. demonstrate a brain-area-specific and time-dependent role for the mRNA modification, m6A, in stress-response regulation. Manipulating m6A-enzymes alters fear-memory, transcriptome-response and synaptic-plasticity. Altered m6A dynamics in depressed patients suggest an involvement of m6A-modifications in stress-related psychiatric disorders.

neuroscience