Live imaging of excitable axonal microdomains in ankyrin-G-GFP mice.

The axon initial segment (AIS) constitutes not only the site of action potential initiation, but also a hub for activity-dependent modulation of output generation. Recent studies shedding light on AIS function used predominantly post-hoc approaches since no robust murine live reporters exist. Here, we introduce a reporter line in which the AIS is intrinsically labeled by an ankyrin-G-GFP fusion protein activated by Cre recombinase, tagging the native gene.

Diverse maturity-dependent and complementary anti-apoptotic brakes safeguard human iPSC-derived neurons from cell death.

In humans, most neurons are born during embryonic development and have to persist throughout the entire lifespan of an individual. Thus, human neurons have to develop elaborate survival strategies to protect against accidental cell death. We set out to decipher the developmental adaptations resulting in neuronal resilience.

Dendritic axon origin enables information gating by perisomatic inhibition in pyramidal neurons.

Information processing in neuronal networks involves the recruitment of selected neurons into coordinated spatiotemporal activity patterns. This sparse activation results from widespread synaptic inhibition in conjunction with neuron-specific synaptic excitation. We report the selective recruitment of hippocampal pyramidal cells into patterned network activity.

Neocortical pyramidal neurons with axons emerging from dendrites are frequent in non-primates, but rare in monkey and human.

The canonical view of neuronal function is that inputs are received by dendrites and somata, become integrated in the somatodendritic compartment and upon reaching a sufficient threshold, generate axonal output with axons emerging from the cell body. The latter is not necessarily the case. Instead, axons may originate from dendrites.

Sensory input drives rapid homeostatic scaling of the axon initial segment in mouse barrel cortex.

The axon initial segment (AIS) is a critical microdomain for action potential initiation and implicated in the regulation of neuronal excitability during activity-dependent plasticity. While structural AIS plasticity has been suggested to fine-tune neuronal activity when network states change, whether it acts in vivo as a homeostatic regulatory mechanism in behaviorally relevant contexts remains poorly understood. Using the mouse whisker-to-barrel pathway as a model system in combination with immunofluorescence, confocal analysis and electrophysiological recordings, we observed bidirectional AIS plasticity in cortical pyramidal neurons.

Synchronicity of excitatory inputs drives hippocampal networks to distinct oscillatory patterns.

The rodent hippocampus expresses a variety of neuronal network oscillations depending on the behavioral state of the animal. Locomotion and active exploration are accompanied by theta-nested gamma oscillations while resting states and slow-wave sleep are dominated by intermittent sharp wave-ripple complexes. It is believed that gamma rhythms create a framework for efficient acquisition of information whereas sharp wave-ripples are thought to be involved in consolidation and retrieval of memory.

Effects of sublethal doses of thiacloprid and its formulation Calypso on the learning and memory performance of honey bees.

Learning and memory play a central role in the behavior and communication of foraging bees. We have previously shown that chronic uptake of the neonicotinoid thiacloprid affects the behavior of honey bees in the field. Foraging behavior, homing success, navigation performance and social communication were impaired.

Comparative analysis of 3D culture methods on human HepG2 cells.

Human primary hepatocytes represent a gold standard in in vitro liver research. Due to their low availability and high costs alternative liver cell models with comparable morphological and biochemical characteristics have come into focus. The human hepatocarcinoma cell line HepG2 is often used as a liver model for toxicity studies.

Salutogenesis, globalization, and communication.

Achieving successful communication in transcultural contexts means integrating emotional communication patterns into a global context. Professional, rational communication is characteristic of the cultural dimension, and emotions are characteristic of the direct, interpersonal dimension of human existence. Humans strive to achieve coherence in all dimensions of their lives; this goal is in the end the most essential aspect of psychophysical self-regulation.