Biology subjects

van Krugten, J.

Publications and source records attributed to van Krugten, J..

4 recordsLinked to original sources

bioRxiv2026

Open-source virtual reality platform for head-fixed adult zebrafish

Virtual realities (VRs) are powerful tools to study how brains interact with the world through behavior. We present a new platform for closed-loop high-resolution virtual-reality experiments in head-fixed adult zebrafish. The VR is defined using open-source software, projected onto a semi-hexagonal tank by three projectors, and controlled by software allowing for modular trial-and-block experimental designs. Real time VR updates are performed by an optimized algorithm based on infrared tail videos. Two-photon imaging during behavior is achieved by custom gating of VR projectors and coordinated with stimulus triggers by a microcontroller. Using this system we found that fish respond to visual landmarks in virtual corridors with distinct changes in locomotion parameters and body posture. Adding landmarks to a familiar corridor elicited localized behavioral responses that decayed with experience. Restricting the viewing distance by simulating 'murky water' further confirmed that behavioral responses were driven by the visibility of landmarks independent of their position. Our platform provides a user-friendly, versatile VR system for the joint analysis of neuronal activity and behavior in adult zebrafish

neuroscience↗

bioRxiv2026

Joint experience-dependent representations of odors and temporal context in the zebrafish homolog of piriform cortex

Intelligent behavior requires experience-dependent internal representations of relevant information. We examined representational learning in telencephalic area pDp of adult zebrafish, the homolog of piriform cortex. Activity was measured by multiphoton imaging through a prism in head-fixed fish trained in an odor discrimination task. Population dynamics could be decomposed into independent modes, each consisting of distributed activity across mixed-selectivity neurons, that encoded odor identity, novelty, and the progression of time. Training sharpened novelty detection, strengthened odor-specific response components, and geometrically untangled representational manifolds. Experience-driven plasticity generalized across chemically related stimuli. Main observations could be reproduced phenomenologically by a model assuming linear interactions between novelty-, identity- and time-encoding activity modes. We conclude that pDp jointly represents olfactory and temporal information relevant for episodic memory. Experience enhances the accessibility and generalization of information, indicating that pDp supports brain-wide learning by geometrically organizing olfactory and time-related information on neural manifolds.

neuroscience↗

bioRxiv2022

Differentiated dynamic response in C. elegans chemosensory cilia

Cilia are membrane-enveloped organelles that protrude from the surface of most eurokaryotic cells and play crucial roles in sensing the external environment. For maintenance and function cilia are dependent on intraflagellar transport (IFT). Here we use a combination of microfluidics and fluorescence microscopy to study the response of phasmid chemosensory neurons, in live Caenorhabditis elegans, to chemical stimuli. We found that chemical stimulation resulted in unexpected changes in IFT and ciliary structure. Notably, stimulation with hyperosmotic solutions or chemical repellents resulted in different responses, not only in IFT, ciliary structure and cargo distribution, but also in neuronal activity. The response to chemical repellents results in habituation of the neuronal activity, suggesting that IFT plays a role in regulating the chemosensory response. Our findings show that cilia are able to sense and respond to different external cues in distinct ways, highlighting the flexible nature of cilia as sensing hubs.

biophysics↗

bioRxiv2020

TRPV channel OCR-2 is distributed along C. elegans chemosensory cilia by diffusion in a local interplay with intraflagellar transport

Sensing and reacting to the environment is essential for survival and procreation of most organisms. Caenorhabditis elegans senses soluble chemicals with transmembrane proteins (TPs) in the cilia of its chemosensory neurons. Development, maintenance and function of these cilia relies on intraflagellar transport (IFT), in which motor proteins transport cargo, including sensory TPs, back and forth along the ciliary axoneme. Here we use live fluorescence imaging to show that IFT machinery and the sensory TP OCR-2 reversibly redistribute along the cilium after exposure to repellant chemicals. To elucidate the underlying mechanisms, we performed single-molecule tracking experiments and found that OCR-2 distribution depends on an intricate interplay between IFT-driven transport, normal diffusion and subdiffusion that depends on the specific location in the cilium. These insights in the role of IFT on the dynamics of cellular signal transduction contribute to a deeper understanding of the regulation of sensory TPs and chemosensing.

biophysics↗