All articles tagged with #zebrafish
Researchers have developed a new imaging technique called WHOLISTIC that allows scientists to observe cellular communication across an entire living vertebrate body simultaneously. By using genetically engineered transparent fish, the method captures real-time calcium activity in nearly every cell, revealing previously unknown interactions between organs, muscles, and the brain.
A new platform called WHOLISTIC enables simultaneous, high-resolution imaging of cellular calcium dynamics across nearly the entire body of transparent vertebrates (larval zebrafish and Danionella cerebrum). By combining pan-cellular calcium sensors, fast volumetric microscopy, and whole-body expansion microscopy, the method uncovers cross-tissue activity patterns, organ-level traveling waves, muscle–organ couplings, and brain–body circuits (including brainstem control of blood flow during stress). The study also demonstrates causal links using optogenetics and maps cellular substrates with ExM, offering a scalable framework for systems physiology and disease research across multiple scales.
In larval zebrafish, researchers uncover a hierarchical thalamus–hindbrain circuit where discrete attractor dynamics in the dorsal thalamus maintain the position of the most recent obstacle for 10–20 seconds, creating a categorical memory that biases subsequent choices. A downstream hindbrain integrator combines this history with current sensory cues to produce graded motor outputs, enabling history-biased decisions across multiple trials. Optogenetic perturbations show the dorsal thalamus can either suppress or induce serial bias, while a whole-brain computational model links these attractor dynamics to multi-trial memory via NMDA-mediated processes. The findings propose a general, modular mechanism for history-dependent decision making and demonstrate how persistent history signals can be flexibly integrated with present sensory information.
Yale researchers screened 774 FDA-approved drugs for autism-like traits in genetically modified zebrafish, narrowing to 520 non-toxic candidates; levocarnitine (Carnitor), a cheap prescription drug, stood out by reversing disruptive behaviors and normalizing brain activity in zebrafish with SCN2A and DYRK1A mutations, genes linked to autism. Levocarnitine costs about 44 cents per pill and is approved for carnitine deficiency, but these two mutations are rare in the broader autism population, so benefits would likely apply to a small subset. The work is preclinical, and researchers caution against using levocarnitine to treat autism until human trials are conducted; they also created an open-source drug database to guide future research.
Yale researchers used larval zebrafish to map how 774 FDA-approved drugs affect behaviors tied to autism-risk genes, building an open database of 520 compounds and identifying levocarnitine as a top rescuer for SCN2A and DYRK1A mutations; they validated the effect in human stem-cell–derived neurons, laying groundwork for precision, gene-targeted drug discovery in autism.
Researchers propose that brain cells determine their position not only via chemical signals but also through lineage, with descendants of the same progenitor tending to remain near one another. The lineage-based model of scalable positional information, tested in mouse brains and confirmed in zebrafish, suggests spatial organization can emerge from cell division/migration patterns, complementing chemical cues and potentially informing developmental biology and AI design.
Researchers studying zebrafish embryos found that very large embryonic cells can divide without a fully closed actin contractile ring. Instead, they use a 'mechanical ratchet' system where cytoskeletal fibers and cycles of cytoplasmic stiffness—stabilized by microtubules—drive the contractile band inward step by step across several cell cycles, reshaping textbook views of cytokinesis in large eggs.
Researchers from the Brugués group at TU Dresden report in Nature a new mechanism for early embryonic cell division in yolk-rich cells: a mechanical ratchet that drives division without a fully closed actin contractile ring. By showing microtubule asters stiffen the cytoplasm during interphase and the cytoplasm becomes more fluid in M-phase, they find the actin band can ingress across multiple cell cycles, anchored by microtubules and re-stabilized when the cytoplasm stiffens again. This challenges textbook models and may apply broadly to yolk-rich embryos across species.
A new study using CRISPR technology on zebrafish embryos suggests that the evolution of hands and feet involved repurposing ancient genetic programs, particularly those related to our posterior regions, rather than developing entirely new genes.
Scientists discovered how serotonergic neurons in larval zebrafish process visual feedback related to movement, using a gating mechanism that opens after swimming to help the brain learn which actions lead to successful outcomes, providing insights into neuromodulation and potential implications for understanding mood disorders.
A study published in Science Immunology reveals that exposure to daylight enhances the immune response by regulating the circadian clock in neutrophils, the body's first responders to infection, with potential implications for treating inflammatory conditions.
Israeli scientists have discovered the biological mechanism behind the 'hatching decision' in zebrafish, revealing that a transient brain structure releases a hormone, TRH, to trigger hatching. This hormone, known for thyroid regulation in humans, plays a different role in fish, controlling the timing of hatching based on environmental and developmental cues. The discovery could have implications for improving fish survival rates in aquaculture and understanding similar mechanisms in other species.
New research from Karolinska Institutet and Columbia University reveals that the heart has its own complex nervous system, or "mini-brain," capable of independently regulating the heartbeat. This discovery, made through studies on zebrafish, challenges traditional views and could lead to new treatments for heart diseases like arrhythmias. The study highlights the heart's neural network's complexity and its potential interaction with the brain during stress or disease, offering new therapeutic targets.
Researchers at Weill Cornell Medicine used zebrafish larvae to study how brainstem neurons guide gaze and maintain short-term memory. By mapping neuronal circuits, they developed a computational model that accurately predicted network activity, offering insights into visual-motor systems and potential treatments for eye movement disorders. The study highlights the zebrafish's simple neural anatomy as a valuable model for understanding complex brain functions.
A study on zebrafish reveals that during the first half of sleep, the brain weakens new synaptic connections formed while awake, supporting the Synaptic Homeostasis Hypothesis. This process does not continue into the second half of the night, leaving questions about its purpose. The research highlights the importance of sleep in synaptic pruning, essential for cognitive performance and learning. Further studies are needed to understand the functions of different sleep stages and their impact on brain function.