scholarly journals Rapid olfactory discrimination learning in adult zebrafish

2018 ◽  
Author(s):  
Iori Namekawa ◽  
Nila R. Moenig ◽  
Rainer W. Friedrich
Keyword(s):  
Model Organism ◽  
Food Delivery ◽  
Olfactory Discrimination ◽  
Surface Sampling ◽  
Adult Zebrafish ◽  
Olfactory Conditioning ◽  
Appetitive Behavior ◽  
Odor Discrimination Task ◽  
Behavioral Parameters ◽  
Different Strains

AbstractThe zebrafish is a model organism to study olfactory information processing but efficient behavioral procedures to analyze olfactory discrimination and memory are lacking. We devised an automated odor discrimination task for adult zebrafish based on olfactory conditioning of feeding behavior. Presentation of a conditioned odor (CS+), but not a neutral odor (CS-), was followed by food delivery at a specific location. Fish developed differential behavioral responses to CS+ and CS- within a few trials even when odors were similar. The behavioral response to the CS+ was complex and included components reminiscent of food search such as increased swimming speed and water surface sampling. Appetitive behavior was therefore quantified by a composite score that combined measurements of multiple behavioral parameters. Discrimination behavior was robust in different strains and learned preferences could overcome innate odor preferences. These results confirm that zebrafish can rapidly learn to make fine odor discriminations. The procedure is efficient and provides novel opportunities to dissect the neural mechanisms underlying olfactory discrimination and memory.

scholarly journals Enzyme-constrained models predict the dynamics of Saccharomyces cerevisiae growth in continuous, batch and fed-batch bioreactors

2021 ◽  
Author(s):  
Sara Moreno-Paz ◽  
Joep Schmitz ◽  
Vitor A.P. Martins dos Santos ◽  
Maria Suarez-Diez
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Model Organism ◽  
Growth Dynamics ◽  
Operational Conditions ◽  
Strain Design ◽  
Balance Analysis ◽  
Different Strains ◽  
Batch Bioreactors ◽  
Constrained Models ◽  
Genome Scale

Genome-scale, constraint-based models (GEM) and their derivatives are commonly used to model and gain insights into microbial metabolism. Often, however, their accuracy and predictive power are limited and enable only approximate designs. To improve their usefulness for strain and bio-process design, we studied here their capacity to accurately predict metabolic changes in response to operational conditions in a bioreactor, as well as intracellular, active reactions. We used flux balance analysis (FBA) and dynamic FBA (dFBA) to predict growth dynamics of the model organism Saccharomyces cerevisiae under different industrially relevant conditions. We compared simulations with the latest developed GEM for this organism (Yeast8) and its enzyme-constrained version (ecYeast8) herein described with experimental data and found that ecYeast8 outperforms Yeast8 in all the simulations. EcYeast8 was able to predict well-known traits of yeast metabolism including the onset of the Crabtree effect, the order of substrate consumption during mixed carbon cultivation and production of a target metabolite. We showed how the combination of ecGEM and dFBA links reactor operation and genetic modifications to flux predictions, enabling the prediction of yields and productivities of different strains and (dynamic) production processes. Additionally, we present flux sampling as a tool to analyze flux predictions of ecGEM, of major importance for strain design applications. We showed that constraining protein availability substantially improves accuracy of the description of the metabolic state of the cell under dynamic conditions. This therefore enables more realistic and faithful designs of industrially relevant cell-based processes and, thus, the usefulness of such models

Morphologic and functional characterization of granulocytes and macrophages in embryonic and adult zebrafish

Blood ◽  
2001 ◽  
Vol 98 (10) ◽  
pp. 3087-3096
Author(s):  
Graham J. Lieschke ◽  
Andrew C. Oates ◽  
Meredith O. Crowhurst ◽  
Alister C. Ward ◽  
Judith E. Layton
Keyword(s):  
Functional Characterization ◽  
Cell Mass ◽  
Myeloid Cells ◽  
Model Organism ◽  
Intermediate Cell ◽  
Adult Zebrafish ◽  
Hematopoietic Organ ◽  
Carbon Particles ◽  
And Function ◽  
A Site

The zebrafish is a useful model organism for developmental and genetic studies. The morphology and function of zebrafish myeloid cells were characterized. Adult zebrafish contain 2 distinct granulocytes, a heterophil and a rarer eosinophil, both of which circulate and are generated in the kidney, the adult hematopoietic organ. Heterophils show strong histochemical myeloperoxidasic activity, although weaker peroxidase activity was observed under some conditions in eosinophils and erythrocytes. Embryonic zebrafish have circulating immature heterophils by 48 hours after fertilization (hpf). A zebrafish myeloperoxidase homologue (myeloid-specificperoxidase; mpx) was isolated. Phylogenetic analysis suggested it represented a gene ancestral to the mammalian myeloperoxidase gene family. It was expressed in adult granulocytes and in embryos from 18 hpf, first diffusely in the axial intermediate cell mass and then discretely in a dispersed cell population. Comparison of hemoglobinized cell distribution,mpx gene expression, and myeloperoxidase histochemistry in wild-type and mutant embryos confirmed that the latter reliably identified a population of myeloid cells. Studies in embryos after tail transection demonstrated that mpx- and peroxidase-expressing cells were mobile and localized to a site of inflammation, indicating functional capability of these embryonic granulocytes. Embryonic macrophages removed carbon particles from the circulation by phagocytosis. Collectively, these observations have demonstrated the early onset of zebrafish granulopoiesis, have proved that granulocytes circulate by 48 hpf, and have demonstrated the functional activity of embryonic granulocytes and macrophages. These observations will facilitate the application of this genetically tractable organism to the study of myelopoiesis.

scholarly journals Adult zebrafish as a model organism for behavioural genetics

2010 ◽  
Vol 11 (1) ◽  
Author(s):  
William Norton ◽  
Laure Bally-Cuif
Keyword(s):  
Model Organism ◽  
Adult Zebrafish ◽  
Behavioural Genetics

Long-Term Exposure to Paraquat Alters Behavioral Parameters and Dopamine Levels in Adult Zebrafish (Danio Rerio)

Zebrafish ◽  
2014 ◽  
Vol 11 (2) ◽  
pp. 142-153 ◽  
Author(s):  
Josiane W. Bortolotto ◽  
Giana P. Cognato ◽  
Raissa R. Christoff ◽  
Laura N. Roesler ◽  
Carlos E. Leite ◽  
...  
Keyword(s):  
Danio Rerio ◽  
Adult Zebrafish ◽  
Behavioral Parameters

scholarly journals An automated feeding system for the African killifish reveals effects of dietary restriction on lifespan and allows scalable assessment of associative learning

2021 ◽  
Author(s):  
Andrew McKay ◽  
Chi-Kuo Hu ◽  
Sharon Chen ◽  
Claire Nicole Bedbrook ◽  
Mike Thielvoldt ◽  
...  
Keyword(s):  
Associative Learning ◽  
Dietary Restriction ◽  
Model Organism ◽  
Video Camera ◽  
Food Delivery ◽  
Automated System ◽  
Model Organisms ◽  
Feeding Time ◽  
Feeding System ◽  
Vertebrate Model

AbstractThe African turquoise killifish is an exciting new vertebrate model for aging studies. A significant challenge for any model organism is control over its diet in space and time. To address this challenge, we created an automated and networked fish feeding system. Our automated feeder is designed to be open-source, easily transferable, and built from widely available components. Compared to manual feeding, our automated system is highly precise and flexible. As a proof-of-concept for the feeding schedule flexibility of these automated feeders, we define a favorable regimen for growth and fertility for the African killifish and a dietary restriction regimen where both feeding time and quantity are reduced. We show that this dietary restriction regimen extends lifespan in males. Moreover, combining our automated feeding system with a video camera, we establish an associative learning assay for the killifish. This learning assay provides an integrative measure of cognitive decline during aging. The ability to precisely control food delivery in the killifish opens new areas to assess lifespan and cognitive behavior dynamics and to screen for dietary interventions and drugs in a high-throughput manner previously impossible with traditional vertebrate model organisms.

scholarly journals Regulation of the pleiotropic drug resistance transcription factors Pdr1 and Pdr3 in yeast

St open ◽  
2021 ◽  
Vol 2 ◽  
pp. 1-17
Author(s):  
Tea Vasiljević ◽  
Markus Proft
Keyword(s):  
Drug Resistance ◽  
Chromatin Immunoprecipitation ◽  
Cell Model ◽  
Degradation Mechanism ◽  
Model Organism ◽  
Protein Detection ◽  
Eukaryotic Cell ◽  
Pleiotropic Drug Resistance ◽  
Treat Ment ◽  
Different Strains

Aim: To understand how transcriptional factors Pdr1 and Pdr3, belonging to the pleiotropic drug resistance system, are activated, and regulated after introducing chemical tox- ins to the cell in the model organism Saccharomyces cere-visiae. Methods: Series of molecular methods were applied using different strains ofS. cerevisiae over-expressing proteins of interest as a eukaryotic cell model. The chemical stress in- troduced to the cell is represented by menadione. Results were obtained performing protein detection and analysis. Additionally, the regulation of the DNA binding of the tran- scriptional activators after stimulation is quantified using chromatin immunoprecipitation, employing epitope-tagged factors and real-time qPCR. Results: Our results indicated higher expression levels of the Pdr1 transcriptional factor, compared to its homolo- gous Pdr3 after treatment with menadione. The yeast-cell defence system was tested against various organic solvents to exclude the possibility of their presence potentially af- fecting the results. The results indicate that Pdr1 is most abundant after 30 minutes from the beginning of the treat- ment, compared with 240 minutes after the treatment when the function of the transcription factor is faded. It appears that Pdr1 binding to the PDR5 and SNQ2 promoters, which are both activated by Pdr1, peaks around the same time, or more precisely after 40 minutes from the start of the treatment. Conclusion: The tendency of Pdr1 reduction after its activa- tion by menadione is detected. One possibility is that Pdr1, after recognizing the xenobiotic menadione, is removed by a degradation mechanism. Given the fact that Pdr1 directly binds the xenobiotic molecule, its destruction might help the cells to remove toxic levels of menadione. It is possible that overexpressing the part of Pdr1 which recognizes me- nadione alone was sufficient to detoxify and hence produce a tolerance towards menadione.

scholarly journals Rapid olfactory discrimination learning in adult zebrafish

2018 ◽  
Vol 236 (11) ◽  
pp. 2959-2969 ◽  
Author(s):  
Iori Namekawa ◽  
Nila R. Moenig ◽  
Rainer W. Friedrich
Keyword(s):  
Discrimination Learning ◽  
Olfactory Discrimination ◽  
Adult Zebrafish

Nickel exposure alters behavioral parameters in larval and adult zebrafish

2018 ◽  
Vol 624 ◽  
pp. 1623-1633 ◽  
Author(s):  
Débora Dreher Nabinger ◽  
Stefani Altenhofen ◽  
Paula Eliete Rodrigues Bitencourt ◽  
Laura Roesler Nery ◽  
Carlos Eduardo Leite ◽  
...  
Keyword(s):  
Adult Zebrafish ◽  
Behavioral Parameters ◽  
Nickel Exposure

An acetylcholinesterase inhibitor, donepezil, increases anxiety and cortisol levels in adult zebrafish

2020 ◽  
Vol 34 (12) ◽  
pp. 1449-1456 ◽  
Author(s):  
Ana CVV Giacomini ◽  
Barbara W Bueno ◽  
Leticia Marcon ◽  
Naiara Scolari ◽  
Rafael Genario ◽  
...  
Keyword(s):  
Acetylcholinesterase Inhibitor ◽  
Model Organism ◽  
Acetylcholinesterase Activity ◽  
Acetylcholinesterase Inhibition ◽  
Whole Body ◽  
The Novel ◽  
Adult Zebrafish ◽  
Tank Test ◽  
Cortisol Levels ◽  
Brain Acetylcholinesterase

Background: A potent acetylcholinesterase inhibitor, donepezil is a cognitive enhancer clinically used to treat neurodegenerative diseases. However, its complete pharmacological profile beyond cognition remains unclear. The zebrafish ( Danio rerio) is rapidly becoming a powerful novel model organism in neuroscience and central nervous system drug screening. Aim: Here, we characterize the effects of 24-h donepezil administration on anxiety-like behavioral and endocrine responses in adult zebrafish. Methods: We evaluated zebrafish anxiety-like behaviors in the novel tank, the light-dark and the shoaling tests, paralleled by assessing brain acetylcholinesterase activity and whole-body cortisol levels. Results: Overall, donepezil dose-dependently decreased zebrafish locomotor activity in the novel tank test and reduced time in light in the light-dark test, likely representing hypolocomotion and anxiety-like behaviors. Donepezil predictably decreased brain acetylcholinesterase activity, also increasing whole-body cortisol levels, thus further linking acetylcholinesterase inhibition to anxiety-like behavioral and endocrine responses. Conclusion: Collectively, these findings suggest negative modulation of zebrafish affective behavior by donepezil, support the key role of cholinergic mechanisms in behavioral regulation in zebrafish, and reinforce the growing utility of zebrafish models for studying complex behavioral processess and their neuroendocrine and neurochemical regulation.

Bisphenol S exposure alters behavioral parameters in adult zebrafish and offspring

2020 ◽  
Vol 741 ◽  
pp. 140448
Author(s):  
Weiwei Wang ◽  
Shaoguo Ru ◽  
Liangliang Wang ◽  
Shuhui Wei ◽  
Jie Zhang ◽  
...  
Keyword(s):  
Adult Zebrafish ◽  
Bisphenol S ◽  
Behavioral Parameters
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