The emerging vertebrate model species for neurophysiological studies is Danionella cerebrum, new species (Teleostei: Cyprinidae)

Scientific Reports, Journal Year: 2021, Volume and Issue: 11(1)

Published: Sept. 23, 2021

Abstract The four described species of Danionella are tiny, transparent fishes that mature at sizes between 10–15 mm, and represent some the most extreme cases vertebrate progenesis known to date. miniature adult size larval appearance , combined with a diverse behavioral repertoire linked sound production by males, have established as an important model for neurophysiological studies. external similarity different has offered challenge taxonomic identification using traditional characters, leading confusion over identity species. Using morphological molecular approaches, we show here extensively studied is not D. translucida but represents undescribed species, cerebrum n. sp. externally almost identical differs trenchantly in several internal characters. Molecular analyses confirm distinctiveness suggest two even sister taxa. Analysis evolution sexual dimorphisms associated Weberian apparatus reveals significant increases complexity from simpler condition found dracula complex conditions mirifica .

Language: Английский

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Evolutionary divergence of locomotion in two related vertebrate species

Cell Reports, Journal Year: 2022, Volume and Issue: 38(13), P. 110585 - 110585

Published: March 1, 2022

Locomotion exists in diverse forms nature; however, little is known about how closely related species with similar neuronal circuitry can evolve different navigational strategies to explore their environments. Here, we investigate this question by comparing divergent swimming pattern larval Danionella cerebrum (DC) and zebrafish (ZF). We show that DC displays long continuous events when compared the short burst-and-glide ZF. reveal mesencephalic locomotion maintenance neurons midbrain are sufficient cause increased swimming. Moreover, propose availability of dissolved oxygen timing swim bladder inflation drive observed differences pattern. Our findings uncover neural substrate underlying evolutionary divergence its adaptation environmental constraints.

Language: Английский

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Whole-brain optical access in a small adult vertebrate with two- and three-photon microscopy

iScience, Journal Year: 2022, Volume and Issue: 25(10), P. 105191 - 105191

Published: Sept. 23, 2022

Language: Английский

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Development of sound production in Danionella cerebrum

Journal of Experimental Biology, Journal Year: 2024, Volume and Issue: 227(16)

Published: Aug. 15, 2024

ABSTRACT Acoustic signalling, integral to intraspecific communication and reproductive behaviour, undergoes notable changes during an animal's ontogenetic development. The onset progression of this maturation in fish remains poorly understood. Here, we investigated the ontogeny acoustic miniature teleost Danionella cerebrum, one smallest known vertebrates emerging model organism. Its adult males produce audible clicks that appear sequences with a repetition rate ∼60 or ∼120 Hz, caused by consecutive unilateral alternating bilateral compressions swim bladder. To investigate ability, performed long-term sound recordings morphological studies production apparatus D. cerebrum throughout its We found start producing second month their lives continually increase abundance structured over course following 1 2 months. machinery, including specialised bone cartilage structures, starts form after approximately 4 weeks prior reaching sexual maturity. Although amplitude as animals mature, click rates 60 120 Hz are stable This suggests fully mature pattern generation juvenile males, yet continued development drumming capable creating louder sounds.

Language: Английский

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Label‐Free Multiphoton Imaging Reveals Volumetric Shifts Across Development in Sensory‐Related Brain Regions of a Miniature Transparent Vertebrate

The Journal of Comparative Neurology, Journal Year: 2025, Volume and Issue: 533(4)

Published: April 1, 2025

ABSTRACT Animals integrate information from different sensory modalities as they mature and perform increasingly complex behaviors. This may parallel differential investment in specific brain regions depending on the changing demands of inputs. To investigate developmental changes volume canonical regions, we used third harmonic generation imaging for morphometric analysis forebrain midbrain larval through juvenile adult stages Danionella dracula , a transparent, miniature teleost fish whose is optically accessible throughout its lifespan. Relative to whole‐brain volume, increased or telencephalon, higher order integration center, shows most dramatic increases between 30–60 days postfertilization (dpf) again at 90 dpf animals reach adulthood. The torus longitudinalis (TL), visuomotor also significantly 60 dpf. In contrast, optic tectum (TeO), retinal‐recipient target, progressively decreases 30 dpf, whereas relatively consistent across all semicircularis (TS), secondary auditory mechanosensory lateral line olfactory bulb (OB), direct target epithelium. sum, higher‐order centers (telencephalon, TL) occurs juveniles adulthood (60–90 dpf) exhibit more cognitive tasks, modality‐dominant earlier (TeO) development (TS, OB). Complete optical access ’s lifespan provides unique opportunity how structure over correlates with connectivity, microcircuitry, behavior.

Language: Английский

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Label‐free, whole‐brain in vivo mapping in an adult vertebrate with third harmonic generation microscopy

The Journal of Comparative Neurology, Journal Year: 2024, Volume and Issue: 532(4)

Published: April 1, 2024

Abstract Comprehensive understanding of interconnected networks within the brain requires access to high resolution information large field views and over time. Currently, methods that enable mapping structural changes entire in vivo are extremely limited. Third harmonic generation (THG) can resolve myelinated structures, blood vessels, cell bodies throughout without need for any exogenous labeling. Together with deep penetration long wavelengths, this enables brain‐mapping fractions small animals Here, we demonstrate THG microscopy allows non‐invasive label‐free an adult vertebrate, Danionella dracula , which is a miniature species cyprinid fish. We show capability multiple regions particular identification major commissural fiber bundles midbrain hindbrain. These features provide readily discernable landmarks navigation regional‐specific neuronal groups even single neurons during experiments. further how technique easily be coupled fluorescence used as comparative tool studies other similar body such zebrafish ( Danio rerio) tetras Trochilocharax ornatus ). This new evidence, building on previous studies, demonstrates size relative transparency, combined unique capabilities microscopy, vertebrate brain.

Language: Английский

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Evolutionary Dynamics of the OR Gene Repertoire in Teleost Fishes: Evidence of an Association with Changes in Olfactory Epithelium Shape

Molecular Biology and Evolution, Journal Year: 2021, Volume and Issue: 38(9), P. 3742 - 3753

Published: May 4, 2021

Abstract Teleost fishes perceive their environment through a range of sensory modalities, among which olfaction often plays an important role. Richness the olfactory repertoire depends on diversity receptors coded by homologous genes classified into four families: OR, TAAR, VR1, and VR2. Herein, we focus OR gene repertoire. While independent large contractions associated with ecological transitions have been found in mammals, little is known about its evolution teleost fishes, group that includes more than 34,000 living species. We analyzed genomes 163 species representing this group. variation number functional genes, from 15 Broad-nose Pipefish Syngnathus typhle Ocean Sunfish Mola mola, to 429 Zig-zag Eel Mastacembelus armatus. The was higher when multilamellar rosette present. Moreover, lamellae correlated richness slow balanced birth-and-death process generally drives repertoire, inferred several episodes high rates loss, sometimes followed gains genes. These coincide morphological changes organ suggest strong association between morphology

Language: Английский

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Acoustic and postural displays in a miniature and transparent teleost fish,Danionella dracula

Journal of Experimental Biology, Journal Year: 2022, Volume and Issue: 225(16)

Published: Aug. 2, 2022

Acoustic behavior is widespread across vertebrates, including fishes. We report robust acoustic displays during aggressive interactions for a laboratory colony of Danionella dracula, miniature and transparent species teleost fish closely related to zebrafish (Danio rerio), which are hypothesized be sonic based on the presence hypertrophied muscle associated with male swim bladder. Males produce bursts pulsatile sounds distinct postural display - extension lower jaw, morphological trait not present in other but courtship interactions. Females show no evidence sound production or jaw such contexts. Novel pairs size-matched -mismatched males were combined resident-intruder assays where could linked individuals. In both dyad contexts, resident produced significantly more pulses than intruders. During heightened activity, majority highest producers also showed increased extension. Residents extended their intruders Larger size-mismatched dyads extensions compared smaller counterparts, increasing absolute body size. These studies establish D. dracula as that modulates putatively residency size, providing foundation further investigating role multimodal new model clade neurogenomic neuroimaging aggression, social

Language: Английский

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A Model of Discovery: The Role of Imaging Established and Emerging Non-mammalian Models in Neuroscience

Frontiers in Molecular Neuroscience, Journal Year: 2022, Volume and Issue: 15

Published: April 14, 2022

Rodents have been the dominant animal models in neurobiology and neurological disease research over past 60 years. The prevalent use of rats mice neuroscience has driven by several key attributes including their organ physiology being more similar to humans, availability a broad variety behavioral tests genetic tools, widely accessible reagents. However, despite many advances understanding that achieved using rodent models, there remain limitations questions can be addressed these other mammalian models. In particular, vivo imaging mammals at cell-resolution level remains technically difficult demands large investments time cost. simpler nervous systems non-mammalian allow for precise mapping circuits even whole brain with impressive subcellular resolution. types available spans vertebrates non-vertebrates, so an appropriate model most cell biological neurodegenerative likely exists. A push diversify used could help address current gaps knowledge, complement existing rodent-based bodies work, bring new insight into our human disease. Moreover, are inherent aspects such as lifespan tissue transparency make them specifically advantageous studies. Crispr/Cas9 gene editing decreased cost genome sequencing combined optical microscopy enhances utility specific questions. This review seeks synthesize knowledge established emerging organisms cellular-resolution techniques suggest approaches understand neurodegeneration neurobiological processes. We will summarize tools single scale lead increased consideration research.

Language: Английский

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Developmental osteology of Ictalurus punctatus and Noturus gyrinus (Siluriformes: Ictaluridae) with a discussion of siluriform bone homologies

Vertebrate Zoology, Journal Year: 2022, Volume and Issue: 72, P. 661 - 727

Published: Aug. 12, 2022

Abstract The skeleton of Siluriformes is characterized by several autapomorphies, including secondary absence, extreme modification, and purported fusion ossifications. Although well documented in adults, information on skeletal development catfishes relatively sparse typically focused particular regions the (e.g., Weberian apparatus). To further our understanding siluriform skeleton, I document entire two ictalurid species, Ictalurus punctatus (channel catfish) Noturus gyrinus (tadpole madtom) from five days pre-hatch to adult. reexamine homologies bones previously hypothesized represent compound elements as an additional element only known occur some ictalurids. Development complete I. at 22.4 mm SL almost N. (except dorsal- anal-fin distal radials) 14.1 SL. No signs ontogenetic were observed any elements. Previous hypotheses homology these ossifications are reviewed light developmental obtained herein. dermal parietal component present stage so-called parieto-supraoccipital. bone supraoccipital which ossifies lateral centers ossification later fuse, rather than a median center. ‘posttemporo-supracleithrum’ originates single center represents supracleithrum. posttemporal ictalurids many other canal-bearing between supracleithrum pterotic, sometimes identified extrascapular. extrascapular missing catfishes. Ictalurids have above posttemporal, either independently ossifying fragment or neoformation restricted members this family. chondral pectoral girdle that coracoid. scapula Dorsal-fin radial 2 absent foramen dorsal-fin spine formed modifications base fin-ray itself. Unlike loricarioid catfishes, urohyal solely sternohyoideus tendons. anteriormost infraorbital around sensory canal lacrimal. antorbital Finally, compared available for otophysans, cypriniforms Danio rerio Enteromius holotaenia characiform Salminus brasiliensis .

Language: Английский

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