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1.
J Biosci ; 492024.
Artigo em Inglês | MEDLINE | ID: mdl-38726822

RESUMO

Fish of the genus Hypselobarbus (Bleeker 1860) are widely dispersed in the rivers of the Western Ghats in India and endemic to southern Indian peninsular freshwaters. These are small- to medium-sized fishes of the family Cyprinidae. Although fish with deformed bodies or body parts are rare in natural waters, this article deals with four abnormal specimens of Hypselobarbus curmuca (Hamilton 1807) collected from the rivers Tunga, Bhadra, and Kali during 2022. The abnormalities observed in four different individuals are pughead deformity, pelvic fin deformity, pectoral fin deformity, and enlarged scales. The morphological comparison of normal individuals of Hypselobarbus curmuca (Hamilton 1807) with abnormal specimens revealed variation. Using the MT-COI gene, species identity was confirmed and the mean genetic divergence between the normal and abnormal specimens was estimated to be less than 1%.


Assuntos
Cyprinidae , Rios , Animais , Índia/epidemiologia , Cyprinidae/genética , Filogenia , Complexo IV da Cadeia de Transporte de Elétrons/genética , Variação Genética , Nadadeiras de Animais/anatomia & histologia , Nadadeiras de Animais/anormalidades , Proteínas de Peixes/genética
2.
Bioinspir Biomim ; 19(4)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38722377

RESUMO

State-of-the-art morphing materials are either very compliant to achieve large shape changes (flexible metamaterials, compliant mechanisms, hydrogels), or very stiff but with infinitesimal changes in shape that require large actuation forces (metallic or composite panels with piezoelectric actuation). Morphing efficiency and structural stiffness are therefore mutually exclusive properties in current engineering morphing materials, which limits the range of their applicability. Interestingly, natural fish fins do not contain muscles, yet they can morph to large amplitudes with minimal muscular actuation forces from the base while producing large hydrodynamic forces without collapsing. This sophisticated mechanical response has already inspired several synthetic fin rays with various applications. However, most 'synthetic' fin rays have only considered uniform properties and structures along the rays while in natural fin rays, gradients of properties are prominent. In this study, we designed, modeled, fabricated and tested synthetic fin rays with bioinspired gradients of properties. The rays were composed of two hemitrichs made of a stiff polymer, joined by a much softer core region made of elastomeric ligaments. Using combinations of experiments and nonlinear mechanical models, we found that gradients in both the core region and hemitrichs can increase the morphing and stiffening response of individual rays. Introducing a positive gradient of ligament density in the core region (the density of ligament increases towards the tip of the ray) decreased the actuation force required for morphing and increased overall flexural stiffness. Introducing a gradient of property in the hemitrichs, by tapering them, produced morphing deformations that were distributed over long distances along the length of the ray. These new insights on the interplay between material architecture and properties in nonlinear regimes of deformation can improve the designs of morphing structures that combine high morphing efficiency and high stiffness from external forces, with potential applications in aerospace or robotics.


Assuntos
Nadadeiras de Animais , Materiais Biomiméticos , Animais , Nadadeiras de Animais/fisiologia , Nadadeiras de Animais/anatomia & histologia , Fenômenos Biomecânicos , Biomimética/métodos , Peixes/fisiologia , Peixes/anatomia & histologia
3.
Anat Histol Embryol ; 53(3): e13044, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38695121

RESUMO

The vitamin D receptor (VDR) signalling has been implicated in vertebrate limb or fin formation. However, the involvement of VDR signalling in the early stages of limb/fin development remains to be elucidated. In this study, the role of VDR signalling in pectoral fin development was investigated in zebrafish embryos. Knockdown of vdr induced the severe impairment of pectoral fin development. The zebrafish larvae lacking vdr exhibited reduced pectoral fins with no skeletal elements. In situ hybridization revealed depletion of vdr downregulated fibroblast growth factor 24 (fgf24), a marker of early pectoral fin bud mesenchyme, in the presumptive fin field even before fin buds were visible. Moreover, a perturbed expression pattern of bone morphogenetic protein 4 (bmp4), a marker of the pectoral fin fold, was observed in the developing fin buds of zebrafish embryos that lost the vdr function. These findings suggest that VDR signalling is crucial in the early stages of fin development, potentially influencing the process by regulating other signalling molecules such as Fgf24 and Bmp4.


Assuntos
Nadadeiras de Animais , Proteína Morfogenética Óssea 4 , Fatores de Crescimento de Fibroblastos , Receptores de Calcitriol , Proteínas de Peixe-Zebra , Peixe-Zebra , Animais , Peixe-Zebra/genética , Peixe-Zebra/embriologia , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Nadadeiras de Animais/embriologia , Nadadeiras de Animais/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Fatores de Crescimento de Fibroblastos/genética , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Proteína Morfogenética Óssea 4/metabolismo , Proteína Morfogenética Óssea 4/genética , Técnicas de Silenciamento de Genes , Transdução de Sinais , Regulação da Expressão Gênica no Desenvolvimento , Hibridização In Situ
4.
Fish Shellfish Immunol ; 149: 109568, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38636741

RESUMO

Pompano fishes have been widely farmed worldwide. As a representative commercial marine species of the Carangidae family, the golden pompano (Trachinotus blochii) has gained significant popularity in China and worldwide. However, because of rapid growth and high-density aquaculture, the golden pompano has become seriously threatened by various diseases. Cell lines are the most cost-effective resource for in vitro studies and are widely used for physiological and pathological research owing to their accessibility and convenience. In this study, we established a novel immortal cell line, GPF (Golden pompano fin cells). GPF has been passaged over 69 generations for 10 months. The morphology, adhesion and extension processes of GPF were evaluated using light and electron microscopy. GPF cells were passaged every 3 days with L-15 containing 20 % fetal bovine serum (FBS) at 1:3. The optimum conditions for GPF growth were 28 °C and a 20 % FBS concentration. DNA sequencing of 18S rRNA and mitochondrial 16S rRNA confirmed that GPF was derived from the golden pompano. Chromosomal analysis revealed that the number pattern of GPF was 48 chromosomes. Transfection experiments demonstrated that GPF could be utilized to express foreign genes. Furthermore, heavy metals (Cd, Cu, and Fe) exhibited dose-dependent cytotoxicity against GPF. After polyinosinic-polycytidylic acid (poly I:C) treatment, transcription of the retinoic acid-inducible gene I-like receptor (RLR) pathway genes, including mda5, mita, tbk1, irf3, and irf7 increased, inducing the expression of interferon (IFN) and anti-viral proteins in GPF cells. In addition, lipopolysaccharide (LPS) stimulation up-regulated the expression of inflammation-related factors, including myd88, irak1, nfκb, il1ß, il6, and cxcl10 expression. To the best of our knowledge, this is the first study on the immune response signaling pathways of the golden pompano using an established fin cell line. In this study, we describe a preliminary investigation of the GPF cell line immune response to poly I:C and LPS, and provide a more rapid and efficient experimental material for research on marine fish immunology.


Assuntos
Doenças dos Peixes , Animais , Linhagem Celular , Doenças dos Peixes/imunologia , Nadadeiras de Animais/imunologia , Poli I-C/farmacologia , Imunidade Inata , Perciformes/imunologia , Perciformes/genética , Peixes/imunologia
5.
Zebrafish ; 21(2): 149-154, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38621206

RESUMO

Rising in popularity as a model organism in the classroom, zebrafish have numerous characteristics that make them ideal for teaching. In this study, we describe an experiment that helps students better understand the concept of tissue regeneration and the genes that control it. This experiment utilizes a dominant negative transgene for fgfr1 and allows students to observe the consequences of its activation. The first part of the laboratory is hands-on, and includes details of the amputation of caudal fins, heat shocking, general fish care, and visual observations. Over the course of a week, students observed the differences between the activated and unactivated transgene in the zebrafish. The second part was literature based, in which students tried to determine which gene is responsible for inhibiting regeneration. This encouraged students to sharpen their skills of deductive reasoning and critical thinking as they conduct research based on the information they receive about dominant negative receptors and transgenes. Having both a hands-on and critical thinking component in the laboratory helped synthesize the learning goals and allowed students to actively participate.


Assuntos
Proteínas de Peixe-Zebra , Peixe-Zebra , Animais , Peixe-Zebra/fisiologia , Proteínas de Peixe-Zebra/genética , Cauda/fisiologia , Nadadeiras de Animais/fisiologia
6.
Methods Mol Biol ; 2744: 503-514, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38683338

RESUMO

FastFish-ID via Closed-Tube barcoding is a portable platform for rapid and accurate identification of fish species that was conceived at Brandeis University, commercialized at Thermagenix, Inc., and further improved at Ecologenix, LLC (see Chap. 17 in this volume). This chapter focuses on the use of FastFish-ID for (1) identification of intraspecies variants, (2) quantitative use of FastFish-ID to measure the decay of fresh fish, and (3) use of FastFish-ID for the identification of dried and processed shark fins.


Assuntos
Código de Barras de DNA Taxonômico , Peixes , Tubarões , Animais , Código de Barras de DNA Taxonômico/métodos , Nadadeiras de Animais
7.
Bioinspir Biomim ; 19(4)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38626775

RESUMO

Animals have evolved highly effective locomotion capabilities in terrestrial, aerial, and aquatic environments. Over life's history, mass extinctions have wiped out unique animal species with specialized adaptations, leaving paleontologists to reconstruct their locomotion through fossil analysis. Despite advancements, little is known about how extinct megafauna, such as the Ichthyosauria one of the most successful lineages of marine reptiles, utilized their varied morphologies for swimming. Traditional robotics struggle to mimic extinct locomotion effectively, but the emerging soft robotics field offers a promising alternative to overcome this challenge. This paper aims to bridge this gap by studyingMixosauruslocomotion with soft robotics, combining material modeling and biomechanics in physical experimental validation. Combining a soft body with soft pneumatic actuators, the soft robotic platform described in this study investigates the correlation between asymmetrical fins and buoyancy by recreating the pitch torque generated by extinct swimming animals. We performed a comparative analysis of thrust and torque generated byCarthorhyncus,Utatsusaurus,Mixosaurus,Guizhouichthyosaurus, andOphthalmosaurustail fins in a flow tank. Experimental results suggest that the pitch torque on the torso generated by hypocercal fin shapes such as found in model systems ofGuizhouichthyosaurus,MixosaurusandUtatsusaurusproduce distinct ventral body pitch effects able to mitigate the animal's non-neutral buoyancy. This body pitch control effect is particularly pronounced inGuizhouichthyosaurus, which results suggest would have been able to generate high ventral pitch torque on the torso to compensate for its positive buoyancy. By contrast, homocercal fin shapes may not have been conducive for such buoyancy compensation, leaving torso pitch control to pectoral fins, for example. Across the range of the actuation frequencies of the caudal fins tested, resulted in oscillatory modes arising, which in turn can affect the for-aft thrust generated.


Assuntos
Nadadeiras de Animais , Modelos Biológicos , Robótica , Natação , Animais , Natação/fisiologia , Nadadeiras de Animais/fisiologia , Nadadeiras de Animais/anatomia & histologia , Robótica/instrumentação , Fenômenos Biomecânicos , Répteis/fisiologia , Répteis/anatomia & histologia , Fósseis , Simulação por Computador , Biomimética/métodos
8.
Evol Dev ; 26(3): e12478, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38650470

RESUMO

The origin of paired appendages became one of the most important adaptations of vertebrates, allowing them to lead active lifestyles and explore a wide range of ecological niches. The basic form of paired appendages in evolution is the fins of fishes. The problem of paired appendages has attracted the attention of researchers for more than 150 years. During this time, a number of theories have been proposed, mainly based on morphological data, two of which, the Balfour-Thacher-Mivart lateral fold theory and Gegenbaur's gill arch theory, have not lost their relevance. So far, however, none of the proposed ideas has been supported by decisive evidence. The study of the evolutionary history of the appearance and development of paired appendages lies at the intersection of several disciplines and involves the synthesis of paleontological, morphological, embryological, and genetic data. In this review, we attempt to summarize and discuss the results accumulated in these fields and to analyze the theories put forward regarding the prerequisites and mechanisms that gave rise to paired fins and limbs in vertebrates.


Assuntos
Nadadeiras de Animais , Evolução Biológica , Peixes , Animais , Nadadeiras de Animais/anatomia & histologia , Nadadeiras de Animais/crescimento & desenvolvimento , Peixes/anatomia & histologia , Peixes/genética , Peixes/crescimento & desenvolvimento , Peixes/embriologia , Vertebrados/anatomia & histologia , Vertebrados/crescimento & desenvolvimento , Vertebrados/genética
9.
J Morphol ; 285(5): e21698, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38669130

RESUMO

The glycosylation of macromolecules can vary both among tissue structural components and by adverse conditions, potentially providing an alternative marker of stress in organisms. Lectins are proteins that bind carbohydrate moieties and lectin histochemistry is a common method to visualize microstructures in biological specimens and diagnose pathophysiological states in human tissues known to alter glycan profiles. However, this technique is not commonly used to assess broad-spectrum changes in cellular glycosylation in response to environmental stressors. In addition, the binding of various lectins has not been studied in elasmobranchs (sharks, skates, and rays). We surveyed the binding tissue structure specificity of 14 plant-derived lectins, using both immunoblotting and immunofluorescence, in the pectoral fins of neonate little skates (Leucoraja erinacea). Skates were reared under present-day or elevated (+5°C above ambient) temperature regimes and evaluated for lectin binding as an indicator of changing cellular glycosylation and tissue structure. Lectin labeling was highly tissue and microstructure specific. Dot blots revealed no significant changes in lectin binding between temperature regimes. In addition, lectins only detected in the elevated temperature treatment were Canavalia ensiformis lectin (Concanavalin A) in spindle cells of muscle and Ricinus communis agglutinin in muscle capillaries. These results provide a reference for lectin labeling in elasmobranch tissue that may aid future investigations.


Assuntos
Lectinas , Temperatura , Animais , Lectinas/metabolismo , Nadadeiras de Animais , Rajidae , Glicosilação , Animais Recém-Nascidos , Ligação Proteica
10.
Dev Growth Differ ; 66(3): 235-247, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38439516

RESUMO

In this study, we comprehensively searched for fish-specific genes in gnathostomes that contribute to development of the fin, a fish-specific trait. Many previous reports suggested that animal group-specific genes are often important for group-specific traits. Clarifying the roles of fish-specific genes in fin development of gnathostomes, for example, can help elucidate the mechanisms underlying the formation of this trait. We first identified 91 fish-specific genes in gnathostomes by comparing the gene repertoire in 16 fish and 35 tetrapod species. RNA-seq analysis narrowed down the 91 candidates to 33 genes that were expressed in the developing pectoral fin. We analyzed the functions of approximately half of the candidate genes by loss-of-function analysis in zebrafish. We found that some of the fish-specific and fin development-related genes, including fgf24 and and1/and2, play roles in fin development. In particular, the newly identified fish-specific gene qkia is expressed in the developing fin muscle and contributes to muscle morphogenesis in the pectoral fin as well as body trunk. These results indicate that the strategy of identifying animal group-specific genes is functional and useful. The methods applied here could be used in future studies to identify trait-associated genes in other animal groups.


Assuntos
Proteínas de Peixe-Zebra , Peixe-Zebra , Animais , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética , Genômica , Nadadeiras de Animais/fisiologia
11.
PLoS Biol ; 22(3): e3002565, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38527087

RESUMO

K+ channels regulate morphogens to scale adult fins, but little is known about what regulates the channels and how they control morphogen expression. Using the zebrafish pectoral fin bud as a model for early vertebrate fin/limb development, we found that K+ channels also scale this anatomical structure, and we determined how one K+-leak channel, Kcnk5b, integrates into its developmental program. From FLIM measurements of a Förster Resonance Energy Transfer (FRET)-based K+ sensor, we observed coordinated decreases in intracellular K+ levels during bud growth, and overexpression of K+-leak channels in vivo coordinately increased bud proportions. Retinoic acid, which can enhance fin/limb bud growth, decreased K+ in bud tissues and up-regulated regulator of calcineurin (rcan2). rcan2 overexpression increased bud growth and decreased K+, while CRISPR-Cas9 targeting of rcan2 decreased growth and increased K+. We observed similar results in the adult caudal fins. Moreover, CRISPR targeting of Kcnk5b revealed that Rcan2-mediated growth was dependent on the Kcnk5b. We also found that Kcnk5b enhanced depolarization in fin bud cells via Na+ channels and that this enhanced depolarization was required for Kcnk5b-enhanced growth. Lastly, Kcnk5b-induced shha transcription and bud growth required IP3R-mediated Ca2+ release and CaMKK activity. Thus, we provide a mechanism for how retinoic acid via rcan2 can regulate K+-channel activity to scale a vertebrate appendage via intercellular Ca2+ signaling.


Assuntos
Cálcio , Peixe-Zebra , Animais , Peixe-Zebra/genética , Cálcio/metabolismo , Tretinoína , Nadadeiras de Animais/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Regulação da Expressão Gênica no Desenvolvimento
12.
Bioinspir Biomim ; 19(3)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38430560

RESUMO

In animal and robot swimmers of body and caudal fin (BCF) form, hydrodynamic thrust is mainly produced by their caudal fins, the stiffness of which has profound effects on both thrust and efficiency of swimming. Caudal fin stiffness also affects the motor control and resulting swimming gaits that correspond to optimal swimming performance; however, their relationship remains scarcely explored. Here using magnetic, modular, undulatory robots (µBots), we tested the effects of caudal fin stiffness on both forward swimming and turning maneuver. We developed six caudal fins with stiffness of more than three orders of difference. For aµBot equipped with each caudal fin (andµBot absent of caudal fin), we applied reinforcement learning in experiments to optimize the motor control for maximizing forward swimming speed or final heading change. The motor control ofµBot was generated by a central pattern generator for forward swimming or by a series of parameterized square waves for turning maneuver. In forward swimming, the variations in caudal fin stiffness gave rise to three modes of optimized motor frequencies and swimming gaits including no caudal fin (4.6 Hz), stiffness <10-4Pa m4(∼10.6 Hz) and stiffness >10-4Pa m4(∼8.4 Hz). Swimming speed, however, varied independently with the modes of swimming gaits, and reached maximal at stiffness of 0.23 × 10-4Pa m4, with theµBot without caudal fin achieving the lowest speed. In turning maneuver, caudal fin stiffness had considerable effects on the amplitudes of both initial head steering and subsequent recoil, as well as the final heading change. It had relatively minor effect on the turning motor program except for theµBots without caudal fin. Optimized forward swimming and turning maneuver shared an identical caudal fin stiffness and similar patterns of peduncle and caudal fin motion, suggesting simplicity in the form and function relationship inµBot swimming.


Assuntos
Procedimentos Cirúrgicos Robóticos , Robótica , Animais , Natação , Fenômenos Biomecânicos , Fenômenos Físicos , Nadadeiras de Animais
13.
J Fish Biol ; 104(5): 1339-1349, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38316148

RESUMO

The early development of the freshwater fish Rhytiodus microlepis is characterized by the description of external morphological, meristic, and morphometric changes, as well as the growth patterns, thereby establishing a reference for the identification of its larvae and juveniles. Specimens were collected from the Amazon river channel and floodplain. Ninety-seven individuals were analysed with standard length varying between 4.31 and 79.23 mm. Rhytiodus microlepis larvae are altricial, with an elongated and fusiform body, anal opening reaching the middle region of the body, and simple nostrils becoming double and tubular during development. The pigments vary from one to two chromatophores in the dorsal region of the head in pre-flexion and flexion, but later the pigmentation pattern intensifies, transverse bands appear along the body, and a conspicuous spot appears in the basal region of the caudal fin. The total number of myomeres ranges from 49 to 50. During the transition from larval (post-flexion) to the juvenile periods, the most significant anatomical changes occur, such as the presence of all fins and increased body pigmentation. Integrated myomere count and pigmentation pattern are effective for the correct identification of the initial life stages of R. microlepis from the Amazon basin. Our results expand the knowledge about the early life history of Neotropical freshwater fish species.


Assuntos
Caraciformes , Larva , Pigmentação , Rios , Animais , Caraciformes/crescimento & desenvolvimento , Caraciformes/anatomia & histologia , Brasil , Larva/crescimento & desenvolvimento , Larva/anatomia & histologia , Água Doce , Nadadeiras de Animais/anatomia & histologia , Nadadeiras de Animais/crescimento & desenvolvimento
14.
Environ Sci Pollut Res Int ; 31(11): 16928-16939, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38326684

RESUMO

Heat losses in solar stills are high, which has led to a decrease in their thermal efficiency. Also, the production of these devices is limited to the presence of the sun, and their production stops during cloudy hours or at night. To solve these problems, in this experimental study, two cascade solar stills are examined under relatively similar conditions for sustainable freshwater production. One of these solar stills is modified with the phase change material and copper fins, and another one is a conventional cascade solar still without using the phase change material and copper fins. Paraffin was selected as a heat storage material to increase the time of desalination of water by the solar still. In addition, the copper fins are used to increase the conduction heat transfer in phase change material and provide better melting and solidification processes. To prolong the water path along the steps, the serpentine water path was considered. The results showed that at sunset hours, desalination efficiency with phase changing material and fins was increased. At 5 pm, the efficiency of the modified device was increased by 29% (on average) as compared to the conventional solar still without using phase changing material and fins. The rate of water production in conventional solar still in midday was higher compared to the modified solar still. However, in the sunset and night hours, the modified solar still has a higher production rate due to heat released from the thermal storage system.


Assuntos
Cobre , Água , Animais , Água Doce , Nadadeiras de Animais , Asbestos Serpentinas
15.
J Exp Biol ; 227(5)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38390692

RESUMO

Pectoral fins play a crucial role in fish locomotion. Despite fishes living in complex fluid environments that exist in rivers and tidal flows, the role of the pectoral fins in navigating turbulent flows is not well understood. This study investigated the kinematics and muscle activity of pectoral fins in rainbow trout as they held station in the unsteady flows behind a D-section cylinder. We observed two distinct pectoral fin behaviors, one during braking and the other during Kármán gaiting. These behaviors were correlated to whole-body movements in response to the hydrodynamic conditions of specific regions in the cylinder wake. Sustained fin extensions during braking, where the fin was held out to maintain its position away from the body and against the flow, were associated with the cessation of forward body velocity, where the fish avoided the suction region directly downstream of the cylinder. Transient fin extensions and retractions during Kármán gaiting controlled body movements in the cross-stream direction. These two fin behaviors had different patterns of muscle activity. All braking events required recruitment from both the abductor and adductor musculature to actively extend a pectoral fin. In contrast, over 50% of fin extension movements during Kármán gaiting proceed in the absence of muscle activity. We reveal that in unsteady fluid environments, pectoral fin movements are the result of a complex combination of passive and active mechanisms that deviate substantially from canonical labriform locomotion, the implications of which await further work on the integration of sensory and motor systems.


Assuntos
Oncorhynchus mykiss , Animais , Oncorhynchus mykiss/fisiologia , Natação/fisiologia , Nadadeiras de Animais , Fenômenos Biomecânicos , Músculo Esquelético
16.
PLoS One ; 19(2): e0298170, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38358968

RESUMO

Bryconops Kner, 1858, includes two well defined subgenera based on morphological evidence, with each containing at least one species (B. (Bryconops) caudomaculatus and B. (Creatochanes) melanurus) with a very wide distribution, within which regional populations present color variations. To test if phenotypic variation is related to cladogenetic events, we performed tests for phylogenetic independence and determined the strength of convergence for color characters in relation to water type, as the variation between clear, black and white waters is considered to be one of the major driving forces in the evolution of Amazonian fishes. Color characters for fins above the median line of the body were generally found to be independent from phylogeny and the Wheatsheaf test strongly supports convergence of the dorsal fin color between populations of species in the same type of water, with a similar trend suggested for the color of the dorsal lobe of the caudal fin. This means that simple color characters cannot necessarily be relied upon for taxonomic revisions of the genus as local phenotypic variants may represent environmentally determined plasticity or convergent evolution. Further studies are required to determine the validity of these characters.


Assuntos
Caraciformes , Animais , Filogenia , Nadadeiras de Animais/anatomia & histologia , Especiação Genética , Água
17.
Sci Rep ; 14(1): 3718, 2024 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355946

RESUMO

In contrast to adult mammals, zebrafish display a high capacity to heal injuries and repair damage to various organs. One of the earliest responses to injury in adult zebrafish is revascularization, followed by tissue morphogenesis. Tissue vascularization entails the formation of a blood vessel plexus that remodels into arteries and veins. The mechanisms that coordinate these processes during vessel regeneration are poorly understood. Hence, investigating and identifying the factors that promote revascularization and vessel remodeling have great therapeutic potential. Here, we revealed that fin vessel remodeling critically depends on Apela peptide. We found that Apela selectively accumulated in newly formed zebrafish fin tissue and vessels. The temporal expression of Apela, Apln, and their receptor Aplnr is different during the regenerative process. While morpholino-mediated knockdown of Apela (Mo-Apela) prevented vessel remodeling, exogenous Apela peptide mediated plexus repression and the development of arteries in regenerated fins. In contrast, Apela enhanced subintestinal venous plexus formation (SIVP). The use of sunitinib completely inhibited vascular plexus formation in zebrafish, which was not prevented by exogenous application. Furthermore, Apela regulates the expression of vessel remolding-related genes including VWF, IGFPB3, ESM1, VEGFR2, Apln, and Aplnr, thereby linking Apela to the vascular plexus factor network as generated by the STRING online database. Together, our findings reveal a new role for Apela in vessel regeneration and remodeling in fin zebrafish and provide a framework for further understanding the cellular and molecular mechanisms involved in vessel regeneration.


Assuntos
Hormônios Peptídicos , Peixe-Zebra , Animais , Nadadeiras de Animais/metabolismo , Receptores de Apelina/metabolismo , Mamíferos/metabolismo , Hormônios Peptídicos/metabolismo , Regeneração , Remodelação Vascular , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
18.
Bioinspir Biomim ; 19(2)2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38211345

RESUMO

Fish coordinate the motion of their fins and body to create the time-varying forces required for swimming and agile maneuvers. To effectively adapt this biological strategy for underwater robots, it is necessary to understand how the location and coordination of interacting fish-like fins affect the production of propulsive forces. In this study, the impact that phase difference, horizontal and vertical spacing, and compliance of paired fins had on net thrust and lateral forces was investigated using two fish-like robotic swimmers and a series of computational fluid dynamic simulations. The results demonstrated that the propulsive forces created by pairs of fins that interact through wake flows are highly dependent on the fins' spacing and compliance. Changes to fin separation of less than one fin length had a dramatic effect on forces, and on the phase difference at which desired forces would occur. These findings have clear implications when designing multi-finned swimming robots. Well-designed, interacting fins can potentially produce several times more propulsive force than a poorly tuned robot with seemingly small differences in the kinematic, geometric, and mechanical properties.


Assuntos
Robótica , Animais , Nadadeiras de Animais , Natação , Fenômenos Biomecânicos , Movimento (Física)
19.
Bioinspir Biomim ; 19(2)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38227952

RESUMO

Miniature blimps are lighter-than-air vehicles which have become an increasingly common unmanned aerial system research platform due to their extended endurance and collision tolerant design. The UNSW-C bio-inspired miniature blimp consists of a 0.5 m spherical mylar envelope filled with helium. Four fins placed along the equator provide control over the three translatory axes and yaw rotations. A gondola attached to the bottom of the blimp contains all the electronics and flight controller. Here, we focus on using the UNSW-C blimp as a platform to achieve autonomous flight in GPS-denied environments. The majority of unmanned flying systems rely on GPS or multi-camera motion capture systems for position and orientation estimation. However, such systems are expensive, difficult to set up and not compact enough to be deployed in real environments. Instead, we seek to achieve basic flight autonomy for the blimp using a low-priced and portable solution. We make use of a low-cost embedded neural network stereoscopic camera (OAK-D-PoE) for detecting and positioning the blimp while an onboard inertia measurement unit was used for orientation estimation. Flight tests and analysis of trajectories revealed that 3D position hold as well as basic waypoint navigation could be achieved with variance (<0.1 m). This performance was comparable to that when a conventional multi-camera positioning system (VICON) was used for localizing the blimp. Our results highlight the potentially favorable tradeoffs offered by such low-cost positioning systems in extending the operational domain of unmanned flight systems when direct line of sight is available.


Assuntos
Nadadeiras de Animais , Eletrônica , Animais , Redes Neurais de Computação
20.
Sci Adv ; 10(3): eadj5991, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38241378

RESUMO

Ancient bony fishes had heterocercal tails, like modern sharks and sturgeons, with asymmetric caudal fins and a vertebral column extending into an elongated upper lobe. Teleost fishes, in contrast, developed a homocercal tail characterized by two separate equal-sized fin lobes and the body axis not extending into the caudal fin. A similar heterocercal-to-homocercal transition occurs during teleost ontogeny, although the underlying genetic and developmental mechanisms for either transition remain unresolved. Here, we investigated the role of hox13 genes in caudal fin formation as these genes control posterior identity in animals. Analysis of expression profiles of zebrafish hox13 paralogs and phenotypes of CRISPR/Cas9-induced mutants showed that double hoxb13a and hoxc13a mutants fail to form a caudal fin. Furthermore, single mutants display heterocercal-like morphologies not seen since Mesozoic fossil teleosteomorphs. Relaxation of functional constraints after the teleost genome duplication may have allowed hox13 duplicates to neo- or subfunctionalize, ultimately contributing to the evolution of a homocercal tail in teleost fishes.


Assuntos
Evolução Biológica , Peixe-Zebra , Animais , Peixe-Zebra/genética , Genes Homeobox , Nadadeiras de Animais , Coluna Vertebral
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