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Effects of temperature on metamorphosis and endochondral ossification in Rana chensinensis tadpoles.Comparative Biochemistry and... Mar 2023Temperature is one of the important factors affecting the growth, development, and metamorphosis of amphibians. Endochondral ossification during metamorphosis plays a...
Temperature is one of the important factors affecting the growth, development, and metamorphosis of amphibians. Endochondral ossification during metamorphosis plays a crucial role in amphibian survival and adaptation on land. In this study, we explored the effects of different temperature treatments on the growth, development, and endochondral ossification of Rana chensinensis tadpoles during metamorphosis. The results showed that high temperature exposure may affect the skeletal development of tadpoles during metamorphosis, such as reduction of bone length and ossification of limbs, thyroid gland damage and change of ossification-related genes expression levels,and ultimately affect the movement and survival of tadpoles in the terrestrial environment. These results provide an experimental reference for further research on the effects of temperature on amphibian growth and development and provide an important theoretical basis for the decline of the amphibian population caused by temperature.
Topics: Animals; Larva; Osteogenesis; Temperature; Ranidae; Thyroid Gland; Metamorphosis, Biological
PubMed: 36657230
DOI: 10.1016/j.cbd.2023.101057 -
Insect Science Dec 2023Energy metabolism is essential for insect metamorphosis. The accumulation and utilization of energy is still not completely clear during larval-pupal metamorphosis of...
Energy metabolism is essential for insect metamorphosis. The accumulation and utilization of energy is still not completely clear during larval-pupal metamorphosis of holometabolous insects. We used metabolome and transcriptome analysis to reveal key metabolic changes in the fat body and plasma and the underlying metabolic regulation mechanism of Helicoverpa armigera, an important global agricultural insect pest, during larval-pupal metamorphosis. During the feeding stage, activation of aerobic glycolysis provided intermediate metabolites and energy for cell proliferation and lipid synthesis. During the non-feeding stages (the initiation of the wandering stage and the prepupal stage), aerobic glycolysis was suppressed, while, triglyceride degradation was activated in the fat body. The blocking of metabolic pathways in the fat body was probably caused by 20-hydroxyecdysone-induced cell apoptosis. 20-hydroxyecdysone cooperated with carnitine to promote the degradation of triglycerides and the accumulation of acylcarnitines in the hemolymph, allowing rapid transportation and supply of lipids from the fat body to other organs, which provided a valuable reference for revealing the metabolic regulation mechanism of lepidopteran larvae during the last instar. Carnitine and acylcarnitines are first reported to be key factors that mediate the degradation and utilization of lipids during larval-pupal metamorphosis of lepidopteran insects.
Topics: Animals; Ecdysterone; Pupa; Moths; Metamorphosis, Biological; Larva; Carnitine; Lipids; Insect Proteins
PubMed: 37200210
DOI: 10.1111/1744-7917.13201 -
Behavioral Neuroscience Dec 2019Many species of anuran amphibians (frogs and toads) undergo metamorphosis, a developmental process during which external and internal body morphologies transform... (Review)
Review
Many species of anuran amphibians (frogs and toads) undergo metamorphosis, a developmental process during which external and internal body morphologies transform dramatically as the animal transitions to a new ecosystem (from aquatic to terrestrial) and develops new behavior patterns (from filter-feeding to active pursuit of moving prey; from mostly mute to highly vocal). All sensory systems transform to some extent during metamorphosis, even in those "primitive" anuran species that remain fully aquatic in adult life. In this article, I review what is known about the development of the auditory system in anuran tadpoles. I identify crucial developmental windows for major maturational events in the ear and brainstem that showcase the structural and physiological reorganization of the substrates for hearing airborne sounds as the animal navigates the metamorphic transition. I argue that auditory development is dynamic and nonlinear, and I point out areas for future investigation. Understanding metamorphosis can shed light on how organisms adapt to major environmental challenges. (PsycINFO Database Record (c) 2019 APA, all rights reserved).
Topics: Animals; Anura; Auditory Pathways; Hearing; Larva; Metamorphosis, Biological; Sound
PubMed: 31448929
DOI: 10.1037/bne0000340 -
Cold Spring Harbor Protocols Aug 2021has been widely used as a model organism to study wound healing and regeneration. During early development and at tadpole stages, is a quick healer and is able to... (Review)
Review
has been widely used as a model organism to study wound healing and regeneration. During early development and at tadpole stages, is a quick healer and is able to regenerate multiple complex organs-abilities that decrease with the progression of metamorphosis. This unique capacity leads us to question which mechanisms allow and direct regeneration at stages before the beginning of metamorphosis and which ones are responsible for the loss of regenerative capacities during later stages. is an ideal model to study regeneration and has contributed to the understanding of morphological, cellular, and molecular mechanisms involved in these processes. Nevertheless, there is still much to learn. Here we provide an overview on using as a model organism to study regeneration and introduce protocols that can be used for studying wound healing and regeneration at multiple levels, thus enhancing our understanding of these phenomena.
Topics: Animals; Larva; Metamorphosis, Biological; Regeneration; Wound Healing; Xenopus laevis
PubMed: 33782095
DOI: 10.1101/pdb.top100966 -
Developmental Biology Jul 2022External environmental cues can have significant impacts on the timing and outcomes of animal development. For the swimming larvae of many marine invertebrates, the...
External environmental cues can have significant impacts on the timing and outcomes of animal development. For the swimming larvae of many marine invertebrates, the presence of specific surface-bound bacteria are important cues that help larvae identify a suitable location on the sea floor for metamorphosis and adult life. While metamorphosis in response to bacteria occurs in diverse animals from across the animal tree of life, we know little about the signal transduction cascades stimulated at the onset of metamorphosis upon their interaction with bacteria. The metamorphosis of a model tubeworm, Hydroides elegans, is triggered by the bacterium Pseudoalteromonas luteoviolacea which produces a stimulatory protein called Mif1. In this work, we define three key nodes in a signaling cascade promoting Hydroides metamorphosis in response to Mif1. Using metabolomic profiling, we find that the stimulation of Hydroides larvae by P. luteoviolacea leads to an increase in diacylglycerol during the initiation of metamorphosis, and that Mif1 is necessary for this upregulation. Genomic and pharmacological examination suggests that diacylglycerol triggers a phosphotransferase signaling cascade involving Protein Kinase C (PKC) and Mitogen-Activated Protein Kinase (MAPK), to induce Hydroides metamorphosis. Additionally, Mif1 activates the expression of two nuclear hormone receptors, HeNHR1 and HeNHR2 in the cerebral ganglia of Hydroides larvae. Our results define a post-translational signal transduction pathway mediating bacteria-stimulated metamorphosis in a model invertebrate animal.
Topics: Animals; Diglycerides; Larva; Metamorphosis, Biological; Mitogen-Activated Protein Kinases; Polychaeta; Protein Kinase C; Signal Transduction
PubMed: 35500661
DOI: 10.1016/j.ydbio.2022.04.009 -
International Journal of Molecular... Jan 2020Biofilms are critical components of most marine systems and provide biochemical cues that can significantly impact overall community composition. Although progress has...
Biofilms are critical components of most marine systems and provide biochemical cues that can significantly impact overall community composition. Although progress has been made in the bacteria-animal interaction, the molecular basis of modulation of settlement and metamorphosis in most marine animals by bacteria is poorly understood. Here, showing inducing activity on mussel settlement and metamorphosis was chosen as a model to clarify the mechanism that regulates the bacteria-mussel interaction. We constructed a flagellin synthetic protein gene deletion mutant of and checked whether deficiency of gene will impact inducing activity, motility, and extracellular polymeric substances of biofilms. Furthermore, we examined the effect of flagellar proteins extracted from bacteria on larval settlement and metamorphosis. The deletion of the gene caused the loss of the flagella structure and motility of the ∆ strain. Deficiency of the gene promoted the biofilm formation and changed biofilm matrix by reducing β-polysaccharides and increasing extracellular proteins and finally reduced biofilm-inducing activities. Flagellar protein extract promoted mussel metamorphosis, and ∆ biofilms combined with additional flagellar proteins induced similar settlement and metamorphosis rate compared to that of the wild-type strain. These findings provide novel insight on the molecular interactions between bacteria and mussels.
Topics: Animals; Bacterial Proteins; Biofilms; Bivalvia; China; Flagellin; Host Microbial Interactions; Larva; Marine Biology; Metamorphosis, Biological; Mutation; Mytilus; Pseudoalteromonas; Transcriptome
PubMed: 31973189
DOI: 10.3390/ijms21030710 -
Genetics Mar 2023During postembryonic life, hormones, including ecdysteroids, juvenile hormones, insulin-like peptides, and activin/TGFβ ligands act to transform the larval nervous... (Review)
Review
During postembryonic life, hormones, including ecdysteroids, juvenile hormones, insulin-like peptides, and activin/TGFβ ligands act to transform the larval nervous system into an adult version, which is a fine-grained mosaic of recycled larval neurons and adult-specific neurons. Hormones provide both instructional signals that make cells competent to undergo developmental change and timing cues to evoke these changes across the nervous system. While touching on all the above hormones, our emphasis is on the ecdysteroids, ecdysone and 20-hydroxyecdysone (20E). These are the prime movers of insect molting and metamorphosis and are involved in all phases of nervous system development, including neurogenesis, pruning, arbor outgrowth, and cell death. Ecdysteroids appear as a series of steroid peaks that coordinate the larval molts and the different phases of metamorphosis. Each peak directs a stereotyped cascade of transcription factor expression. The cascade components then direct temporal programs of effector gene expression, but the latter vary markedly according to tissue and life stage. The neurons read the ecdysteroid titer through various isoforms of the ecdysone receptor, a nuclear hormone receptor. For example, at metamorphosis the pruning of larval neurons is mediated through the B isoforms, which have strong activation functions, whereas subsequent outgrowth is mediated through the A isoform through which ecdysteroids play a permissive role to allow local tissue interactions to direct outgrowth. The major circulating ecdysteroid can also change through development. During adult development ecdysone promotes early adult patterning and differentiation while its metabolite, 20E, later evokes terminal adult differentiation.
Topics: Animals; Drosophila; Ecdysone; Ecdysteroids; Gene Expression Regulation, Developmental; Larva; Metamorphosis, Biological; Nervous System; Models, Animal
PubMed: 36645270
DOI: 10.1093/genetics/iyac184 -
General and Comparative Endocrinology Jan 2023Precisely regulated thyroid hormone (TH) signaling within tissues during frog metamorphosis gives rise to the organism-wide coordination of developmental events among...
Precisely regulated thyroid hormone (TH) signaling within tissues during frog metamorphosis gives rise to the organism-wide coordination of developmental events among organs required for survival. This TH signaling is controlled by multiple cellular mechanisms, including TH transport across the plasma membrane. A highly specific TH transporter has been identified, namely monocarboxylate transporter 8 (MCT8), which facilitates uptake and efflux of TH and is differentially and dynamically expressed among tissues during metamorphosis. We hypothesized that loss of MCT8 would alter tissue sensitivity to TH and affect the timing of tissue transformation. To address this, we used CRISPR/Cas9 to introduce frameshift mutations inslc16a2, the gene encoding MCT8, inXenopus laevis. We produced homozygous mutant tadpoles with a 29-bp mutation in the l-chromosome and a 20-bp mutation in the S-chromosome. We found that MCT8 mutants survive metamorphosis with normal growth and development of external morphology throughout the larval period. Consistent with this result, the expression of the pituitary hormone regulating TH plasma levels (tshb) was similar among genotypes as was TH response gene expression in brain at metamorphic climax. Further, delayed initiation of limb outgrowth during natural metamorphosis and reduced hindlimb and tail TH sensitivity were not observed in MCT8 mutants. In sum, we did not observe an effect on TH-dependent development in MCT8 mutants, suggesting compensatory TH transport occurs in tadpole tissues, as seen in most tissues in all model organisms examined.
Topics: Animals; Monocarboxylic Acid Transporters; Thyroid Hormones; Metamorphosis, Biological; Biological Transport; Mutation; Larva; Symporters
PubMed: 36427548
DOI: 10.1016/j.ygcen.2022.114179 -
Insect Molecular Biology Apr 2023Eukaryotic initiation factor 6 (eIF6) is necessary for ribosome biogenesis and translation, but eIF6 has been poorly elucidated in insects. Phylogenetic analysis...
Eukaryotic initiation factor 6 (eIF6) is necessary for ribosome biogenesis and translation, but eIF6 has been poorly elucidated in insects. Phylogenetic analysis demonstrated that eIF6 originated from one ancestral gene among animals and exhibited specific duplication in Tribolium, yielding three homologues in Tribolium castaneum, eIF6, eIF6-like 1 (eIF6l1), and eIF6-like 2 (eIF6l2). It was found that eIF6 was highly expressed in the embryonic and early adult stages, eIF6l1 had peak expression at the adult stage, and eIF6l2 showed peak expression in late adults of T. castaneum. Tissue-specific analyses in late-stage larvae demonstrated that eIF6 was abundantly expressed in all tissues, while eIF6l1 and eIF6l2 had the highest expression in the gut and the lowest expression in the head of T. castaneum. Knockdown of eIF6 caused precocious pupation and eclosion, impaired ovary and testis development and completely repressed egg production. The expression levels of vitellogenin 1 (Vg1), Vg2 and Vg receptor (VgR) significantly decreased in ds-eIF6 females 5 days post-adult emergence. Silencing eIF6 activated ecdysteroid biosynthesis and juvenile hormone degradation but reduced the activity of insulin signalling in T. castaneum, which might mediate its roles in metamorphosis, reproduction and gene expression regulation. However, silence of eIF6l1 or eIF6l2 had no effects on metamorphosis and reproduction in T. castaneum. This study provides comprehensive information for eIF6 evolution and function in the insect.
Topics: Female; Male; Animals; Tribolium; Phylogeny; Metamorphosis, Biological; Reproduction
PubMed: 36366777
DOI: 10.1111/imb.12817 -
Gene Expression Patterns : GEP Mar 2022In a high-throughput RNA sequencing analysis, comparing the transcriptional response between Xenopus laevis regenerative and non-regenerative stages to spinal cord...
BACKGROUND
In a high-throughput RNA sequencing analysis, comparing the transcriptional response between Xenopus laevis regenerative and non-regenerative stages to spinal cord injury, cornifelin was found among the most highly differentially expressed genes. Cornifelin is mainly expressed in stratified squamous epithelia, but its expression in the spinal cord and other central nervous structures has only been described during early development.
RESULTS
Here, we report cornifelin expression in the spinal cord, retina, and cornea throughout metamorphosis and in the spinal cord after injury. Cornifelin was detected in the grey matter and meninges of the spinal cord from NF-50 to NF-66, with decreased expression in the grey matter during metamorphosis. In the retina, cornifelin was expressed in the ganglion cell layer, the inner and outer nuclear layer, and the outer segment from NF-50 to NF-66. After spinal cord injury, we only observed cornifelin upregulation in NF-66 but no significant changes in NF-50. However, we found cornifelin positive cells in NF-50 meninges closing the spinal cord stumps 1 day after injury and delineating the borders of the spinal cord following the continuity of tissue regeneration in the following days after injury. Instead, in NF-66, cornifelin positive cells were distributed to the ventral side of the spinal cord at 6 days after injury, and at the injury gap at 10 days after injury.
CONCLUSIONS
Cornifelin is expressed in the Xenopus laevis spinal cord and eye during metamorphosis and plays a role in the meningeal response to spinal cord injury.
Topics: Animals; Metamorphosis, Biological; Spinal Cord; Spinal Cord Injuries; Xenopus laevis
PubMed: 35151892
DOI: 10.1016/j.gep.2022.119234