scholarly journals Sensory and skeletal development and growth in relation to the duration of the embryonic and larval stages in damselfishes (Pomacentridae)

2003 ◽  
Vol 80 (2) ◽  
pp. 187-206 ◽  
Author(s):  
KATHRYN D. KAVANAGH ◽  
ROSS A. ALFORD
Keyword(s):  
Skeletal Development ◽  
Larval Stages

scholarly journals Comparative description and ossification patterns of Dendropsophus labialis (Peters, 1863) and Scinax ruber (Laurenti, 1758)(Anura: Hylidae)

2017 ◽  
Author(s):  
Angélica Arenas Rodríguez ◽  
Juan Francisco Rubiano ◽  
Julio Mario Hoyos
Keyword(s):  
Comparative Studies ◽  
Skeletal Development ◽  
Spinal Column ◽  
Transverse Process ◽  
Life Cycles ◽  
Larval Stages ◽  
Staining Techniques ◽  
Ossification Sequences ◽  
Comparative Description ◽  
Ossification Sequence

Although comparative studies of anuran ontogeny have provided new data on heterochrony in the life cycles of frogs, most of them have not included Colombian species. Using different staining techniques, we describe the cranial and poscranial elements development in two hylid species, Scinax ruber and Dendropsophus labialis, providing new data for more comprehensive ontogenetic studies in Neotropical frogs. We examined specimens from Gosner stages 25 to 45. We found differences in the infrarostral and suprarostral cartilages, optic foramen, planum ethmoidale, and the gill apparatus. In the ossification sequence, one of the first elements to ossify were the transverse process of spinal column and atlas in both species, and the parasphenoid in the skull. New descriptions of skeletal development and ossification sequences of larval stages of these two species, especially data concerning the postcranium, contribute with useful information for analysis of sequential heterochrony, because although the hylids are widely known, there are few works (15 of 700 species) about ossification sequence that include the whole skeleton.

scholarly journals hdac4 mediates perichondral ossification and pharyngeal skeleton development in the zebrafish

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6167 ◽  
Author(s):  
April DeLaurier ◽  
Cynthia Lizzet Alvarez ◽  
Kali J Wiggins
Keyword(s):  
Histone Deacetylases ◽  
Stop Codon ◽  
Skeletal Development ◽  
Premature Stop Codon ◽  
Early Embryo ◽  
Loss Of Function ◽  
Larval Stages ◽  
Chondrocyte Maturation ◽  
Expression Of Genes ◽  
Maternal Contribution

Background Histone deacetylases (HDACs) are epigenetic factors that function to repress gene transcription by removing acetyl groups from the N-terminal of histone lysines. Histone deacetylase 4 (HDAC4), a class IIa HDAC, has previously been shown to regulate the process of endochondral ossification in mice via repression of Myocyte enhancer factor 2c (MEF2C), a transcriptional activator of Runx2, which in turn promotes chondrocyte maturation and production of bone by osteoblasts. Methods & Materials In this study, we generated two zebrafish lines with mutations in hdac4 using CRISPR/Cas9 and analyzed mutants for skeletal phenotypes and expression of genes known to be affected by Hdac4 expression. Results Lines have insertions causing a frameshift in a proximal exon of hdac4 and a premature stop codon. Mutations are predicted to result in aberrant protein sequence and a truncated protein, eliminating the Mef2c binding domain and Hdac domain. Zygotic mutants from two separate lines show a significant increase in ossification of pharyngeal ceratohyal cartilages at 7 days post fertilization (dpf) (p < 0.01, p < 0.001). At 4 dpf, mutant larvae have a significant increase of expression of runx2a and runx2b in the ceratohyal cartilage (p < 0.05 and p < 0.01, respectively). A subset of maternal-zygotic (mz) mutant and heterozygote larvae (40%) have dramatically increased ossification at 7 dpf compared to zygotic mutants, including formation of a premature anguloarticular bone and mineralization of the first and second ceratobranchial cartilages and symplectic cartilages, which normally does not occur until fish are approximately 10 or 12 dpf. Some maternal-zygotic mutants and heterozygotes show loss of pharyngeal first arch elements (25.9% and 10.2%, respectively) and neurocranium defects (30.8% and 15.2%, respectively). Analysis of RNA-seq mRNA transcript levels and in situ hybridizations from zygotic stages to 75–90% epiboly indicates that hdac4 is highly expressed in early embryos, but diminishes by late epiboly, becoming expressed again in larval stages. Discussion Loss of function of hdac4 in zebrafish is associated with increased expression of runx2a and runx2b targets indicating that a role for hdac4 in zebrafish is to repress activation of ossification of cartilage. These findings are consistent with observations of precocious cartilage ossification in Hdac4 mutant mice, demonstrating that the function of Hdac4 in skeletal development is conserved among vertebrates. Expression of hdac4 mRNA in embryos younger than 256–512 cells indicates that there is a maternal contribution of hdac4 to the early embryo. The increase in ossification and profound loss of first pharyngeal arch elements and anterior neurocranium in a subset of maternal-zygotic mutant and heterozygote larvae suggests that maternal hdac4 functions in cartilage ossification and development of cranial neural crest-derived structures.

scholarly journals Comparative description and ossification patterns of Dendropsophus labialis (Peters, 1863) and Scinax ruber (Laurenti, 1758)(Anura: Hylidae)

2017 ◽  
Author(s):  
Angélica Arenas Rodríguez ◽  
Juan Francisco Rubiano ◽  
Julio Mario Hoyos
Keyword(s):  
Comparative Studies ◽  
Skeletal Development ◽  
Spinal Column ◽  
Transverse Process ◽  
Life Cycles ◽  
Larval Stages ◽  
Staining Techniques ◽  
Ossification Sequences ◽  
Comparative Description ◽  
Ossification Sequence

Although comparative studies of anuran ontogeny have provided new data on heterochrony in the life cycles of frogs, most of them have not included Colombian species. Using different staining techniques, we describe the cranial and poscranial elements development in two hylid species, Scinax ruber and Dendropsophus labialis, providing new data for more comprehensive ontogenetic studies in Neotropical frogs. We examined specimens from Gosner stages 25 to 45. We found differences in the infrarostral and suprarostral cartilages, optic foramen, planum ethmoidale, and the gill apparatus. In the ossification sequence, one of the first elements to ossify were the transverse process of spinal column and atlas in both species, and the parasphenoid in the skull. New descriptions of skeletal development and ossification sequences of larval stages of these two species, especially data concerning the postcranium, contribute with useful information for analysis of sequential heterochrony, because although the hylids are widely known, there are few works (15 of 700 species) about ossification sequence that include the whole skeleton.

A scanning electron microscopic study of the veliger larvae of the scallop argopecten purpuratus

1988 ◽  
Vol 46 ◽  
pp. 284-285
Author(s):  
G.C. Bellolio ◽  
K.S. Lohrmann ◽  
E.M. Dupré
Keyword(s):  
Morphological Description ◽  
Electron Microscopic ◽  
Larval Stages ◽  
Scanning Electron Microscopic Study ◽  
The Pacific ◽  
Argopecten Purpuratus ◽  
Veliger Larvae ◽  
20 Nm ◽  
Ethanol Series ◽  
Scanning Electron

Argopecten purpuratus is a scallop distributed in the Pacific coast of Chile and Peru. Although this species is mass cultured in both countries there is no morphological description available of the development of this bivalve except for few characterizations of some larval stages described for culture purposes. In this work veliger larvae (app. 140 pm length) were examined by the scanning electron microscope (SEM) in order to study some aspects of the organogenesis of this species.Veliger larvae were obtained from hatchery cultures, relaxed with a solution of MgCl2 and killed by slow addition of 21 glutaraldehyde (GA) in seawater (SW). They were fixed in 2% GA in calcium free artificial SW (pH 8.3), rinsed 3 times in calcium free SW, and dehydrated in a graded ethanol series. The larvae were critical point dried and mounted on double scotch tape (DST). To permit internal view, some valves were removed by slightly pressing and lifting the tip of a cactus spine wrapped with DST, The samples were coated with 20 nm gold and examined with a JEOL JSM T-300 operated at 15 KV.

The effect of mTORC1 on postnatal skeletal development

2013 ◽  
Author(s):  
Mary Matthews ◽  
Andrew Zannettino ◽  
Stephen Fitter ◽  
Sally Martin
Keyword(s):  
Skeletal Development

Maternal vitamin D depletion disrupts neonatal skeletal development in mice

2015 ◽  
Author(s):  
Harriet Buckley ◽  
Stephanie Borg ◽  
Kirsty Nicholson ◽  
Mark Kinch ◽  
David Hughes ◽  
...  
Keyword(s):  
Vitamin D ◽  
Skeletal Development ◽  
Maternal Vitamin ◽  
Vitamin D Depletion

Larval and juvenile development of the Iceland cockle Ciliatocardium ciliatum (Fabricius, 1780) (Bivalvia: Cardiidae)

2020 ◽  
Vol 324 (2) ◽  
pp. 242-251
Author(s):  
L.P. Flyachinskaya ◽  
P.A. Lezin
Keyword(s):  
Lateral Position ◽  
Larval Shell ◽  
Subtidal Zone ◽  
Larval Stages ◽  
Posterior Shoulder ◽  
Blade Shape ◽  
The Right ◽  
Lateral Structures ◽  
Juvenile Development ◽  
Concentric Structure

The paper considers the development of Ciliatocardium ciliatum from the stage of straight hinge to juvenile. In the White Sea the spawning of C. ciliatum begins at the end of June, larvae at different stages of development occur in plankton until the end of September. The earliest of the larvae found had shell lengths of 123–130 µm. The paper first examined the anatomy and structure of the larval shell of C. ciliatum. During the development, the main stages of organogenesis were described and special attention was paid to the formation of the digestive and muscular systems. The digestive system begins to function when the larva reaches a size of 170–180 µm. The digestive gland has a two-blade shape and is shifted to the right side. The foot is formed at a size of 230 µm, the gill rudiments appear when the larva reaches 270 µm. The development of the larval shell and larval hinge of the mollusc is considered in detail. The development of the larval shell of C. ciliatum is similar to the development of other family members. Throughout all the larval stages, the shell has a rounded shape with a low umbos, and the prodissoconch II has a clearly visible concentric structure. The C. ciliatum larval hinge is characterized by weak differentiation and the absence of pronounced cardinal teeth typical for other Cardiidae. However, the lateral structures of the castle – ridges and flanges – are well developed. The ligament begins to form at a size of 240–250 µm and occupies a lateral position. The settlement of the cockle takes place in September in the subtidal zone. After the metamorphosis, a large radial sculpture is formed on the dissoconch and a number of small spikes are formed at the rib of the posterior shoulder.

Further Problems in the Interpretation and Homology of the Insect Ovipositor

1964 ◽  
Vol 96 (1-2) ◽  
pp. 405-417 ◽  
Author(s):  
G. G. E. Scudder
Keyword(s):  
Experimental Study ◽  
Normal Development ◽  
Organ Formation ◽  
Larval Stages ◽  
Insect Phylogeny ◽  
Correct Form ◽  
Developmental Capacity ◽  
Mode Of Development ◽  
Dual Origin

AbstractAn attempt is made to re-evaluate the data on the origin of the ovipositor in insects and to explain its mode of development in living forms. Comparative developmental data from other groups of animals is cited to substantiate the claim that part of the insect ectodermal genitalia is appendicular rather than sternal in origin. It is suggested that the primary abdominal segmental appendages have provided a source of competent tissue which through subtle changes in selection, has evolved along many pathways, to form the gonocoxae, the pleuropodia, the pseudoplacenta and perhaps the prolegs in many different taxa.It is shown, by aid of sections through the insect embryo and larval stages, that the primary embryonic segmental appendages on the abdomen, do not differentiate; there is no loss of tissue and it cannot be proven that such appendages have been lost in insect phylogeny. The fact that they are represented still in the modern embryo, indicates that they have been retained. To explain the observable developmental details, it is suggested that abdominal limb histogenesis is arrested or suppressed in normal development, but this limb tissue retains its competence to differentiate. Thus development may be initiated again at a later time in postembryonic life. In this manner, the original limb tissue is available for organ formation in the maturing insect.The study has suggested that the appendages on the eighth and ninth segments of the abdomen initiate but do not complete their development in the polypod embryo. Possibly the potential limb tissue is arrested in development because it has not undergone some vital change as regards its capacity to respond (competence) to an inductor, perhaps the inductor is not available or perhaps it is not available in the correct form.There is evidence to suggest that the developmental capacity of the limb anlagen are reduced with time, so that full limb formation is not possible in postembryonic life: this can explain the development of abdominal coxae in the Thysanura and hence gonocoxae in higher insects. It is noted that should Gustafson's suggestion that the eversible sacs and gonapophyses are homologous with primary segmental genitalic ampullae prove acceptable, then the female ectodermal genitalia in insects would appear to have a dual origin.It is emphasized that the speculation expressed are being subjected to experimental study in an attempt to verify the suggested ontogeny and phylogeny.

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