scholarly journals Expression variations in Ectodysplasin-A gene (eda) may contribute to morphological divergence of scales in Haplochromine cichlids

2021 ◽  
Author(s):  
Maximilian Wagner ◽  
Sandra Bračun ◽  
Anna Duenser ◽  
Christian Sturmbauer ◽  
Wolfgang Gessl ◽  
...  
Keyword(s):  
Scale Development ◽  
Target Genes ◽  
Lake Tanganyika ◽  
Genetic Difference ◽  
Posterior Part ◽  
The Body ◽  
Morphological Divergence ◽  
Shape Variation ◽  
Haplochromine Cichlids ◽  
Cichlid Species

AbstractBackgroundElasmoid scales are one of the most common dermal appendages and can be found in almost all species of bony fish differing greatly in their shape. Whilst the genetic underpinnings behind elasmoid scale development have been investigated, not much is known about the mechanisms involved in the shaping of scales. To investigate the links between gene expression differences and morphological divergence, we inferred shape variation of scales from two different areas of the body (anterior and posterior) stemming from ten haplochromine cichlid species from different origins (Lake Tanganyika, Lake Malawi, Lake Victoria and riverine). Additionally, we investigated transcriptional differences of a set of genes known to be involved in scale development and morphogenesis in fish.ResultsWe found that scales from the anterior and posterior part of the body strongly differ in their overall shape, and a separate look on scales from each body part revealed similar trajectories of shape differences considering the lake origin of single investigated species. Above all, nine as well as 11 out of 16 target genes showed expression differences between the lakes for the anterior and posterior dataset, respectively. Whereas in posterior scales four genes (dlx5, eda, rankl and shh) revealed significant correlations between expression and morphological differentiation, in anterior scales only one gene (eda) showed such a correlation. Furthermore, eda displayed the most significant expression difference between species of Lake Tanganyika and species of the other two younger lakes. Finally, we found genetic differences in downstream regions of eda gene (e.g. in the eda-tnfsf13b inter-genic region) that are associated with observed expression differences. This is reminiscent of a genetic difference in the eda-tnfsf13b inter-genic region which leads to gain or loss of armour plates in stickleback.ConclusionThese findings provide evidence for cross-species transcriptional differences of an important morphogenetic factor, eda, which is involved in formation of ectodermal appendages. These expression differences appeared to be associated with morphological differences observed in the scales of haplochromine cichlids indicating potential role of eda mediated signal in divergent scale morphogenesis in fish.

Resembling the juvenile colour of host cichlid facilitates access of the guest cichlid to host territory

Behaviour ◽  
2009 ◽  
Vol 146 (6) ◽  
pp. 741-756 ◽  
Author(s):  
Haruki Ochi ◽  
Satoshi Awata
Keyword(s):  
Lake Tanganyika ◽  
The Body ◽  
Sufficient Evidence ◽  
Body Colour ◽  
Cichlid Species ◽  
Guest Species ◽  
Yellow Body ◽  
Black Bodies ◽  
Coexisting Species ◽  
Similar Body

AbstractIn two coexisting species with similar body colours, one species may acquire benefits from mimicking the body colour of the other species. In Lake Tanganyika, the zoobenthivorous cichlid Neolamprologus mustax preferentially exploits the territories of the algivorous cichlid Variabilichromis moorii as a feeding ground, even though other zoobenthivorous cichlid species are expelled from these territories. The yellow body colour of the guest species, N. mustax, resembles that of juveniles of the host species, V. moorii, adults of which have entirely black bodies. To estimate the effect of juvenile colour on aggression from conspecific adults, the responses of adult V. moorii to dummy fish of four colours (black, yellow, white, and blue) were observed in this lake system. Our observations clearly demonstrated that adult V. moorii were less aggressive toward yellow, white, and blue dummies compared to black ones, with a slight difference in response to the yellow and white or blue dummies. This study indicates that resembling the colour of host juveniles can facilitate access of the guest species to host territory, but does not provide sufficient evidence for a hypothesis that the guest species mimics the body colour of the host juvenile.

scholarly journals Redescription of Paradiplozoon hemiculteri (Monogenea, Diplozoidae) from the type host Hemiculter leucisculus, with neotype designation

Parasite ◽  
2018 ◽  
Vol 25 ◽  
pp. 4 ◽  
Author(s):  
Dagmar Jirsová ◽  
Xuejuan Ding ◽  
Kristína Civáňová ◽  
Eliška Jirounková ◽  
Jana Ilgová ◽  
...  
Keyword(s):  
Southern China ◽  
Phylogenetic Analyses ◽  
Posterior Part ◽  
Original Description ◽  
Molecular Data ◽  
The Body ◽  
Type Host ◽  
Hemiculter Leucisculus ◽  
Morphological And Molecular Data ◽  
Median Plate

Paradiplozoon hemiculteri (Ling, 1973), a member of the Diplozoidae, parasitizes the gills of Asian fish. Not only is the type material unavailable for this species, the original description was poor and somewhat conflicting, and adequate molecular data were not available. What is more, the available morphological and molecular data are inconsistent and fluctuate significantly. Here, we present a redescription of P. hemiculteri based on morphological and molecular data from new isolates collected from the type host, the sharpbelly Hemiculter leucisculus (Basilewsky, 1855), captured at the neotype locality (Shaoguan, Guangdong Province, southern China); a neotype for P. hemiculteri was designated from this collection. The length and width of the body, buccal suckers, pharynx, attachment clamps, sickle and the central hook handle were all measured and the shape of the anterior and posterior part of the median plate and anterior and posterior joining sclerites accurately documented. Phylogenetic analyses based on the sequences of the second rDNA internal transcribed spacer (ITS2) indicated that all new samples clustered together and differed clearly from sequences attributed to P. hemiculteri, which are deposited in GenBank. Our results confirm that P. hemiculteri is the only diplozoid that has demonstrably been found on the gills of H. leucisculus to date.

scholarly journals Early Palaeozoic dentine and patterned scales in the embryonic catshark tail

2007 ◽  
Vol 4 (1) ◽  
pp. 87-90 ◽  
Author(s):  
Zerina Johanson ◽  
Mikiko Tanaka ◽  
Natalie Chaplin ◽  
Moya Smith
Keyword(s):  
Scale Development ◽  
Sonic Hedgehog ◽  
The Body ◽  
Iterative Sequence ◽  
Histological Structure ◽  
Scyliorhinus Canicula ◽  
Pulp Cavity ◽  
Early Palaeozoic ◽  
Hedgehog Signal ◽  
Modular Nature

Regular scale patterning, restricted to the caudalmost tail and organized into two opposing rows on each side of the tail, is observed in few chondrichthyans. These evenly spaced scales, in dorsal and ventral rows, develop in an iterative sequence from the caudal tip, either side of the notochord. They are subsequently lost as a scattered pattern of placoid scales develops on the body and fins. An identical organized pattern is observed in tail scales of Scyliorhinus canicula (catshark), where the expression of sonic hedgehog signal is restricted to the epithelium of developing scales and remains localized to the scale pocket. Regulation of iterative scale position by sonic hedgehog is deeply conserved in vertebrate phylogeny. These scales also reveal an archaic histological structure of a dentine type found in the oldest known shark scales from the Ordovician and Silurian. This combination of regulated pattern and ancient dentine occurs only in the tail, representing the primary scalation. Scattered body scales in elasmobranchs such as S. canicula originate secondarily from differently regulated development, one with typical orthodentine around a central pulp cavity. These observations emphasize the modular nature of chondrichthyan scale development and illustrate previously undetected variation as an atavism in extant chondrichthyan dentine.

Interacting functions of snail, twist and huckebein during the early development of germ layers in Drosophila

Development ◽  
1994 ◽  
Vol 120 (5) ◽  
pp. 1137-1150 ◽  
Author(s):  
R. Reuter ◽  
M. Leptin
Keyword(s):  
Transcription Factors ◽  
Digestive Tract ◽  
Early Development ◽  
Target Genes ◽  
Anterior Part ◽  
Posterior Part ◽  
Germ Layers ◽  
Mesoderm Development ◽  
Ventral Furrow

Two zygotic genes, snail (sna) and twist (twi), are required for mesoderm development, which begins with the formation of the ventral furrow. Both twi and sna are expressed ventrally in the blastoderm, encode transcription factors and promote the invagination of the ventral furrow by activating or repressing appropriate target genes. However, sna and twi alone do not define the position of the ventral furrow, since they are also expressed in ventral cells that do not invaginate. We show that huckebein (hkb) sets the anterior and the posterior borders of the ventral furrow, but acts by different modes of regulation. In the posterior part of the blastoderm, hkb represses the expression of sna in the endodermal primordium (which we suggest to be adjacent to the mesodermal primordium). In the anterior part, hkb antagonizes the activation of target genes by twi and sna. Here, bicoid permits the co-expression of hkb, sna and twi, which are all required for the development of the anterior digestive tract. We suggest that mesodermal fate is determined where sna and twi but not hkb are expressed. Anteriorly hkb together with sna determines endodermal fate, and hkb together with sna and twi are required for foregut development.

The Body Image Psychological Inflexibility Scale: Development and psychometric properties

2015 ◽  
Vol 226 (1) ◽  
pp. 45-52 ◽  
Author(s):  
Glenn M. Callaghan ◽  
Emily K. Sandoz ◽  
Sabrina M. Darrow ◽  
Timothy K. Feeney
Keyword(s):  
Body Image ◽  
Scale Development ◽  
Psychometric Properties ◽  
The Body ◽  
Psychological Inflexibility

scholarly journals The Morpho-Functional Parameters of Rat Pituitary Hormone Producing Cells After Genistein Treatment

2018 ◽  
Vol 41 (1) ◽  
pp. 5-19 ◽  
Author(s):  
Svetlana Trifunović ◽  
Verica Milošević
Keyword(s):  
Replacement Therapy ◽  
Estrogen Replacement Therapy ◽  
Target Genes ◽  
Kinase Inhibitor ◽  
Endocrine System ◽  
The Body ◽  
Pituitary Hormone ◽  
Estrogen Replacement ◽  
Genistein Treatment ◽  
Rat Pituitary

AbstractPhytoestrogens are a diverse group of steroid–like compounds that occur naturally in many plants. There are various types of phytoestrogens, including the best-researched isoflavones which are commonly found in soy. The consumption of soy products has many health benefits, including protection against breast cancer, prostate cancer, menopausal symptoms, heart disease and osteoporosis. In contrast, use of hormonally active compounds-isoflavones may unfortunately interfere with the endocrine system and can have far-reaching consequences. Genistein, the most abundant soy-bean derived isoflavone, possesses a ring system similar to estrogens and acts through an estrogen receptor (ER)-mediated mechanism, by increasing or decreasing the transcription of ER-dependent target genes. Also, genistein can act on cells through ER non-dependent mechanisms, such as tyrosine kinase inhibitor. The neuroendocrine systems are responsible for the control of homeostatic processes in the body, including reproduction, growth, metabolism and energy balance, and stress responsiveness. It is well known, that estrogen is important for development of the neuroendocrine system in both sexes. At the pituitary level, estrogen is known to affect the regulation of all hormone producing (HP) cells, by direct and/or indirect mechanisms. Due to structural and functional resemblance to estrogen, the question may arise of whether and how genistein affects the morphofunctional features of pituitary HP cells. This review deals with the consequences of genistein’s effects on morphological, stereological and hormonal features of HP cells within the anterior pituitary gland. Transparency on this issue is needed because isoflavones are presently highly consumed. Inter alia, genistein as well as other isoflavones, are present in various dietary supplements and generally promoted as an accepted alternative to estrogen replacement therapy. Potential isoflavone biomedical exploitation is not only limited to estrogen replacement therapy, so it should be treated in a wider context of different ageing symptoms remediation.

scholarly journals Spatial and temporal variation in body mass and the blubber, muscle and visceral fat content of North Atlantic common minke whales

2020 ◽  
Vol 21 (1) ◽  
pp. 59-70
Author(s):  
Thorvaldur Gunnlaugsson
Keyword(s):  
Body Mass ◽  
North Atlantic ◽  
Visceral Fat ◽  
Energy Content ◽  
Posterior Part ◽  
The Body ◽  
Spatial And Temporal Variation ◽  
Total Body Mass ◽  
The North ◽  
Minke Whales

The exponent for predicting total body mass from length has been studied in many species and here data on common minke whales from areas in the North Atlantic is added from both Icelandic and Norwegian research catches. The exponent was found to be not significantly different from 3. In addition seasonal changes in body mass and in the parts of blubber, muscle and visceral fat are reported. The exponent for how blubber mass increases with length is lower than 3. In all cases a significant increase over the season was detected, in particular for the mature animals, and also in girth measurements, particularly at the posterior part of the body. Pregnant females had significantly more blubber than other whales. These results agree with studies on blubber thickness measurements and tissue energy content of Icelandic baleen whales and observed changes in the ecosystem around Iceland during the research period.

scholarly journals MUSCLE TENSION AND REFLEXES IN THE EARTHWORM

1923 ◽  
Vol 5 (3) ◽  
pp. 327-333 ◽  
Author(s):  
A. R. Moore
Keyword(s):  
Nerve Cord ◽  
Ventral Nerve Cord ◽  
Body Wall ◽  
Muscle Tension ◽  
Posterior Part ◽  
The Body ◽  
Entire Length ◽  
Sensory Cells ◽  
Ventral Region ◽  
Anterior Segments

1. By the use of preparations of earthworm in which the cutaneous receptors have been anesthetized with a solution of M/8 MgCl2, it is shown that peristalsis can be initiated by tension alone. 2. The receptors of the tension reflex are the intermyal sensory cells of the ventral region of the body wall. 3. It is concluded that Straub obtained the tension reflex because his preparations contained the intermyal receptors; Budington was unable to observe the tension reflex in any preparation from which the intermyal receptors had been removed. 4. Intermyal receptors are the receptors of the following reaction: Passive unilateral tension of the posterior part of an earthworm induces active homolateral tension of the musculature of the anterior segments, and results in the course of progress being brought into line with the enforced orientation of the tail. This reaction is termed the homostrophic reflex. 5. The receptors for the reaction are distributed throughout the entire length of the worm, the effectors are limited to the anterior 15 to 20 segments. The impulse is conducted by the ventral nerve cord. 6. The interaction of the homostrophic reflex and tropisms is considered.

Odontogenic keratocyst: diagnostic characteristics and conservative surgical treatment

2021 ◽  
pp. 1-12
Author(s):  
Javier Sánchez Sánchez ◽  
José Aguilar Maldonado ◽  
Karem Barreno Haro
Keyword(s):  
Third Molar ◽  
Posterior Part ◽  
En Bloc Resection ◽  
Bloc Resection ◽  
The Body ◽  
Odontogenic Keratocyst ◽  
High Recurrence Rate ◽  
En Bloc ◽  
Dental Lamina ◽  
Diagnostic Characteristics

Keratocyst is a benign odontogenic lesion with aggressive behavior, probably derived from the dental lamina. It is frequently located in the posterior part of the mandibular bone in the area of ​​the third molar, mandibular angle and can progress towards the ramus and the body, presenting a direct association with retained dental organs. There is a wide variety of techniques for the treatment of this lesion, such as decompression, marsupialization, enucleation, and en bloc resection, as well as the combination of these with adjuvant methods. The interest in this lesion stems from its high recurrence rate, which is estimated to be 20-30% in the general population, however, at present the use of conservative treatments such as marsupialization and decompression has been chosen. demonstrated greater effectiveness and less recurrence. This is why after treating the lesions it is important to give a long-term follow-up. The objective of the publication is to present the report of a clinical case of a 21-year-old male patient with a diagnosis of odontogenic keratocyst treated with a decompression technique for five months for subsequent surgical enucleation. It has been proven that decompression treatment followed by enucleation and accompanied by adjuvant methods is an adequate therapeutic management for keratocysts as it demonstrates its lower rate of recurrence and its noble behavior with neighboring vital structures. However, in all cases, regular monitoring should be carried out to prevent recurrence of the lesion.

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