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1.
Nat Commun ; 11(1): 862, 2020 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-32054841

RESUMO

Complex hierarchical structure governs emergent properties in biopolymeric materials; yet, the material processing involved remains poorly understood. Here, we investigated the multi-scale structure and composition of the mussel byssus cuticle before, during and after formation to gain insight into the processing of this hard, yet extensible metal cross-linked protein composite. Our findings reveal that the granular substructure crucial to the cuticle's function as a wear-resistant coating of an extensible polymer fiber is pre-organized in condensed liquid phase secretory vesicles. These are phase-separated into DOPA-rich proto-granules enveloped in a sulfur-rich proto-matrix which fuses during secretion, forming the sub-structure of the cuticle. Metal ions are added subsequently in a site-specific way, with iron contained in the sulfur-rich matrix and vanadium coordinated by DOPA-catechol in the granule. We posit that this hierarchical structure self-organizes via phase separation of specific amphiphilic proteins within secretory vesicles, resulting in a meso-scale structuring that governs cuticle function.


Assuntos
Materiais Revestidos Biocompatíveis/química , Metaloproteínas/química , Mytilus edulis/química , Estruturas Animais/anatomia & histologia , Estruturas Animais/química , Estruturas Animais/ultraestrutura , Animais , Di-Hidroxifenilalanina/química , Imageamento Tridimensional , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Mytilus edulis/anatomia & histologia , Mytilus edulis/ultraestrutura , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Vesículas Secretórias/química , Vesículas Secretórias/ultraestrutura
2.
Naturwissenschaften ; 106(9-10): 50, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31456022

RESUMO

The cavities of bamboos (Poaceae) are used by various animals. Most of the animals access these cavities either by existing cracks or by excavating bamboos with soft walls or small, thin-walled bamboos. Only a few animals excavate into the cavities of large and thick- and hard-walled internodes of mature bamboos. We studied two lizard beetle species (Coleoptera: Erotylidae: Languriinae), Doubledaya ruficollis and Oxylanguria acutipennis, that excavate into large internode cavities of recently dead mature bamboos and have morphological modifications. We observed that females of D. ruficollis used their mandibles to bore oviposition holes on Schizostachyum sp. (mean wall thickness = 3.00 mm) and O. acutipennis did so on Dendrocalamus sp. (3.37 mm) bamboos. Previous studies suggested that the markedly asymmetrical mandibles and needle-like ovipositors of females in the genus Doubledaya are adaptive traits for excavating hard-walled bamboos for oviposition. Therefore, we measured their mandibular lengths and ovipositor lengths. D. ruficollis females had greater asymmetry in the mandibles and shorter and less-sclerotized ovipositors than females of congeners using small bamboos. In contrast, O. acutipennis females had slightly asymmetrical mandibles and elongated, well-sclerotized ovipositors. Oviposition holes of D. ruficollis were cone-shaped (evenly tapering), whereas those of O. acutipennis were funnel-shaped (tube-like at the internal apex). This suggests that D. ruficollis females excavate oviposition holes using the mandibles only, and O. acutipennis females use both the mandibles and ovipositors. These differences suggest different oviposition-associated morphological specialization for using large bamboos: the extremely asymmetrical mandibles in D. ruficollis and elongated, needle-like ovipositors in O. acutipennis.


Assuntos
Besouros/anatomia & histologia , Besouros/fisiologia , Estruturas Animais/anatomia & histologia , Animais , Comportamento Animal/fisiologia , Feminino , Tamanho do Órgão/fisiologia , Poaceae/anatomia & histologia , Poaceae/parasitologia
3.
Biol Bull ; 237(1): 1-15, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31441702

RESUMO

The pen, or gladius, of the squid is an internalized shell. It serves as a site of attachment for important muscle groups and as a protective barrier for the visceral organs. The pen's durability and flexibility are derived from its unique composition of chitin and protein. We report the characterization of the structure, development, and composition of pens from Doryteuthis pealeii. The nanofibrils of the polysaccharide ß-chitin are arranged in an aligned configuration in only specific regions of the pen. Chitin is secreted early in development, enabling us to characterize the changes in pen morphology prior to hatching. The chitin and proteins are assembled in the shell sac surrounded by fluid that has a significantly different ionic composition from squid plasma. Two groups of proteins are associated with the pen: those on its surface and those embedded within the pen. Only 20 proteins are identified as embedded within the pen. Embedded proteins are classified into six groups, including chitin associated, protease, protease inhibitors, intracellular, extracellular matrix, and those that are unknown. The pen proteins share many conserved domains with proteins from other chitinous structures. We conclude that the pen is one of the least complex, load-bearing, chitin-rich structures currently known and is amenable to further studies to elucidate natural construction mechanisms using chitin and protein.


Assuntos
Quitina/metabolismo , Decapodiformes/anatomia & histologia , Proteínas/metabolismo , Estruturas Animais/anatomia & histologia , Estruturas Animais/química , Estruturas Animais/crescimento & desenvolvimento , Animais , Decapodiformes/química , Decapodiformes/crescimento & desenvolvimento
4.
Biol Bull ; 237(1): 36-47, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31441703

RESUMO

The pteropod mollusc Clione limacina is a feeding specialist, preying on shelled pteropods of the genus Limacina. Specialized prey-capture structures, called buccal cones, are hydraulically everted from within the mouth to capture the prey. Once captured, the prey is manipulated so the shell opening is over the mouth of Clione. Analyses of high-speed cine sequences of prey capture suggest that the mouth is actively opened rather than passively forced open by buccal cone eversion. The inflated buccal cones are initially straight and form a wide angle (maximum, 113°) prior to prey contact. Individual buccal cones bend orally following prey contact, suggesting a sensory trigger. To determine the muscular basis of buccal cone movements, the musculature of the buccal cones is described. Three distinct muscle fiber types include circular smooth muscle, longitudinal smooth muscle, and longitudinal striated muscle. The organization, distribution, and innervation of the muscle types suggest that circular muscle is used during buccal cone eversion, longitudinal smooth muscle is used for buccal cone withdrawal, and longitudinal striated muscle is used for oral bending of the buccal cones after prey contact and for manipulation of the prey.


Assuntos
Clione/anatomia & histologia , Comportamento Alimentar/fisiologia , Estruturas Animais/anatomia & histologia , Animais , Clione/fisiologia , Músculo Liso/anatomia & histologia , Músculo Liso/inervação , Músculo Estriado/anatomia & histologia , Músculo Estriado/inervação
5.
PLoS One ; 14(4): e0214889, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30995262

RESUMO

Atractaspidines are poorly studied, fossorial snakes that are found throughout Africa and western Asia, including the Middle East. We employed concatenated gene-tree analyses and divergence dating approaches to investigate evolutionary relationships and biogeographic patterns of atractaspidines with a multi-locus data set consisting of three mitochondrial (16S, cyt b, and ND4) and two nuclear genes (c-mos and RAG1). We sampled 91 individuals from both atractaspidine genera (Atractaspis and Homoroselaps). Additionally, we used ancestral-state reconstructions to investigate fang and diet evolution within Atractaspidinae and its sister lineage (Aparallactinae). Our results indicated that current classification of atractaspidines underestimates diversity within the group. Diversification occurred predominantly between the Miocene and Pliocene. Ancestral-state reconstructions suggest that snake dentition in these taxa might be highly plastic within relatively short periods of time to facilitate adaptations to dynamic foraging and life-history strategies.


Assuntos
Viperidae/classificação , Viperidae/genética , Estruturas Animais/anatomia & histologia , Estruturas Animais/fisiologia , Animais , Citocromos b/genética , Evolução Molecular , Genes Mitocondriais , Genes RAG-1 , Genes mos , NADH Desidrogenase/genética , Filogenia , Comportamento Predatório , RNA Ribossômico 16S/genética , Fatores de Tempo , Viperidae/fisiologia
6.
PLoS One ; 14(3): e0213268, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30893324

RESUMO

Surazomus saturninoae sp. nov. is described from eastern Amazon. The male has a pentagonal flagellum, similar to those of three other species in the genus. These four species are herein gathered as the arboreus-group of Surazomus. We present a brief synopsis of chaetotaxy description in hubbardiines and several homology proposals for the flagellum of the species in the arboreus-group: the posterior lobes may be homologous to the lateral lobes of hubbardiine species with trilobed flagella; the setal brush with 4-5 setae on the posterior lobe may be composed of one Dl2 seta and enlarged lobular microsetae; the single, median posterior coupling pocket may be homologous to the pair of posterior pockets seen in other hubbardiines; the single, median anterior coupling pocket may be homologous to the pair of pockets on the anterior border of the flagellum seen in other hubbardiines. Based on the morphology of these pockets and the chelicerae within Surazomus, we discuss the anchoring mechanism during the mating march.


Assuntos
Aracnídeos/classificação , Aracnídeos/fisiologia , Flagelos/fisiologia , Reprodução , Sensilas/fisiologia , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Aracnídeos/anatomia & histologia , Feminino , Masculino , Sensilas/anatomia & histologia
7.
PLoS One ; 14(2): e0213318, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30818343

RESUMO

In phytophagous sap-sucking insects, the precibarial valve plays an important role in sap ingestion. We used light and electron microspcopy to study the morphology and the ultrastructure of the precibarial valve of the meadow spittlebug, Philaenus spumarius (Hemiptera, Aphrophoridae), in order to better understand the operative mechanism of this structure. The precibarial valve revealed to be a complex structure with a bell-like invagination in the middle of the precibarium (on the epipharynx). Unlike the current hypothesis, we propose that the valve opens by dilator muscles and closes through cuticular and fluid tensions, the latter leading to morphological changes to the plane of the valve based on sap flow. Moreover, the presence of a precibarial secretory structure is described for the first time for auchenorrhynchan insects. In light of these observations, functions are hypothesized and discussed for this secretory structure.


Assuntos
Hemípteros/anatomia & histologia , Estruturas Animais/anatomia & histologia , Estruturas Animais/fisiologia , Estruturas Animais/ultraestrutura , Animais , Hemípteros/fisiologia , Hemípteros/ultraestrutura , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Boca/anatomia & histologia , Boca/fisiologia , Boca/ultraestrutura , Faringe/anatomia & histologia , Faringe/fisiologia , Faringe/ultraestrutura
8.
Acta Parasitol ; 64(1): 138-147, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30637560

RESUMO

BACKGROUND : Tetraonchidae is a small and relatively monomorphic family of dactylogyroid monogeneans. Since the morphology of sclerites of the attachment organ (haptor) is one of the primary criteria in tetraonchid taxonomy, the confocal study of sclerites and associated musculature may provide valuable taxonomic information. PURPOSE : The aim of this study was to examine the haptoral sclerites and musculature in Tetraonchus monenteron (Wagener, 1857), a common parasite of pike. METHODS: Haptoral musculature of T. monenteron was studied using phalloidin staining and confocal microscopy, with sclerites visualized in the reflection confocal mode. RESULTS: Haptoral armature of T. monenteron consists of ventral and dorsal pairs of anchors, a ventral bar, eight pairs of marginal hooks and at least three pairs of accessory sclerites. Anchors are operated by 14 muscles, of which the most prominent are extrinsic muscles, the transverse muscle interconnecting the ventral anchors, three muscles connecting the ventral anchor to the ventral bar, and four muscles of the dorsal and ventral anchors inserting on the haptoral wall. The extrinsic muscles are attached to the braceshaped sclerites, which in turn are connected to the dorsal anchors via muscle bundles. CONCLUSION: The gaffing action of the dorsal anchors is likely to be achieved by the extrinsic muscles and the transverse muscle that clamps the extrinsic muscles against the body wall. The ventral anchors are probably held in attached position by the transverse muscle and four muscles inserting on the ventral bar and haptoral wall. The haptoral musculature may have potential utility for tetraonchid taxonomy.


Assuntos
Estruturas Animais/anatomia & histologia , Músculos/anatomia & histologia , Platelmintos/anatomia & histologia , Animais , Microscopia Confocal , Microscopia de Fluorescência , Faloidina/análise , Coloração e Rotulagem
9.
J Helminthol ; 93(3): 356-366, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-29661266

RESUMO

Four strains of entomopathogenic nematodes were isolated with a live trap method in southern Poland. The isolates were identified as Steinernema silvaticum based on morphological, morphometric and molecular data. Infective juveniles of Polish S. silvaticum isolates differ in body length from S. weiseri (951 vs 740 µm, respectively), and in the hyaline tail portion from S. kraussei (48 vs 38%, respectively). First-generation males of S. silvaticum are longer than those of S. kraussei, S. weiseri and S. ichnusae (1829 vs 1400, 1180 and 1341 µm, respectively). Males of S. silvaticum and a sister species S. kraussei can be distinguished by the distance from the anterior end to the nerve ring (142 vs 105 µm), spicule (66 vs 49 µm) and gubernaculum length (45 vs 33 µm), and the presence of a mucron. The analysis of internal transcribed spacer (ITS), D2-D3 and cox1 sequences of the tested nematodes revealed differences of 3-5%, 3% and 12-13%, respectively, from S. kraussei strains. The phylogeny of both nuclear and mitochondrial genes indicated close relationships of the Polish S. silvaticum isolates with S. kraussei, S. oregonense and S. cholashanense. The reproductive isolation of the studied isolates was confirmed by hybridization tests with other European feltiae-kraussei group representatives. This study has supplemented the original description of S. silvaticum with morphological and morphometric characterization of the first-generation males and females. This is also the first molecular study of this species based on a multi-gene approach.


Assuntos
Filogenia , Rabditídios/classificação , Rabditídios/isolamento & purificação , Estruturas Animais/anatomia & histologia , Animais , Biometria , Análise por Conglomerados , DNA de Helmintos/química , DNA de Helmintos/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Variação Genética , Microscopia , Polônia , Rabditídios/anatomia & histologia , Rabditídios/genética , Análise de Sequência de DNA
10.
Int J Biol Macromol ; 126: 1282-1287, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30590149

RESUMO

Silk is an excellent natural fiber, which has been widely used in versatile fields. Silk spinning is a complex process involving the larval spinneret. The spinneret is essential for silk spinning, but the sectional morphology of the spinneret that determines the silk monofilament, the muscular activities around the silk press as well as the relationships between the spinneret and the properties of the resulting silk remain poorly understood. We studied these factors by dissecting the spinneret and analyzing silk from different Bombyx mori strains. The sectional morphology of silk monofilament was found to be largely determined by the spinneret, especially by the silk press. Moreover, contractile activity of the muscles around the silk press is high, and the contraction frequency of the muscles was estimated to range from 11.42 to 50 HZ. A comparison of the fibroin filaments before they entered the common tube indicated that the spinneret determines both silk shape and silk size. This study provides insight into the silk spinning process, which may help develop bionic spinning in further studies and also provides a rationale to study the effect of the spinneret on silk fineness at the molecular level.


Assuntos
Estruturas Animais/anatomia & histologia , Bombyx/anatomia & histologia , Seda/normas , Animais , Fenômenos Mecânicos , Estresse Mecânico
11.
Gen Comp Endocrinol ; 278: 50-57, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30077792

RESUMO

There is much interest in targeting neuropeptide signaling for the development of new and environmentally friendly insect control chemicals. In this study we have focused attention on the peptidergic control of the adult crop of Delia radicum (cabbage root fly), an important pest of brassicas in European agriculture. The dipteran crop is a muscular organ formed from the foregut of the digestive tract and plays a vital role in the processing of food in adult flies. We have shown using direct tissue profiling by MALDI-TOF mass spectrometry that the decapeptide myosuppressin (TDVDHVFLRFamide) is present in the crop nerve bundle and that application of this peptide to the crop potently inhibits the spontaneous contractions of the muscular lobes with an IC50 of 4.4 × 10-8 M. The delivery of myosuppressin either by oral administration or by injection had no significant detrimental effect on the adult fly. This failure to elicit a response is possibly due to the susceptibility of the peptide to degradative peptidases that cleave the parent peptide to inactive fragments. Indeed, we show that the crop of D. radicum is a source of neuropeptide-degrading endo- and amino-peptidases. In contrast, feeding benzethonium chloride, a non-peptide agonist of myosuppressin, reduced feeding rate and increased the rate of mortality of adult D. radicum. Current results are indicative of a key role for myosuppressin in the regulation of crop physiology and the results achieved during this project provide the basis for subsequent studies aimed at developing insecticidal molecules targeting the peptidergic control of feeding and food digestion in this pest species.


Assuntos
Estruturas Animais/anatomia & histologia , Brassica/parasitologia , Dípteros/anatomia & histologia , Sequência de Aminoácidos , Estruturas Animais/inervação , Animais , Dípteros/fisiologia , Contração Muscular , Peptídeo Hidrolases/metabolismo , Peptídeos/química
12.
Mol Ecol ; 27(24): 5049-5072, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30357984

RESUMO

Among the most dramatic examples of sexual selection are the weapons used in battles between rival males over access to females. As with ornaments of female choice, the most "exaggerated" sexually selected weapons vary from male to male more widely than other body parts (hypervariability), and their growth tends to be more sensitive to nutritional state or physiological condition compared with growth of other body parts ("heightened" conditional expression). Here, we use RNAseq analysis to build on recent work exploring these mechanisms in the exaggerated weapons of beetles, by examining patterns of differential gene expression in exaggerated (head and thorax horns) and non-exaggerated (wings, genitalia) traits in the Asian rhinoceros beetle, Trypoxylus dichotomus. Our results suggest that sexually dimorphic expression of weaponry involves large-scale changes in gene expression, relative to other traits, while nutrition-driven changes in gene expression in these same weapons are less pronounced. However, although fewer genes overall were differentially expressed in high- vs. low-nutrition individuals, the number of differentially expressed genes varied predictably according to a trait's degree of condition dependence (head horn > thorax horn > wings > genitalia). Finally, we observed a high degree of similarity in direction of effects (vectors) for subsets of differentially expressed genes across both sexually dimorphic and nutritionally responsive growth. Our results are consistent with a common set of mechanisms governing sexual size dimorphism and condition dependence.


Assuntos
Estruturas Animais/anatomia & histologia , Besouros/anatomia & histologia , Caracteres Sexuais , Comportamento Sexual Animal , Animais , Besouros/genética , Feminino , Masculino , Análise de Sequência de RNA , Transcriptoma
13.
Microsc Res Tech ; 81(12): 1513-1519, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30351532

RESUMO

Aphidius gifuensis Ashmaed parasitizes several species of aphids that cause economic damage to globally important crops; however, the mechanism of host location in this species is unclear. Here, we studied the sensory system in A. gifuensis to explore the likely mechanisms of host location that could be useful in the improved application of this species in aphid biological control programs. We used scanning electron microscopy to observe the external morphologies of the sensilla recorded from the entire body of female and male A. gifuensis. We recorded 16-18 segments and five types of sensilla on female antennae, including Böhm bristle, Chaetica sensillum, basiconic sensillum, trichoid sensillum, and placodea sensillum. The male antennae consisted of 18-20 segments, and distribution of sensilla was similar to female antennae with minor differences. No hole on the surface or tip of the sensilla was observed. Interestingly, scattered pores around the TS were found on the entire body of females, but only from the antennae, abdomen, and thoracic legs in males. TS was the most abundant and widely distributed sensillum. Tympana structures were found on antennae and femur of thoracic legs. Antenna cleaner was found on the tibia of propodeum and wing cleaner was found on the tibia of metapedes. Special crevice-shaped structures were found on the abdomen in both sexes, whereas strip-shaped structures were found only on the abdomen of females. Possible functions of the sensilla in relation to their morphologies are discussed.


Assuntos
Estruturas Animais/ultraestrutura , Himenópteros/ultraestrutura , Sensilas/ultraestrutura , Estruturas Animais/anatomia & histologia , Animais , Feminino , Himenópteros/anatomia & histologia , Masculino , Microscopia Eletrônica de Varredura , Sensilas/anatomia & histologia
14.
J Morphol ; 279(11): 1615-1628, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30368877

RESUMO

Hypophthalmichthys molitrix, silver carp, is an invasive Asian carp that has become increasingly widespread and ecologically destructive within the upper Mississippi River Basin. Its complex trophic anatomy may help explain the apparent efficiency with which they consume phytoplankton, outcompeting native filter feeders. This cypriniform species is characterized by trophic synapomorphies that include a palatal organ, loss of upper pharyngeal jaws, and a hypertrophied lower pharyngeal jaw. However, in silver carp these structures have become greatly modified and diverge from the more basal condition that characterizes species such as goldfish. The trophic apparatus of silver carp is composed of discrete structures that are functionally coupled: filtering plates, paired epibranchial organs (EBO), a modified palatal organ composed of large muscular folds that interdigitate with the filtering plates, and hypertrophied lower pharyngeal jaws and teeth. The filtering plates fill a significant portion of the buccal cavity, especially since the distal parts of these filtering plates make up a key component of the EBOs. EBOs, food aggregating structures found in many teleosts, are thought to have independently evolved at least six times. Ranging in complexity from small slits on the dorsal wall of the pharyngeal cavity to exceedingly intricate spiraling structures, EBOs are morphologically diverse among filter-feeding fishes. Despite this morphological diversity and broad taxonomic distribution, little is known regarding the functional anatomy of the EBO. Moreover, the EBO in silver carp is distinct from the organs previously described in other species, being created by four independent pharyngeal involutions (instead of the more typical one or two) that form spiral-shaped pharyngeal tubes surrounded by circumferential muscle. On each side of the head greatly hypertrophied hyomandibulae and opercles are connected to the anterior cartilaginous caps of the bilateral EBOs via enlarged muscles. Given that these fish are pump filter feeders we hypothesize that the opercula may compress and expand the EBOs during pumping causing food to be moved posteriorly toward the pharyngeal jaws.


Assuntos
Estruturas Animais/anatomia & histologia , Carpas/anatomia & histologia , Estruturas Animais/citologia , Estruturas Animais/ultraestrutura , Animais , Brânquias/anatomia & histologia , Músculos/anatomia & histologia , Músculos/diagnóstico por imagem , Faringe/anatomia & histologia , Microtomografia por Raio-X
15.
J Morphol ; 279(11): 1640-1653, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30368890

RESUMO

Bioluminescent organs have evolved many times within teleost fishes and exhibit a wide range of complexity and anatomical derivation. Although some bioluminescent organs have been studied in detail, the morphology of the bacterial light organs in glowbellies (Acropoma) is largely unknown. This study describes the anatomy of the bioluminescent organs in Haneda's Glowbelly (Acropoma hanedai) and the Glowbelly (Acropoma japonicum) and places the evolution of this light-producing system in the context of a new phylogeny of glowbellies and their relatives. Gross and histological examination of the bioluminescent organs indicate that they are derived from perianal ectodermal tissue, likely originating from the developmental proctodeum, contrary to at least one prior suggestion that the bioluminescent organ in Acropoma is of endodermal intestinal derivation. Additionally, anterior bioluminescent organ development in both species is associated with lateral spreading of the bacteria-containing arms of the bioluminescent organ from an initial median structure. In the context of a 16-gene molecular phylogeny, the bioluminescent organ in Acropoma is shown to have evolved within the Acropomatidae in the ancestor of Acropoma. Further, ancestral-states reconstruction demonstrates that the bioluminescent organs in Acropoma evolved independently from the light organs in related howellid and epigonid taxa which have esophageal or intestinally derived bioluminescent organs. Across the acropomatiforms, our reconstructions indicate that bioluminescent organs evolved independently four or five times. Based on the inferred phylogeny of the order where Acropoma and Doederleinia were separated from other traditional acropomatids, the familial taxonomy of the Acropomatidae was modified such that the previously described Malakichthyidae and Synagropidae were recognized. We also morphologically diagnose and describe the family Lateolabracidae.


Assuntos
Estruturas Animais/anatomia & histologia , Peixes/anatomia & histologia , Peixes/classificação , Luminescência , Filogenia , Animais
16.
J Insect Sci ; 18(5)2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30304508

RESUMO

Ambrosia beetles (Coleoptera: Curculionidae: Scolytinae and Platypodinae) rely on a symbiosis with fungi for their nutrition. Symbiotic fungi are preserved and transported in specialized storage structures called mycangia. Although pivotal in the symbiosis, mycangia have been notoriously difficult to study, given their minute size and membranous structure. We compared the application of novel visualization methods for the study of mycangia, namely micro-computed tomography (micro-CT) and laser ablation tomography (LATscan) with traditional paraffin sectioning. Micro-CT scanning has shown the greatest promise in new organ discovery, while sectioning remains the only method with sufficient resolution for cellular visualization. All three common types of mycangia (oral, mesonotal, and pronotal) were successfully visualized and presented for different species of ambrosia beetles: Ambrosiodmus minor (Stebbing) 1909, Euplatypus compositus (Say) 1823, Premnobius cavipennis Eichhoff 1878, Scolytoplatypus raja Blandford 1893, Xylosandrus crassiusculus (Motschulsky) 1866 and X. amputatus (Blandford) 1894. A reconstruction of the mycangium and the surrounding musculature in X. amputatus is also presented. The advantages of micro-CT compared to the previously commonly used microtome sectioning include the easy visualization and recording of three-dimensional structures, their position in reference to other internal structures, the ability to distinguish natural aberrations from technical artifacts, and the unprecedented visualizations of the anatomic context of mycangia enabled by the integrated software.


Assuntos
Estruturas Animais/anatomia & histologia , Inclusão em Parafina/métodos , Tomografia/métodos , Gorgulhos/anatomia & histologia , Animais , Fungos/fisiologia , Simbiose , Gorgulhos/microbiologia , Gorgulhos/fisiologia , Microtomografia por Raio-X/métodos
17.
PLoS One ; 13(9): e0204432, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30261078

RESUMO

The multi-plated skeleton of echinoids is made of the stereom, a light-weight construction which resembles a micro-beam framework. Although the two-dimensional design of the stereom has been studied, its spatial architecture is only little known. It is, however, imperative to understand the spatial architecture of the trabecular system in order to interpret its structural principles of this load-bearing construction. The echinoid's trabecular system is thus analyzed in-depth with respect to eight topological descriptors. The echinoid's plates are divided into two regions, the center of which consists of an unordered stereom, and the margin which consists of an ordered stereom. The eight trabecular descriptors indicate that the basal topology of the two plate regions are similar. The trabecular system predominantly consists of short and stocky trabeculae that show little tortuosity. The majority of trabeculae intersect in a 3N configuration, where three trabeculae intersect in one common node. Trabeculae in the 3N configuration intersect in an angle of around 120° resulting in a planar and triangular motif. These planar elements, when arranged in an angular off-set, can resist multi-dimensional loads. Results also show that the trabecular orientation perpendicular to the plate's surface is at an angle of 60°. The trabecular orientation in the plate's horizontal plane is directional. Both trabecular orientations reflect a construction which is capable of resisting applied loads and can distribute these loads over the entire skeleton. The spatial architecture of the echinoid's trabecular system is thus considered to be a performative light-weight and load-bearing system.


Assuntos
Estruturas Animais/anatomia & histologia , Ouriços-do-Mar/anatomia & histologia , Animais , Fenômenos Biomecânicos , Modelos Biológicos , Microtomografia por Raio-X
18.
In Vitro Cell Dev Biol Anim ; 54(8): 545-548, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30083840

RESUMO

Research of epithelial cells in musk gland is lacking. There are no good characterized epithelial cell lines that can provide complementary in vitro models for in vivo research. We successfully cultivated epithelial cells of musk gland for the first time. The protocol described here produces epithelial cell lines from the mature secreting musk gland. Based on morphological observation, epithelial cells of musk gland were isolated and cultured in vitro. After the third passage, the musk gland-derived cells were filled with many lipid droplets and proliferated well. We used gas chromatography and mass spectrometry to explore the chemical composition of lipid droplets in the musk gland-derived cells. The main components of secreted lipid droplet were alkanes, esters, amines, alcohols, ketones, organic acids, and aldehydes. Muscone, which is the main active compound of musk, was not found. This is a new attempt in the field of animal musk to obtain naturally secreted animal musk in vitro by cloning specialized cells. In conclusion, this study provides a reference at the cellular level to further analyze the biology and physiology of the musk gland epithelium and secretion mechanism of musk deer.


Assuntos
Estruturas Animais/citologia , Separação Celular/métodos , Forma Celular , Cervos/anatomia & histologia , Células Epiteliais/citologia , Epitélio/metabolismo , Ácidos Graxos Monoinsaturados/química , Estruturas Animais/anatomia & histologia , Animais , Cruzamento , Células Cultivadas , Florestas , Cromatografia Gasosa-Espectrometria de Massas , Estações do Ano
19.
BMC Evol Biol ; 18(1): 92, 2018 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-29898669

RESUMO

BACKGROUND: Cyclostome bryozoans are an ancient group of marine colonial suspension-feeders comprising approximately 700 extant species. Previous morphological studies are mainly restricted to skeletal characters whereas data on soft tissues obtained by state-of-the-art methods are still lacking. In order to contribute to issues related to cyclostome ground pattern reconstruction, we analyzed the morphology of the neuromuscular system Cinctipora elegans by means of immunocytochemical staining, confocal laser scanning microscopy, histological sections and microCT imaging. RESULTS: Polypides of C. elegans are located in elongated tubular skeletal cystids. Distally, the orifice leads into a prominent vestibulum which is lined by an epithelium that joins an almost complete perimetrical attachment organ, both containing radially arranged neurite bundles and muscles. Centrally, the prominent atrial sphincter separates the vestibulum from the atrium. The latter is enclosed by the tentacle sheath which contains few longitudinal muscle fibers and two principal neurite bundles. These emerge from the cerebral ganglion, which is located at the lophophoral base. Lateral ganglia are located next to the cerebral ganglion from which the visceral neurite bundles emerge that extend proximally towards the foregut. There are four tentacle neurite bundles that emerge from the ganglia and the circum-oral nerve ring, which encompasses the pharynx. The tentacles possess two striated longitudinal muscles. Short buccal dilatators are situated at the lophophoral base and short muscular sets are present at the abfrontal and frontal side of the tentacle base. The pharynx is myoepithelial and triradiate in cross-section. Oocytes are found inside the pharyngeal myoepithelium. The digestive tract contains dense circular musculature and few longitudinal muscles. The membranous sac contains regular, thin, circular and diagonal muscles and neurites in its epithelial lining. CONCLUSIONS: The general structure of the neuro-muscular system is more reminiscent of the condition found in Gymnolaemata rather than Phylactolaemata, which supports a close relationship between Cyclostomata and Gymnolaemata. Several characters of C. elegans such as the lateral ganglia or loss of the cardia are probably apomorphic for this species. For the first time, oocytes that surprisingly develop in the pharyngeal wall are reported for this species.


Assuntos
Briozoários/anatomia & histologia , Briozoários/fisiologia , Músculos/anatomia & histologia , Sistema Nervoso/anatomia & histologia , Estruturas Animais/anatomia & histologia , Estruturas Animais/inervação , Animais , Trato Gastrointestinal/anatomia & histologia , Microscopia Confocal , Oócitos/citologia , Reprodução/fisiologia , Serotonina/metabolismo , Microtomografia por Raio-X
20.
Bioinspir Biomim ; 13(4): 046007, 2018 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-29848791

RESUMO

Aquatic Anisopteran dragonfly larvae achieve respiration and propulsion by repetitive water jets flowing through their anal openings. Previous studies have shown that the tri-leaflet anal valves modulate the emerging jet by varying the opening size. We discovered that the valves are also capable of controlling the opening asymmetry by independent retraction of a leaflet. This study shows the effects of their valve asymmetry control on the respiratory and propulsive flows. Furthermore, the effects of size variation are re-evaluated using fluid momentum and power equations. Synchronized dual cameras recorded the valve movement and the flow generated by Aeshnidae sp. During the respiratory jetting, retraction of a single leaflet positions the opening in an off-centred locale, from which diagonally deflected jets emerge. The resulting flow field, together with the opening size modulation, implicates a reduction in the reinhalation of the exhaled jet and partial powering of the refilling process. Instead, during the propulsive jetting, concurrent partial retraction of the three leaflets results in the centred opening. The resulting jet flows straight, which has an implication for lowering form drag. Additionally, the propulsive aperture size control suggests improved thrust production. Our study highlights the significant influence that an asymmetrically positioned jet opening can have on biological jet flow. The findings inspire a new mechanism for jet vectoring that may prove useful for application in the broader engineering field.


Assuntos
Odonatos/fisiologia , Natação/fisiologia , Canal Anal/anatomia & histologia , Canal Anal/fisiologia , Estruturas Animais/anatomia & histologia , Estruturas Animais/fisiologia , Animais , Fenômenos Biomecânicos , Biomimética , Hidrodinâmica , Larva/anatomia & histologia , Larva/fisiologia , Microscopia Confocal , Modelos Biológicos , Odonatos/anatomia & histologia , Reologia
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