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1.
Microsc Res Tech ; 84(9): 1977-1991, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33720486

RESUMO

The current observations focused on the ultrastructure comparison between the tongue of two reptile species endemic the Egyptian fauna; Bosc's fringe-toed lizard Acanthodactylus boskianus and Sinai fan-fingered gecko Ptyodactylus guttatus to exhibit the relationship between the lingual epithelium and its function according to their specific feeding strategy. A. boskianus possessed triangular elongated tongue with bifurcated tapering apex and wide base while; the P. guttatus had a triangular flattened tongue with conical shallow bifurcated apex and broad base. The ventral surface of the lingual apex of A. boskianus had transverse while in P. guttatus had two oval pads and median ventral groove. Both surfaces of the tongue of both examined species are covered by stratified squamous epithelium with great variability of degree of keratinization. The dorsal epithelium formed flattened and conical filiform papillae in A. boskianus, while in P. guttatus formed cylindrical papillae, conical, and tall filiform ones. Few taste buds are observed on the fore-tongue but increase on the mid-tongue of A. boskianus, while in P. guttatus, numerous taste buds are distributed on the fore-tongue and mid-tongue. Both surfaces of the laryngeal mound of both examined species provided with numerous of cilia and orifices of laryngeal gland. The present results confirmed that the tongue of A. boskianus acts as a chemoreceptor organ to follow pheromone trails of prey and mates. While in P. guttatus the tongue may play an important role in the feeding mechanism and act as a chemoreceptor organ.


Assuntos
Lagartos , Papilas Gustativas , Animais , Egito , Microscopia Eletrônica de Varredura , Língua
2.
Biosci Biotechnol Biochem ; 81(11): 2086-2089, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28831846

RESUMO

A novel anti-mollusk conopeptide pn4c was isolated from the Conus pennaceus venom by repeated HPLC fractionation based on the activity against freshwater snails. The primary structure of pn4c was determined by the mass spectrometric de novo sequencing analysis. In addition, pn3a was isolated from the same fraction containing pn4c, as a peptide with unknown functions.


Assuntos
Caramujo Conus/química , Peptídeos/química , Peptídeos/isolamento & purificação , Peçonhas/química , Sequência de Aminoácidos , Animais , Peptídeos/metabolismo
3.
Mar Genomics ; 34: 39-45, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28385518

RESUMO

The gymnosome (unshelled) pteropod Clione limacina is a pelagic predatory mollusc found in polar and sub-polar regions. It has been studied for its distinctive swimming behavior and as an obligate predator on the closely related thecosome (shelled) pteropods. As concern about ocean acidification increases, it becomes useful to compare the physiological responses of closely-related calcifying and non-calcifying species to acidification. The goals of this study were thus to generate a reference transcriptome for Clione limacina, to expose individuals to CO2 for a period of 3days, and to explore differential patterns of gene expression. Our Trinity assembly contained 300,994 transcripts of which ~26% could be annotated. In total, only 41 transcripts were differentially expressed following the CO2 treatment, consistent with a limited physiological response of this species to short-term CO2 exposure. The differentially expressed genes identified in our study were largely distinct from those identified in previous studies of thecosome pteropods, although some similar transcripts were identified, suggesting that comparison of these transcriptomes and responses may provide insight into differences in responses to ocean acidification among phylogenetically and functionally distinct molluscan lineages.


Assuntos
Dióxido de Carbono/metabolismo , Clione/genética , Clione/metabolismo , Transcriptoma , Animais , Concentração de Íons de Hidrogênio , Água do Mar/química
4.
Biosci Biotechnol Biochem ; 80(10): 1879-82, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27095279

RESUMO

Over 200 components with molecular mass ranging mainly from 400 to 4000 Da were characterized from the venom of the vermivorous cone snail Conus fulgetrum that inhabit Egyptian Red Sea. One major component having a molecular mass of 2946 Da was purified by HPLC, and its primary structure was determined by a combination of Edman degradation and MS/MS analysis.


Assuntos
Caramujo Conus/química , Peçonhas/química , Sequência de Aminoácidos , Animais , Peso Molecular , Fragmentos de Peptídeos/química
5.
BMC Evol Biol ; 14(1): 44, 2014 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-24612655

RESUMO

BACKGROUND: The phylogenetic relationships of many taxa remain poorly known because of a lack of appropriate data and/or analyses. Despite substantial recent advances, amphibian phylogeny remains poorly resolved in many instances. The phylogenetic relationships of the Ethiopian endemic monotypic genus Ericabatrachus has been addressed thus far only with phenotypic data and remains contentious. RESULTS: We obtained fresh samples of the now rare and Critically Endangered Ericabatrachus baleensis and generated DNA sequences for two mitochondrial and four nuclear genes. Analyses of these new data using de novo and constrained-tree phylogenetic reconstructions strongly support a close relationship between Ericabatrachus and Petropedetes, and allow us to reject previously proposed alternative hypotheses of a close relationship with cacosternines or Phrynobatrachus. CONCLUSIONS: We discuss the implications of our results for the taxonomy, biogeography and conservation of E. baleensis, and suggest a two-tiered approach to the inclusion and analyses of new data in order to assess the phylogenetic relationships of previously unsampled taxa. Such approaches will be important in the future given the increasing availability of relevant mega-alignments and potential framework phylogenies.


Assuntos
Anuros/classificação , Anuros/genética , Evolução Biológica , Animais , Espécies em Perigo de Extinção , Filogeografia , Análise de Sequência de DNA
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