Добірка наукової літератури з теми "Oenocyte"
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Статті в журналах з теми "Oenocyte":
1
Elstob, P. R., V. Brodu, and A. P. Gould. "spalt-dependent switching between two cell fates that are induced by the Drosophila EGF receptor." Development 128, no. 5 (March 1, 2001): 723–32. http://dx.doi.org/10.1242/dev.128.5.723.
Анотація:
Signaling from the EGF receptor (EGFR) can trigger the differentiation of a wide variety of cell types in many animal species. We have explored the mechanisms that generate this diversity using the Drosophila peripheral nervous system. In this context, Spitz (SPI) ligand can induce two alternative cell fates from the dorsolateral ectoderm: chordotonal sensory organs and non-neural oenocytes. We show that the overall number of both cell types that are induced is controlled by the degree of EGFR signaling. In addition, the spalt (sal) gene is identified as a critical component of the oenocyte/chordotonal fate switch. Genetic and expression analyses indicate that the SAL zinc-finger protein promotes oenocyte formation and supresses chordotonal organ induction by acting both downstream and in parallel to the EGFR. To explain these findings, we propose a prime-and-respond model. Here, sal functions prior to signaling as a necessary but not sufficient component of the oenocyte prepattern that also serves to raise the apparent threshold for induction by SPI. Subsequently, sal-dependent SAL upregulation is triggered as part of the oenocyte-specific EGFR response. Thus, a combination of SAL in the responding nucleus and increased SPI ligand production sets the binary cell-fate switch in favour of oenocytes. Together, these studies help to explain how one generic signaling pathway can trigger the differentiation of two distinct cell types.
2
Poidevin, Mickael, Nicolas Mazuras, Gwénaëlle Bontonou, Pierre Delamotte, Béatrice Denis, Maëlle Devilliers, Perla Akiki, et al. "A fatty acid anabolic pathway in specialized-cells sustains a remote signal that controls egg activation in Drosophila." PLOS Genetics 20, no. 3 (March 14, 2024): e1011186. http://dx.doi.org/10.1371/journal.pgen.1011186.
Анотація:
Egg activation, representing the critical oocyte-to-embryo transition, provokes meiosis completion, modification of the vitelline membrane to prevent polyspermy, and translation of maternally provided mRNAs. This transition is triggered by a calcium signal induced by spermatozoon fertilization in most animal species, but not in insects. In Drosophila melanogaster, mature oocytes remain arrested at metaphase-I of meiosis and the calcium-dependent activation occurs while the oocyte moves through the genital tract. Here, we discovered that the oenocytes of fruitfly females are required for egg activation. Oenocytes, cells specialized in lipid-metabolism, are located beneath the abdominal cuticle. In adult flies, they synthesize the fatty acids (FAs) that are the precursors of cuticular hydrocarbons (CHCs), including pheromones. The oenocyte-targeted knockdown of a set of FA-anabolic enzymes, involved in very-long-chain fatty acid (VLCFA) synthesis, leads to a defect in egg activation. Given that some but not all of the identified enzymes are required for CHC/pheromone biogenesis, this putative VLCFA-dependent remote control may rely on an as-yet unidentified CHC or may function in parallel to CHC biogenesis. Additionally, we discovered that the most posterior ventral oenocyte cluster is in close proximity to the uterus. Since oocytes dissected from females deficient in this FA-anabolic pathway can be activated in vitro, this regulatory loop likely operates upstream of the calcium trigger. To our knowledge, our findings provide the first evidence that a physiological extra-genital signal remotely controls egg activation. Moreover, our study highlights a potential metabolic link between pheromone-mediated partner recognition and egg activation.
3
Zara, F. J., and F. H. Caetano. "Ultramorphology and histochemistry of fat body cells from last Instar larval of the Pachycondyla (=Neoponera) villosa (Fabricius) (Formicidae: Ponerinae)." Brazilian Journal of Biology 64, no. 3b (August 2004): 725–35. http://dx.doi.org/10.1590/s1519-69842004000400022.
Анотація:
The fat body cells of Pachycondyla (=Neoponera) villosa are disposed in a single layer between the cuticle and the digestive tract, forming a group of cells enclosed by a thin membrane. Histological studies have revealed three different cellular types: trophocyte (more abundant), urate, (located among the trophocytes), and oenocyte (the scarcest), usually observed laying near the cuticle. Histochemically, the trophocytes showed a positive reaction for basic proteins in the nucleus and cytoplasm, as well as a strong positive reaction in the cytoplasmic granules. The test for carbohydrates showed a strong positive reaction throughout the cytoplasm, while the test for lipids was positive for the cytoplasmic vesicles. The urate cells showed a positive reaction for basic proteins in the nucleus and in the areas of the cytoplasm surrounding the vesicles. These cells did not react to the PAS test or to Sudan Black B. The oenocytes showed a weak positive reaction to PAS and a strong positive reaction to Sudan Black B and Mercuric-bromophenol Blue.
4
Burns, Kevin A., Lisa M. Gutzwiller, Yoshinori Tomoyasu, and Brian Gebelein. "Oenocyte development in the red flour beetle Tribolium castaneum." Development Genes and Evolution 222, no. 2 (March 3, 2012): 77–88. http://dx.doi.org/10.1007/s00427-012-0390-z.
5
Brodu, Véronique, Philip R. Elstob, and Alex P. Gould. "abdominal A specifies one cell type in Drosophila by regulating one principal target gene." Development 129, no. 12 (June 15, 2002): 2957–63. http://dx.doi.org/10.1242/dev.129.12.2957.
Анотація:
The Hox/homeotic genes encode transcription factors that generate segmental diversity during Drosophila development. At the level of the whole animal, they are believed to carry out this role by regulating a large number of downstream genes. Here we address the unresolved issue of how many Hox target genes are sufficient to define the identity of a single cell. We focus on the larval oenocyte, which is restricted to the abdomen and induced in response to a non-cell autonomous, transient and highly selective input from abdominal A (abdA). We use Hox mutant rescue assays to demonstrate that this function of abdA can be reconstituted by providing Rhomboid (Rho), a processing factor for the EGF receptor ligand, secreted Spitz. Thus, in order to make an oenocyte, abdA regulates just one principal target, rho, that acts at the top of a complex hierarchy of cell-differentiation genes. These studies strongly suggest that, in at least some contexts, Hox genes directly control only a few functional targets within each nucleus. This raises the possibility that much of the overall Hox downstream complexity results from cascades of indirect regulation and cell-to-cell heterogeneity.
6
Cinnamon, Einat, Rami Makki, Annick Sawala, Leah P. Wickenberg, Gary J. Blomquist, Claus Tittiger, Ze'ev Paroush, and Alex P. Gould. "Drosophila Spidey/Kar Regulates Oenocyte Growth via PI3-Kinase Signaling." PLOS Genetics 12, no. 8 (August 8, 2016): e1006154. http://dx.doi.org/10.1371/journal.pgen.1006154.
7
Jaremek, Milena, Krzysztof Olszewski, Jacek Chobotow, and Aneta Strachecka. "The Morphological Image of Fat Body and Tergal Gland Cells in Uninseminated Apis mellifera Queen Bees." Insects 15, no. 4 (April 3, 2024): 244. http://dx.doi.org/10.3390/insects15040244.
Анотація:
The morphological changes in fat body cells, tergal gland cells, and the surface areas of the cell nuclei were determined in queen bees of the subspecies Apis mellifera carnica. This study focused on 1-, 8-, and 20-day-old uninseminated females kept in colonies, analyzing cells from three locations in the abdomen: the sternite, and tergites III and V. The oenocytes in the sternites were large, oval/circular with a centrally located nucleus, while in tergites III and V, they were small and triangular in the 1-day-old queens. During the first week of life, these cells in tergites III and V change their shape to oval and increase their sizes. The initially light yellow and then dark yellow granularities in the oenocytes of the fat body appear along with the advancing age of the queens. The trophocytes (sternites, tergites III and V) in the 1-day-old queens were completely filled with droplets of different sizes. In the 8- and 20-day-old queens, the number and size of the droplets decreased in the trophocytes of tergites III and V. The tergal gland cells had a centrally located cell nucleus in the 1-, 8- and 20-day-old queens. The dark granularities in these cells were visible only in the 20-day-old queens. Different morphological images of the fat body at the sternite, and tergites III and V, and the difference in the size of the oenocyte cell nuclei may indicate various functions of the fat body depending on its location. Characterization of the changes in the morphology of the fat body, taking into account its segmental character, and the tergal glands requires further research in older queens, e.g., one-year-old, brooding queens.
8
Chiang, Yin Ning, Kah Junn Tan, Henry Chung, Oksana Lavrynenko, Andrej Shevchenko, and Joanne Y. Yew. "Steroid Hormone Signaling Is Essential for Pheromone Production and Oenocyte Survival." PLOS Genetics 12, no. 6 (June 22, 2016): e1006126. http://dx.doi.org/10.1371/journal.pgen.1006126.
9
Certel, K., M. G. Anderson, R. J. Shrigley, and W. A. Johnson. "Distinct variant DNA-binding sites determine cell-specific autoregulated expression of the Drosophila POU domain transcription factor drifter in midline glia or trachea." Molecular and Cellular Biology 16, no. 4 (April 1996): 1813–23. http://dx.doi.org/10.1128/mcb.16.4.1813.
Анотація:
Transcriptional regulators utilizing the POU domain DNA-binding motif have been shown to form multi-protein complexes dependent on the POU domain itself and its flexible recognition of various octamer sequence elements. We have identified two variant POU domain recognition elements DFRE1 and DFRE2, which are found within a 514-bp autoregulatory enhancer of the Drosophila melanogaster POU domain gene drifter (dfr). Both elements are capable of binding bacterially produced full-length DFR protein with high affinity, although they differ in the 5'-to-3' orientation of POU-specific and POU homeodomain subelements. When placed in dfr loss-of-function genetic backgrounds, all expression of dfr-lacZ fusion genes under control of the autoregulatory enhancer is dependent on DFR activity levels. However, the complete enhancer sequence directs beta-galactosidase expression in only a subset of cells which normally express the endogenous DFR protein, including the middle pair of midline glias of the ventral nerve cord, the oenocyte clusters, and all tracheal cells. In addition, DFRE1 and DFRE2 exhibit separable tissue-specific functions when independently disrupted or deleted. Disruption of DFRE1 function specifically abolishes beta-galactosidase expression in the middle pair of midline glias. Deletion of DFRE causes a specific loss of tracheal expression, leaving oenocyte and midline glia expression intact. These results suggest that dfr cell-specific autoregulation is determined by the context of DFR POU domain binding within the enhancer, which is possibly mediated by the formation of recognition element-specific heteromultimeric complexes containing additional tissue-specific factors.
10
Dweck, Hany K. M., Shimaa A. M. Ebrahim, Michael Thoma, Ahmed A. M. Mohamed, Ian W. Keesey, Federica Trona, Sofia Lavista-Llanos, et al. "Pheromones mediating copulation and attraction in Drosophila." Proceedings of the National Academy of Sciences 112, no. 21 (May 11, 2015): E2829—E2835. http://dx.doi.org/10.1073/pnas.1504527112.
Анотація:
Intraspecific olfactory signals known as pheromones play important roles in insect mating systems. In the model Drosophila melanogaster, a key part of the pheromone-detecting system has remained enigmatic through many years of research in terms of both its behavioral significance and its activating ligands. Here we show that Or47b-and Or88a-expressing olfactory sensory neurons (OSNs) detect the fly-produced odorants methyl laurate (ML), methyl myristate, and methyl palmitate. Fruitless (fruM)-positive Or47b-expressing OSNs detect ML exclusively, and Or47b- and Or47b-expressing OSNs are required for optimal male copulation behavior. In addition, activation of Or47b-expressing OSNs in the male is sufficient to provide a competitive mating advantage. We further find that the vigorous male courtship displayed toward oenocyte-less flies is attributed to an oenocyte-independent sustained production of the Or47b ligand, ML. In addition, we reveal that Or88a-expressing OSNs respond to all three compounds, and that these neurons are necessary and sufficient for attraction behavior in both males and females. Beyond the OSN level, information regarding the three fly odorants is transferred from the antennal lobe to higher brain centers in two dedicated neural lines. Finally, we find that both Or47b- and Or88a-based systems and their ligands are remarkably conserved over a number of drosophilid species. Taken together, our results close a significant gap in the understanding of the olfactory background to Drosophila mating and attraction behavior; while reproductive isolation barriers between species are created mainly by species-specific signals, the mating enhancing signal in several Drosophila species is conserved.
Дисертації з теми "Oenocyte":
1
Gutierrez, Eugenio. "Cellular and molecular studies of larval oenocyte function in Drosophila." Thesis, University College London (University of London), 2004. http://discovery.ucl.ac.uk/1446603/.
Анотація:
Lipid metabolism is regulated according to the nutritional status of the body and its energy demands. In vertebrates, the liver plays a central and multifunctional role in this process. Within hepatocytes, lipid metabolites of cytochrome P450-4 (Cyp4) enzymes serve to activate Peroxisome Proliferator-Activated Receptors (PPARs), leading to the induction of a myriad of genes involved in lipid uptake, processing and degradation. In principle, the insect Drosophila should provide a genetic model for studying these processes but several aspects of lipid metabolism, including the identity of the cell-types that fulfil the functions of the vertebrate liver are not yet clear. The larval oenocytes of insects are large lipid-laden cells whose function has been a matter of considerable debate over the last hundred and fifty years. Three longstanding hypotheses are that oenocytes regulate tracheal respiration, hemolymph composition or aspects of moulting. To begin to test these hypotheses, I have used enhancer traps and a large database of expression patterns to identify 35 genes selectively expressed in oenocytes. 17 of these encode products highly related to vertebrate liver proteins playing roles in the uptake, modification and degradation of lipids. These include two lipophorin receptors, a Cyp4 protein and 6 peroxisomal enzymes catabolising fatty acids by ?-oxidation. By using an optimised GAL4/UAS-reaper approach to ablate Drosophila oenocytes, I find that they are required for the completion of the moult from second- to-third larval instars. Arrested oenocyte-less larvae display duplicated exoskeletal elements, suppressed food intake and a premature wandering behaviour. These phenotypes are strikingly similar to those produced by mutations in the E75A variant of Ecdysone-induced protein 75B (Eip75B), an orthologue of vertebrate PPARs and one of the 35 oenocyte genes identified here. Together, these studies demonstrate that oenocytes possess much of the lipid-processing and regulatory circuitry of vertebrate hepatocytes and may use this machinery to trigger developmental transitions during larval life.
2
Poidevin, Mickaël. "La synthèse d'acides gras dans des cellules spécialisées agit à distance sur le processus d'activation des ovocytes chez la drosophile." Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPASL016.
Анотація:
Une étude statistique de l'organisation mondiale de la santé a révélé qu'un adulte sur six est concerné par des problèmes d'infertilité. Ce sujet majeur de nos sociétés est complexe, multifactoriel avec une évolution à l'échelle mondiale qui est difficile à évaluer. Il est donc essentiel de mener davantage de recherche pour mieux comprendre l'évolution de l'infertilité, mais aussi les mécanismes cellulaires et moléculaires conduisant à une bonne fertilité.Fortuitement, un crible génétique des enzymes responsables de la synthèse des acides gras dans des cellules spécialisées de la drosophile a déclenché un phénotype de stérilité. Ces cellules spécialisées que l'on nomme oenocytes sont essentielles aux métabolismes des acides gras et impliquées dans de nombreux processus tels que l'homéostasie lipidique, la protection contre la dessication et la communication phéromonale.Mes travaux montrent que la synthèse d'un ou plusieurs acides gras à très longue chaîne dans les oenocytes est indispensable à la fertilité des femelles et que le défaut de cette synthèse provoque une rétention des spermatozoïdes dans les organes de stockage, spermathèques et réceptacle séminal. J'ai montré que le phénotype de stérilité n'est pas lié à un défaut d'activité des spermatozoïdes et qu'ils fertilisent efficacement les ovocytes matures. En revanche mes résultats indiquent que les oeufs présentent un défaut d'activation empêchant leur développement.Chez les insectes l'activation de l'ovocyte mature qui permet le développement embryonnaire ne dépend pas de l'entrée du spermatozoïde comme chez les mammifères. Cette activation est déclenchée par un signal calcique lors du passage dans les voies génitales femelles. L'ensemble de mes résultats montrent pour la première fois qu'un signal lipidique extra-génital provoque l'activation des ovocytes matures permettant ainsi l'induction du développement embryonnaireA statistical study by the World Health Organization revealed that one adult over six is affected by infertility problems. This major social issue is complex and multifactorial, with worldwide trends that are difficult to assess. It is therefore essential to carry out more research to better understand not only the evolution of infertility, but also the cellular and molecular mechanisms leading to efficient fertility.Serendipitously, we discovered that a genetic screen to enzymes responsible for fatty acid synthesis in specialized Drosophila cells provoked a sterile phenotype. These specialized cells, called as oenocytes, are essential for fatty acid metabolism, and are involved in numerous processes, including lipid homeostasis, protection against desiccation and pheromonal communication.My work shows that the synthesis of one or more very long-chain fatty acids in oenocytes is essential for female fertility, and that a defect in this synthesis causes spermatozoa to be retaintion in the storage organs, spermathecae and seminal receptacle. I have shown that the sterility phenotype is not linked to a defect in sperm activity, and that sperm fertilize mature oocytes efficiently. On the other hand, my results indicate that the eggs show an activation defect preventing their development.In insects, activation of the mature oocyte, which leads to embryonic development, is not dependent on sperm entry as in mammals. This activation is triggered by a calcium signal while the oocyte moves through the female genital tract. Taken together, my results show for the first time that an extra-genital lipid-signal triggers the activation of mature oocytes, thus enabling the induction of embryonic development
3
Fouyer, Tony. "En métal et en céramique : production, imitation, circulation des œnochoés « rhodiennes » entre l’Italie, la Méditerranée et les communautés nord-alpines." Thesis, Bourgogne Franche-Comté, 2019. http://www.theses.fr/2019UBFCH036.
Анотація:
Il n’existe pas, à l’heure actuelle, d’étude prenant en compte trois classes de récipients, dans différents matériaux et sur un espace géographique aussi vaste. Il est en effet, nécessaire de mettre en relation les différentes productions de ces classes de vases, des prototypes aux imitations locales, afin d’appréhender le rôle de ces produits dans des contextes similaires ou différents. L’objectif est d’aborder à partir de différents aspects les contacts entre l’Italie, la Méditerranée et les communautés nord alpines :- tout d’abord à partir des productions et des aspects techniques,- puis par l’identification et l’étude approfondie des imitations locales de ces trois classes de récipients,- ensuite par la circulation des objets importés (voies et nature des échanges),- et enfin en clarifiant la place et le rôle des modèles importés et de leurs imitations au sein des contextes de découvertes et pour les clients.L’intérêt de cette thèse est de restituer un cadre complet et structuré des relations reliant le monde transalpin et les mondes grecs et étrusco-italiques à travers l’inventaire de trois classes de vases dont les fonctions rituelles et idéologiques sont intimement liées à leur utilisation dans le cadre du banquet d’origine gréco-méditerranéenne, dans laquelle l’interdisciplinarité est essentielle (archéologie classique, archéologie protohistorique et étruscologie). Il s’agit, à partir d’un autre point de vue sur les objets et sur les contextes de découverte, d’apporter des éléments de réponse en ce qui concerne les pratiques fonctionnelles, rituelles et idéologiques liées à ces objets qui sont rares et précieux, qu’ils soient importés ou réalisés in situ (acquérant de la valeur grâce à la technique de fabrication ou encore au caractère exotique auquel ils renvoient)At present there is no study taking into account three classes of containers, in different materials and in such a vast geographical area. It is necessary to relate the different productions of these classes of vases, from prototypes to local imitations, in order to understand the role of these products in similar or different contexts. The objective is to approach the contacts between Italy, the Mediterranean and the northern Alpine communities from different aspects:- first of all from the productions and the technical aspects,- then by the identification and in-depth study of the local imitations of these three classes of receptacles,- second, by the circulation of imported objects (routes and nature of trade);- and finally clarifying the role and role of imported models and their imitations in the contexts of discovery and for customers.The interest of this thesis is to restore a complete and structured framework of the relations linking the transalpine world and the Greek and Etrusco-italic worlds through the inventory of three classes of vases whose ritual and ideological functions are intimately linked to their use in the framework of the banquet of Greco-Mediterranean origin, in which interdisciplinarity is essential (classical archeology, protohistoric archeology and etruscology). From another perspective on objects and contexts of discovery, it is a question of providing answers about the functional, ritual and ideological practices associated with these objects which are rare and whether they are imported or made in situ (acquiring value through manufacturing technology or the exotic nature to which they refer)
Частини книг з теми "Oenocyte":
1
"oenocyte, n." In Oxford English Dictionary. 3rd ed. Oxford University Press, 2023. http://dx.doi.org/10.1093/oed/8687992645.
2
"Oenocytes." In Encyclopedia of Genetics, Genomics, Proteomics and Informatics, 1388. Dordrecht: Springer Netherlands, 2008. http://dx.doi.org/10.1007/978-1-4020-6754-9_11776.
3
"Oenochoe." In Encyclopedic Dictionary of Archaeology, 961. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-58292-0_150057.
4
"oenochoe, n." In Oxford English Dictionary. 3rd ed. Oxford University Press, 2023. http://dx.doi.org/10.1093/oed/5472597584.
5
"XI. The Fat Body, Urate Cells, and Oenocytes." In Anatomy of the Honey Bee, 217–26. Cornell University Press, 2018. http://dx.doi.org/10.7591/9781501717925-013.