Academic literature on the topic 'Hormonas juveniles'
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Journal articles on the topic "Hormonas juveniles"
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Herrera-Ulloa, Angel, Jonathan Chacón-Guzmán, Gerando Zúñiga-Calero, Oscar Fajardo, and Ricardo Jiménez-Montealegre. "ACUICULTURA DE PARGO LA MANCHA LUTJANUS GUTTATUS (STEINDACHNER, 1869) EN COSTA RICA DENTRO DE UN ENFOQUE ECOSISTÉMICO." Revista Ciencias Marinas y Costeras 1 (December 21, 2009): 197. http://dx.doi.org/10.15359/revmar.1.11.
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La sobreexplotación pesquera y la búsqueda de alternativas ante la pobreza crónica han llevado a explorar el campo de la maricultura por medio de un enfoque ecosistémico se abrieron dos procesos paralelos: una estrategia e; investigación en laboratorio para el levantamiento larval de peces marinos tropicales y una estrategia de comanejo para desarrollar el cultivo de peces marinos tropicales. El pargo la mancha muestra gran potencial de producción de larvas y posterior cultivo en el mar. No mostró respuestas positivas a la inducción por medio de hormonas, el desarrollo de un ambiente adecuado para su reproducción espontánea, permitió tener desoves frecuentes y de calidad. La fase de levantamiento larval mostró contratiempos por el tamaño reducido de las larvas de pargo la mancha el manejo en tanques apropiados y el uso de enriquecedores permitieran mejorar los procesos y llegar a incrementar la producción de alevines. El enfoque ecosistémico permitió abrir los espacios necesarios que permitieron la operación de un proyecto piloto. La granja se creó con un enfoque productivo, pero también para turismo rural.Overfishing and the search for alternatives to it, led us to the explore mariculture as an option using an ecosystem-based approach through two parallel processes: an in-laboratory research strategy for larval rearing of tropical marine fish, and a strategy of co-management to develop tropical marine fish aquaculture. The spotted rose snapper shows great potential for larvae production and cage culture. This species showed no responses to hormone induction; however, the set up of a suitable environment allowed frequent, high-quality spontaneous spawnings. The larval rearing phase presented problems due to the small size of the larvae; although, management in appropriate tanks and the use of enrichments improved the processes, increasing the production of juveniles. This ecosystem approach allowed the operation of a profitable farm pilot project with a productive approach, but with rural tourism in mind as well.
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Boogert, Neeltje J., Robert F. Lachlan, Karen A. Spencer, Christopher N. Templeton, and Damien R. Farine. "Stress hormones, social associations and song learning in zebra finches." Philosophical Transactions of the Royal Society B: Biological Sciences 373, no. 1756 (August 13, 2018): 20170290. http://dx.doi.org/10.1098/rstb.2017.0290.
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The use of information provided by others is a common short-cut adopted to inform decision-making. However, instead of indiscriminately copying others, animals are often selective in what, when and whom they copy. How do they decide which ‘social learning strategy’ to use? Previous research indicates that stress hormone exposure in early life may be important: while juvenile zebra finches copied their parents' behaviour when solving novel foraging tasks, those exposed to elevated levels of corticosterone (CORT) during development copied only unrelated adults. Here, we tested whether this switch in social learning strategy generalizes to vocal learning. In zebra finches, juvenile males often copy their father's song; would CORT-treated juveniles in free-flying aviaries switch to copying songs of other males? We found that CORT-treated juveniles copied their father's song less accurately as compared to control juveniles. We hypothesized that this could be due to having weaker social foraging associations with their fathers, and found that sons that spent less time foraging with their fathers produced less similar songs. Our findings are in line with a novel hypothesis linking early-life stress and social learning: early-life CORT exposure may affect social learning indirectly as a result of the way it shapes social affiliations. This article is part of the theme issue ‘Causes and consequences of individual differences in cognitive abilities’.
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Meeran, Dawud, Henryk F. Urbanski, Susan J. Gregory, Julie Townsend, and Domingo J. Tortonese. "Developmental Changes in the Hormonal Identity of Gonadotroph Cells in the Rhesus Monkey Pituitary Gland." Journal of Clinical Endocrinology & Metabolism 88, no. 6 (June 1, 2003): 2934–42. http://dx.doi.org/10.1210/jc.2002-021001.
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To help elucidate the regulatory mechanism responsible for divergent gonadotrophin secretion during sexual maturation, we examined the gonadotroph population and hormonal identity of gonadotroph subtypes in pituitary glands of juvenile (age, 1.7 ± 0.2 yr) and adult (age, 12.3 ± 0.8 yr) male rhesus monkeys (Macacca mulatta). Serum LH and testosterone concentrations were, respectively, 3 and 7 times lower in juveniles than in adults, thus confirming the different stages of development. Immunohistochemistry revealed that the proportion of LH gonadotrophs in relation to the total pituitary cell population in the juvenile animals was significantly smaller than in the adults. In a subsequent study, double immunofluorescent labeling identified three distinct gonadotroph subtypes in both age groups: ones expressing either LH or FSH and another one expressing a combination of both gonadotrophins. Whereas the number of monohormonal LH cells per unit area was greater in the adults than in the juveniles, the number of monohormonal FSH gonadotrophs was remarkably lower. However, the proportion of FSH cells (whether mono- or bihormonal) within the gonadotroph population was similar between groups. Interestingly, the proportion and number of bihormonal gonadotrophs as well as the LH/FSH gonadotroph ratio were significantly greater in the adults than in the juveniles. Taken together, these data reveal that during the juvenile-adult transition period, not only does the pituitary gonadotroph population increase, but a large number of monohormonal FSH gonadotrophs are likely to become bihormonal. Because this morphological switch occurs when marked changes in plasma gonadotrophins are known to occur, it may represent an intrapituitary mechanism that differentially regulates gonadotrophin secretion during sexual development.
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Nunes, Scott, Eva-Maria Muecke, and Kay E. Holekamp. "Seasonal effects of food provisioning on body fat, insulin, and corticosterone in free-living juvenile Belding's ground squirrels (Spermophilus beldingi)." Canadian Journal of Zoology 80, no. 2 (February 1, 2002): 366–71. http://dx.doi.org/10.1139/z01-222.
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We evaluated the relationship between body fat and the metabolic hormones insulin and corticosterone in free-living juvenile Belding's ground squirrels (Spermophilus beldingi). Some free-living juveniles were provisioned with extra food high in fat and calories, and unprovisioned juveniles were used as controls. Body fat (as a percentage of body mass) of squirrels was regularly evaluated using non-invasive methods. Blood samples were also regularly collected from juveniles and assayed for plasma concentrations of insulin and corticosterone. Provisioned juveniles were fatter than unprovisioned juveniles during most of the active season, but differences in body fat disappeared near the end of summer as juveniles began fattening for hibernation. Thus, our data indicate that although body fat may fluctuate with energy availability early in the active season, it is regulated at precise levels as squirrels prepare for winter. Plasma corticosterone concentrations did not differ between provisioned and unprovisioned juveniles. However, plasma insulin concentrations were greater in provisioned than in unprovisioned juveniles early in the summer. Differences in insulin concentrations disappeared later in the active season, just prior to the disappearance of differences in body fat. Moreover, plasma insulin concentrations were significantly correlated with subsequent changes in body fat. Thus, our data suggest a link between insulin and seasonal regulation of body fat in juvenile S. beldingi.
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PETER, F. "Juvenile thyrotoxicosis." Acta Endocrinologica 113, no. 4_Suppl (December 1986): S361—S366. http://dx.doi.org/10.1530/acta.0.112s361.
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ABSTRACT The incidence of juvenile thyrotoxicosis has not exceeded one case per 100,000 population per year in Hungary during the past decades. From more than 200 simultaneous determinations of serum thyroid hormones (T3, T4, FT4) it was concluded that increased FT4 concentrations are the most frequent findings in thyrotoxicosis, even when both or one of the other thyroid hormone concentrations (T3, T4) are normal,-TSH and prolactin responses to TRH were studied in 18 patients; TSH remained always undetectable whereas prolactin increased in half of the patients. A significant negative relationship was found between the prolactin response and the level of circulating thyroid hormone. Although the pituitary lactotrophin is controlled by thyroid hormones, thyrotrophin is more sensitive to thyroid hormone levels in juvenile thyrotoxicosis.-In 56 TRH tests during antithyroid drug therapy this test was not found to be useful in predicting the likelihood of long-term remission. - The low maintenance dose of antithyroid treatment (2.5-5.0 mg/day) without thyroid hormone addition seems to be a favourable mode of therapy in juvenile thyrotoxicosis.
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Chatrath, Ritu, Karen L. Ronningen, Peter LaBreche, Sandra R. Severson, Muthuvel Jayachandran, Margarita P. Bracamonte, and Virginia M. Miller. "Effect of puberty on coronary arteries from female pigs." Journal of Applied Physiology 95, no. 4 (October 2003): 1672–80. http://dx.doi.org/10.1152/japplphysiol.00099.2003.
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Vascular function changes following loss of ovarian hormones in women at menopause and in experimental animals following surgical ovariectomy. Little is known about changes in vascular function during hormonal transition from sexual immaturity (juvenile) to sexual maturity. Therefore, experiments were designed to determine effects of natural puberty on vascular function in female pigs. Tissue was studied from eight juvenile (2-3 mo) and eight adult (5-6 mo) female pigs. Plasma nitric oxide (NO) was measured, and mRNA for endothelium-derived NO synthase (eNOS) and eNOS protein were determined in aortic endothelial cells. Rings of coronary arteries were suspended for measurement of isometric force in organ chambers. Serum 17β-estradiol levels were comparable in the two groups, whereas the arithmetic mean of progesterone levels was about two-thirds lower in adults compared with juvenile pigs. Plasma NO was significantly higher in juveniles compared with adults, but mRNA and protein for eNOS were comparable. In coronary arteries, an α2-adrenergic agonist caused greater endothelium-dependent relaxations in rings from juvenile compared with adult pigs. Relaxations to bradykinin were similar in arteries from both groups, but inhibition of NO reduced relaxations only in arteries from juvenile pigs. Relaxations from NO were greater in arteries from adult compared with juvenile female pigs. In conclusion, coronary arterial endothelial and smooth muscle responses are selectively modulated at puberty in female pigs. At maturity, plasma NO is reduced and sensitivity of the smooth muscle to exogenous NO is increased. Posttranscriptional regulation of eNOS protein may explain differences in NO bioavailability in juvenile pigs.
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Tibbetts, Elizabeth A., Katherine Crocker, and Zachary Y. Huang. "Socially selected ornaments influence hormone titers of signalers and receivers." Proceedings of the National Academy of Sciences 113, no. 30 (July 8, 2016): 8478–83. http://dx.doi.org/10.1073/pnas.1602707113.
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Decades of behavioral endocrinology research have shown that hormones and behavior have a bidirectional relationship; hormones both influence and respond to social behavior. In contrast, hormones are often thought to have a unidirectional relationship with ornaments. Hormones influence ornament development, but little empirical work has tested how ornaments influence hormones throughout life. Here, we experimentally alter a visual signal of fighting ability in Polistes dominulus paper wasps and measure the behavioral and hormonal consequences of signal alteration in signalers and receivers. We find wasps that signal inaccurately high fighting ability receive more aggression than controls and receiving aggression reduces juvenile hormone (JH) titers. As a result, immediately after contests, inaccurate signalers have lower JH titers than controls. Ornaments also directly influence rival JH titers. Three hours after contests, wasps who interacted with rivals signaling high fighting ability have higher JH titers than wasps who interacted with rivals signaling low fighting ability. Therefore, ornaments influence hormone titers of both signalers and receivers. We demonstrate that relationships between hormones and ornaments are flexible and bidirectional rather than static and unidirectional. Dynamic relationships among ornaments, behavior, and physiology may be an important, but overlooked factor in the evolution of honest communication.
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Oi, Cintia Akemi, Helena Mendes Ferreira, Rafael Carvalho da Silva, Andreas Bienstman, Fabio Santos do Nascimento, and Tom Wenseleers. "Effects of juvenile hormone in fertility and fertility-signaling in workers of the common wasp Vespula vulgaris." PLOS ONE 16, no. 5 (May 17, 2021): e0250720. http://dx.doi.org/10.1371/journal.pone.0250720.
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In the highly eusocial wasp, Vespula vulgaris, queens produce honest signals to alert their subordinate workers of their fertility status, and therefore they are reproductively suppressed and help in the colony. The honesty of the queen signals is likely maintained due to hormonal regulation, which affects fertility and fertility cue expression. Here, we tested if hormonal pleiotropy could support the hypothesis that juvenile hormone controls fertility and fertility signaling in workers. In addition, we aimed to check oocyte size as a proxy of fertility. To do that, we treated V. vulgaris workers with synthetic versions of juvenile hormone (JH) analogue and a JH inhibitor, methoprene and precocene, respectively. We dissected the treated females to check ovary activation and analyzed their chemical profile. Our results showed that juvenile hormone has an influence on the abundance of fertility linked compounds produced by workers, and it also showed to increase oocyte size in workers. Our results corroborate the hypothesis that juvenile hormone controls fertility and fertility signaling in workers, whereby workers are unable to reproduce without alerting other colony members of their fertility. This provides supports the hypothesis that hormonal pleiotropy contributes to keeping the queen fertility signals honest.
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Siregar, Khoirotun Nisa, Fajar Maulana, Muhammad Zairin Jr., Alimuddin Alimuddin, and Widanarni Widanarni. "Controlling the cannibalism of African catfish juvenile by 17β‒estradiol hormone administration and the stocking density determination." Jurnal Akuakultur Indonesia 20, no. 1 (June 9, 2021): 72–81. http://dx.doi.org/10.19027/jai.20.1.72-81.
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An effort to increase the production of juvenile catfish is limited by the high mortality rate, especially caused by cannibalism. The hormonal treatment has been conducted as an effort to control cannibalism. This study used completely randomized factorial design, consisted of six treatments and three replications. There were two factors examined in this study, the first factor was different doses of 17β‒estradiol hormone (0, 30, and 60 mg estradiol‒17β/kg) incorporated in the feed, and the second factor was stocking density (150 and 300 fish/m2). Juvenile catfish with the size of 4.0 ± 0.1 cm were reared for 30 days in the 84 L aquarium. The results showed that hormone treatment could reduce cannibalism rate, type-I and II cannibalism compared to control (P<0.05). The results showed that the lowest of mortality was obtained in the treatment B (17β‒estradiol administration of 30 mg/kg, at stocking density of 150 fish/m2; P<0.05). The lowest cortisol level was found in treatment F, and the highest estradiol level was found in treatment F (17β‒estradiol administration of 60 mg/kg, at stocking density of 300 fish/m2; P<0.05). The lowest of blood glucose level was found in treatment B (P<0.05). The highest specific weight growth was found in the stocking density of 150 fish/m2 (P<0.05). The results of this study indicated that administration of 17β‒estradiol in feed could reduce the level of cannibalism in African catfish juvenile.
Keywords: cannibalism, Juvenile, catfish, estradiol‒17β, cortisol
ABSTRAK
Upaya untuk meningkatkan produksi benih ikan lele dibatasi oleh tingginya angka kematian, terutama yang disebabkan oleh kanibalisme. Pendekatan hormonal telah dilakukan sebagai upaya pengendalian kanibalisme. Penelitian ini menggunakan rancangan acak lengkap faktorial, terdiri dari enam perlakuan dan tiga ulangan. Ada dua faktor yang diteliti dalam penelitian ini, faktor pertama adalah dosis hormon 17β‒estradiol yang berbeda (0, 30, dan 60 mg/kg) yang diberikan melalui pakan, dan faktor kedua adalah padat tebar (150 dan 300 ekor/m2). Benih ikan lele berukuran 4.0 ± 0.1 cm dipelihara selama 30 hari di akuarium (84 L). Hasil penelitian menunjukkan bahwa perlakuan hormon dapat menurunkan tingkat kanibalisme tipe‒I dan II dibandingkan kontrol (P<0.05). Hasil penelitian menunjukkan bahwa mortalitas terendah diperoleh pada perlakuan B (pemberian 17β‒estradiol 30 mg/kg, pada padat tebar 150 ekor/m2; P<0.05). Kadar kortisol terendah ditemukan pada perlakuan F, dan kadar estradiol tertinggi ditemukan pada perlakuan F (pemberian 17β‒estradiol 60 mg/kg, pada padat tebar 300 ekor/m2; P<0.05). Kadar glukosa darah terendah ditemukan pada perlakuan B (P<0.05). Pertumbuhan bobot spesifik tertinggi ditemukan pada padat tebar 150 ekor/m2 (P<0.05). Hasil penelitian ini menunjukkan bahwa pemberian hormon 17β‒estradiol dengan dosis 30 mg/kg pakan, dan padat tebar 150 ekor/m2 dapat menurunkan tingkat kanibalisme pada benih ikan lele di Afrika.
Kata kunci: kanibalisme, juvenil, lele, 17β‒estradiol, kortisol
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Jindra, Marek. "Where did the pupa come from? The timing of juvenile hormone signalling supports homology between stages of hemimetabolous and holometabolous insects." Philosophical Transactions of the Royal Society B: Biological Sciences 374, no. 1783 (August 26, 2019): 20190064. http://dx.doi.org/10.1098/rstb.2019.0064.
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Insect metamorphosis boasts spectacular cases of postembryonic development when juveniles undergo massive morphogenesis before attaining the adult form and function; in moths or flies the larvae do not even remotely resemble their adult parents. A selective advantage of complete metamorphosis (holometaboly) is that within one species the two forms with different lifestyles can exploit diverse habitats. It was the environmental adaptation and specialization of larvae, primarily the delay and internalization of wing development, that eventually required an intermediate stage that we call a pupa. It is a long-held and parsimonious hypothesis that the holometabolous pupa evolved through modification of a final juvenile stage of an ancestor developing through incomplete metamorphosis (hemimetaboly). Alternative hypotheses see the pupa as an equivalent of all hemimetabolous moulting cycles (instars) collapsed into one, and consider any preceding holometabolous larval instars free-living embryos stalled in development. Discoveries on juvenile hormone signalling that controls metamorphosis grant new support to the former hypothesis deriving the pupa from a final pre-adult stage. The timing of expression of genes that repress and promote adult development downstream of hormonal signals supports homology between postembryonic stages of hemimetabolous and holometabolous insects. This article is part of the theme issue ‘The evolution of complete metamorphosis’.
Dissertations / Theses on the topic "Hormonas juveniles"
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Abrisqueta, Carol Marc. "El receptor d'insulina com a element clau en la senyalització nutricional a la panerola Blattella germanica (L.) (Dictyoptera, Blattellidae)." Doctoral thesis, Universitat de Barcelona, 2013. http://hdl.handle.net/10803/127148.
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La panerola Blattella germanica és un insecte de metamorfosi incompleta (hemimetàbol) i anautògen. Aquesta és una estratègia reproductiva per la qual les femelles no es poden reproduir fins que no han menjat. D'alguna manera els senyals nutricionals han d'arribar als diferents teixits i cèl•lules per informar-los que s'ha assolit un estat nutricional adequat per iniciar els processos reproductius. Tant la via de TOR com la via del receptor d'insulina (InR) semblen formar part conjunta d'aquesta senyalització nutricional. A B. germanica la vitel•logènesi s'activa mitjançant l'hormona juvenil (HJ), que es fabrica i secreta per unes glàndules retrocerebrals anomenades corpora allata (CA). Quan falta l'aliment, els CA no sintetitzen HJ i aquesta no pot activar la síntesi de vitel•logenina (Vg) en el cos gras (CG), que no pot ser incorporada als ovaris, impedint que aquests es desenvolupin correctament.
Prèviament havia estat clonada la seqüència de TOR de B. germanica (BgTOR). En aquest treball s'han clonat les de BgInR, BgS6K i de BgPepck.
Gràcies al dsRNAi s'ha estudiat la funció del InR com a regulador del creixement, veient que no només afecta a la maduresa sexual de les femelles sinó també la seva mida quan s'injecta en estadis nimfals. La interferència del InR també produeix problemes en el correcte desenvolupament i desplegament de les ales i les tegmines. Així mateix, s'ha comprovat que la interferència del InR fa baixar els nivells dels trànscrits de HMG-S1, HMG-S2, HMG-R i epoxidasa en els CA, implicats en la síntesi d'HJ, així com de la Vg en CG , independentment de l'efecte de la HJ sobre aquesta. També s'ha vist que la interferència del InR produeix una major longevitat en les femelles, a causa que aquestes no es reprodueixen, evitant el desgast que això produeix. Alhora, l'aplicació de dsInR confereix certa protecció davant situacions de dejuni.
Altres resultats suggereixen que l'activació d'S6K, tal com succeeix en altres organismes, es realitza per modificacions post-transcripcionals, probablement per fosforilació de la proteïna. S'ha començat a posar a punt un sistema de western-blot per usar-lo per a la detecció de l'estat de fosforilació de S6K i per tant del seu estat d'activació. Mitjançant la tècnica del RNAi s'ha comprovat que la interferència per S6K fa baixar els transcrits de HMG-S1, HMGS2, HMG-R i epoxidasa en els CA, implicats en la síntesi d'HJ, així com la Vg en CG, indicant que està implicat en la transmissió del senyal nutricional als teixits implicats en la
vitel•logènesi.
Finalment s'ha establert Pepck com a marcador de l'estat nutricional, ja que s'incrementa la seva expressió en situacions de dejuni. No s'ha observat, però, que augmenti quan es redueixen els nivells de S6K o InR mitjançant RNAi, la qual cosa ens indica que la influència de la situació de dejuni sobre la transcripció de PEPCK es pot realitzar per vies alternatives a S6K i InR, si bé sembla que necessita de la presència de InR funcional.The cockroach Blatella germanica is a hemimetabolous insect with anautogenous reproduction. TOR and Insulin Receptor (InR) pathways are responsible of the nutritional signaling and to control reproductive processes. In B. germanica the yolk protein synthesis is activated by juvenile hormone (JH), which is secreted by retrocerebrals glands known as corpora allata (CA). In starvation, CA are not able to synthesize JH and it can’t activate the synthesis of vitelogenin (Vg) in the fat body (FB), and it can’t be incorporated by the ovaries, preventing their proper development. In this work we have cloned the sequences of BgInR, BgS6K and BgPepck. Using RNAi, InR has been studied as a regulator of growth, affecting not only sexual maturity of females, but also their size when RNAi is injected at nymphs. InR interference also produces problems for the proper development and deployment of wings and elytra. It has also been observed that InR interference lowers the levels of HMG-S1, HMG-S2, HMG-R and epoxidase transcription in CA, involved on the synthesis of JH by CA, and consequently, reducing Vg levels. Independently of JH, InR has a direct effect on Vg expression. Besides, InR interference confers greater longevity in females and protection in front of fasting. We have also begun to implement western-blot technique to detect phosphorylation of S6K. The S6K interference reduce transcription levels of HMG-S1, HMG-S2, HMG-R and epoxidase in CA, and Vg in the CG , indicating that it is involved in nutritional signal transmission to the tissues involved in vitelogenesis. Finally, we established Pepck as a marker of the nutritional status, as its expression is increased in starvation. However, it has not been observed any increase when reducing the levels of S6K or InR using RNAi, indicating that the influence of starvation on Pepck transcription can be performed in alternative ways to S6K and InR, but needs the presence of functional InR.
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Ureña, Sala Enric. "Regulació de la metamorfosi en insectes hemimetàbols i holometàbols. Caracterització funcional del gen E93 i del procés de sumoilació." Doctoral thesis, Universitat de Barcelona, 2013. http://hdl.handle.net/10803/129634.
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La maduració sexual dels animals està controlada per hormones. En els insectes alats aquesta maduració es coneix amb el nom de metamorfosi, i pot anar acompanyada d’una completa reorganització de la majoria d’òrgans i estructures juvenils (insectes holometàbols), o bé limitar-se a uns pocs teixits, principalment les ales i la genitàlia (insectes hemimetàbols). La metamorfosi dels insectes holometàbols (metamorfosi completa), que va aparèixer fa uns 300 milions d’anys a partir d’insectes hemimetàbols (metamorfosi incompleta), ha fet que aquest grup animal assolís un gran èxit evolutiu, ja que la diferent morfologia entre les formes juvenils i adultes els permet explotar hàbitats diferents i no competir entre elles. En tots els insectes els canvis metamòrfics estan controlats per dues hormones, la 20-hidroxiecdisona (20E) i l’hormona juvenil (HJ). La 20E s’encarrega d’induir les transicions entre les diverses mudes i estadis del desenvolupament, mentre que l’HJ modula la naturalesa d’aquestes transicions. La present tesi doctoral pretén aprofundir en el coneixement de la regulació molecular de la metamorfosi mitjançant l’estudi del procés de sumoilació, per una banda, i de la funció del gen E93 de l’altra. Per fer-ho s’han utilitzat tres models d’insectes: la panerola Blattella germanica (hemimetàbol), l’escarabat Tribolium castaneum (holometàbol basal) i la mosca Drosophila melanogaster (holometàbol modificat).
La sumoilació és una modificació posttraduccional que consisteix en la unió de manera reversible d’una proteïna petita, anomenada Sumo (de l’anglès Small Ubiquitin-like MOdifier), a una proteïna diana. Aquesta unió comporta la modificació de les propietats de la proteïna diana canviant-ne la conformació, la localització subcel•lular, la capacitat d’interacció amb altres proteïnes o la capacitat d’unió al DNA (en el cas dels factors de transcripció), entre d’altres. En els insectes, l’estudi del procés de sumoilació s’havia centrat fins ara en l’holometàbol D. melanogaster, on s’ha vist que és imprescindible per a l’inici de la metamorfosi. En aquesta tesi doctoral s’ha descrit la funció d’aquest procés en el desenvolupament postembrionari d’un insecte molt més basal, B. germanica. Aquesta panerola té dos paràlegs Sumo, BgSumo1 i BgSumo3, mentre que D. melanogaster en té tan sols un, Smt3. Aquest fet permetia, doncs, estudiar l’evolució funcional de la sumoilació en els insectes, i com aquesta funció està distribuïda en animals amb dos proteïnes Sumo. Així, mitjançant la tècnica de l’RNA d’interferència in vivo, s’ha comprovat que la sumoilació és essencial per a la supervivència durant el desenvolupament postembrionari de B. germanica. A més, s’ha vist que el paràleg BgSumo1 és necessari per a que es doni correctament la muda imaginal, per a la transducció del senyal de la 20E durant aquesta muda i per a la proliferació de l’epiteli fol•licular de l’oòcit basal. D’altra banda, s’ha comprovat que diversos receptors nuclears que conformen la via de senyalització de la 20E, imprescindible per a l’inici de la metamorfosi, són capaços de sumoilar-se en condicions in vitro.
La segona part del treball se centra en l’estudi funcional del factor de transcripció E93. Aquest, descrit prèviament en D. melanogaster com el responsable de la transmissió del senyal de la 20E en el procés de mort cel•lular programada durant la metamorfosi, s’ha comprovat en aquesta tesi que actua de regulador molt més general dels processos metamòrfics. Així, s’expressa fortament durant el període metamòrfic en els tres models estudiats (B. germanica, T. castaneum i D. melanogaster), i la seva absència bloqueja aquest procés. En l’hemimetàbol B. germanica, la manca de BgE93 durant el darrer estadi nimfal provoca la formació de nimfes supernumeràries, que mai assoleixen l’estadi adult. En l’holometàbol basal T. castaneum, per altra banda, l’absència de TcE93 impedeix la diferenciació adulta que es dóna durant la fase pupal i provoca la muda a un segon estadi pupal supernumerari. Finalment, en l’holometàbol modificat D. melanogaster també provoca un bloqueig general de la metamorfosi. A més, en aquests tres insectes E93 s’encarrega de reprimir l’expressió dels factors de transcripció Broad i Krüppel homolog-1, la presència dels quals impedeix la diferenciació adulta durant el darrer estadi juvenil dels insectes. Per tot això, aquest treball ha pogut descriure el factor de transcripció E93 com l’especificador adult dels insectes alats, pas essencial per avançar en el coneixement de la regulació de la metamorfosi i en l’estudi de l’aparició de la metamorfosi completa a partir d’insectes hemimetàbols.All immature animals undergo remarkable morphological and physiological changes to become mature adults. In winged insects, metamorphic changes are either limited to a few tissues (hemimetaboly) or involve a complete reorganization of most tissues and organs (holometaboly). In both cases, adult differentiation requires a temporally regulated balance between cell death, tissue growth and morphogenesis. Two hormones control this balance, the steroid 20-hydroxyecdysone (20E) and juvenile hormone (JH). The main goal of this thesis is to characterize the molecular mechanisms underlying the metamorphic process in insects through (i) the study of sumoylation and (ii) the functional characterization of the E93 transcription factor. To this aim, the hemimetabolous cockroach Blattella germanica, as well as the basal holometabolous beetle Tribolium castaneum and the highly modified holometabolous fly Drosophila melanogaster were used. Sumoylation is a post-translational modification that consists on the covalent binding of a small protein, called Sumo (Small Ubiquitin-like MOdifier), to a target protein. This modification is involved in the regulation of various cellular processes such as nuclear-cytosolic transport, transcriptional regulation and progression of cell cycle, among others. Notably, whereas D. melanogaster has only one Sumo protein (Smt3), B. germanica has two, BgSumo1 and BgSumo3. In this thesis, by using RNAi in vivo experiments we have shown that, whereas BgSumo3 is dispensable for the correct development of B. germanica, reduction of BgSumo1 levels resulted in severe defects during the metamorphic transition, including a marked developmental delay due to impaired activation of the ecdysone-triggered signaling cascade. Furthermore, we have shown that all the proteins belonging to the ecdysone-dependent transcriptional cascade of nuclear hormone receptors (BgEcR, BgRXR, BgE75, BgHR3 and BgFTZ-F1) are SUMOylated in vitro. The second part of the thesis is focused on the functional characterization of the E93 gene. First described as a dedicated regulator of cell death, we have demonstrated that this factor controls all the metamorphic transformations in insects. Thus, in the hemimetabolous B. germanica the absence of E93 during the last nymphal instar causes the formation of supernumerary nymphal instars. Moreover, in the holometabolous T. castaneum and D. melanogaster the depletion of E93 impairs adult differentiation during the pupal period and, in the beetle, also causes the formation of a supernumerary pupal stage. Furthermore, E93 controls the essential downregulation of the anti-metamorphic factors Broad and Krüppel homolog-1, two proteins whose presence blocks adult metamorphosis during the pupal stage. In conclusion, our data demonstrate that, despite the evolutionary distance and the differences in the developmental strategies to reach adulthood, E93 is the universal adult specifier in winged insects.
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Lozano, Fernàndez Jesús. "Mecanisme d’acció de l’hormona juvenil en la metamorfosi dels insectes." Doctoral thesis, Universitat de Barcelona, 2014. http://hdl.handle.net/10803/286366.
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La metamorfosi és un procés de canvi morfològic radical que succeeix en un període específic durant el desenvolupament postembrionari de diverses espècies animals, tals com amfibis o insectes. En el cas dels insectes, hi ha dos tipus principals de metamorfosi: de tipus hemimetàbol, on els individus fan una metamorfosi progressiva i les nimfes s’assemblen als adults, com succeeix en les xinxes, paneroles i saltamartins. En la metamorfosi holometàbola, en canvi, es dóna una transformació morfològica radical, de larva a pupa i de pupa a adult, com s’observa en papallones, escarabats i mosques. La metamorfosi holometàbola s’originà a partir d’ancestres hemimetàbols, i aquesta innovació va tenir molt d’èxit si considerem que més del 80% dels insectes actuals són espècies holometàboles. En tots dos tipus de metamorfosi la regulació és propiciada per l’acció de dues hormones, l’esteroide 20-hidroxiecdisona (20E), o hormona de la mud,a i el sesquiterpenoide hormona juvenil (HJ). Mentre que la 20E indueix les mudes, l’HJ reprimeix la metamorfosi. L’objectiu general d’aquesta tesi doctoral és ajudar a comprendre els mecanismes moleculars pels quals l’HJ reprimeix la metamorfosi, utilitzant com a model la panerola Blattella germanica, un insecte amb metamorfosi hemimetàbola poc modificada, i emmarcar aquests resultats en un context evolutiu. Així, hem estudiat el paper del receptor de l’HJ, el factor de transcripció Methoprene-tolerant (Met). Els estudis suprimint l’expressió d’aquest gen mitjançant RNA d’interferència (RNAi) en fases nimfals mostren que Met és necessari en la transducció del senyal hormonal, ja que la seva supressió provoca una metamorfosi precoç. El factor de transcripció Taiman (Tai) es postula com a millor candidat a actuar com a heterodímer de Met en la recepció de l’HJ, encara que cap experiment in vivo ha pogut demostrar aquesta funció degut a que la seva supressió en diversos models d’insectes resultà letal. A B. germanica Taiman s’expressa en quatre isoformes resultants de la combinació de dues insercions/delecions (indels) a la regió carboxi-terminal de la seqüència. La reducció de l'expressió de les isoformes que contenen la inserció-1 de Tai provoca una metamorfosi precoç. La presència d’aquesta inserció en isoformes de Tai d’altres espècies suggereix que el mecanisme de transducció de l’activitat antimetamòrfica de l’HJ mitjançant aquestes isoformes és un fenomen conservat en altres insectes. Un altre factor de transcripció que participa en la senyalització de l'HJ és Broad-Complex (BR-C). A les espècies holometàboles BR-C s’expressa al darrer estadi larvari i la seva expressió transitòria és essencial per una formació de la pupa. Els estudis a B. germanica revelen funcions ancestrals de BR-C relacionades amb divisió cel·lular i creixement de l’ala, alhora que aporten noves pistes que ajuden a entendre l’evolució de la metamorfosi dels insectes. Un altre element important que participa en la transducció del senyal de l’HJ en relació amb la metamorfosi és el factor de transcripció Krüppel-homolog 1 (Kr-h1). Hem mostrat que la reducció de nivells d'expressió de Kr-h1 a fases nimfals a B. germanica indueix una metamorfosi precoç. Aquests resultats, conjuntament amb els resultats previs obtinguts en espècies holometàboles, suggereixen que el paper repressor de Kr-h1 en la metamorfosi és una condició ancestral que s’ha conservat en espècies hemimetàboles i holometàboles. Els microRNAs (miRNAs) són una classe d’RNAs petits no codificants que regulen l’expressió de gens a nivell transcripcional mitjançant la regulació de l’mRNA. Per tal de desvetllar la funció dels miRNAs durant el desenvolupament de B. germanica, es van dur a terme experiments suprimint l’expressió de Dicer-1, enzim que participa en la biosíntesi dels miRNAs, i el resultat va ser una inhibició de la metamorfosi. Els resultats presentats en aquesta tesi suggereixen aquest fenotip és la conseqüència principal d’una davallada de l’expressió d’una sola família de miRNAs, miR-2. El conjunt d’experiments realitzats indiquen que miR-2 regula la davallada de l’expressió del transcrit de Kr- h1 a la darrera fase nimfal de B. germanica, la qual cosa propicia que la metamorfosi es desenvolupi correctament.Metamorphosis is a process were a sudden and conspicuous morphological change occurs at a specific time point during the postembryonic development of several animal groups, like amphibians and insects. Insect metamorphosis proceeds in two modes: hemimetaboly, defined by a gradual change along the life cycle, as occurs in bugs, cockroaches and locusts, and holometaboly, characterized by an abrupt change from larvae to adult mediated by a pupal stage, has observed in butterflies, beetles and flies. Metamorphosis evolved from hemimetaboly to holometaboly and the latter innovation was most successful because more than 80% of present insects are holometabolan species. From an endocrine point of view, both hemimetabolan and holometabolan metamorphosis is regulated by two kinds of hormones: 20-hydroxyecdysone (20E), which induce molts, and juvenile hormone (JH), which inhibits metamorphic changes. Using the cockroach Blattella germanica as a basal hemimetabolous model, the general objective of this thesis is to study the molecular action of JH in repressing insect metamorphosis. One of the main players in hormonal signalling is Methoprene-tolerant (Met), which plays the role of JH receptor. Depletion of Met in young nymphal instars triggers precocious metamorphosis, suggesting that Met transduces the antimetamorphic signal of JH. Recent studies report that Met heterodimerizes with Taiman (Tai) forming the receptor complex of JH in metamorphosis repression. However, there is no data in vivo demonstrating a role of Tai in metamorphosis, because its depletion in a number of insect models resulted in 100% mortality. B. germanica possesses four Tai isoforms resulting from the combination of two indels in the C-terminal region of the sequence. RNAi depletion of insertion-1 isoforms results in a precocious adult development, demonstrating its involvement in metamorphosis. The insertion-1 of Tai is conserved in other insect species, which suggests that the mechanism of signal transduction of the antimetamorphic action of JH I conserved in other species. An important JH-dependent factor is BR-C, whose expression in holometabolan species is inhibited by JH in young larvae and enhanced in mature larvae to specify to pupal stage. The functional study of BR-C in cockroach reveal ancestral functions related to cell division and wing pad growth. Krüppel-homolog 1 (Kr-h1) is a transcription factor whose function as transductor of the antimetamorphic action of JH has been demonstrated in holometabolan species. RNAi experiments depleting Kr-h1 in young nymphal instars of B. germanica results in precocious metamorphosis, suggesting that their role as a JH transductor in metamorphosis is evolutionary conserved in hemimetabolan and holometabolan species. Finally, it has been reported that depletion of dicer-1, the enzyme that catalyzes the final step of miRNA biosynthesis, prevents metamorphosis in B. germanica. This thesis has addressed the question of how miRNAs act in metamorphosis and why their absence impairs it. The whole data of experiments reported here indicate that miR-2 scavenges Kr-h1 transcripts in the last nymphal instar of B. germanica, which contributes to the correct development of metamorphosis.
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Levin, Tracy M. "Evidence for the existence of juvenile hormone in the horseshoe crab." Link to electronic thesis, 2003. http://www.wpi.edu/Pubs/ETD/Available/etd-0528103-140647.
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Kamsoi, Orathai 1987. "Factors regulating metamorphosis in hemimetabolan insects." Doctoral thesis, Universitat Pompeu Fabra, 2020. http://hdl.handle.net/10803/669682.
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The project consists in studying different aspects of the regulation of insect metamorphosis, using the cockroach Blattella germanica and the mayfly Cloeon dipterum, as laboratory models. In B. germanica the idea has been to study the possible role of Myoglianin in regulation of the decrease of juvenile hormone production that occurs at the beginning of the last nymphal instar. Also, to study the possible role of the adult specifier factor E93 in the destruction of the PG after the imaginal molt. In C. dipterum the plan has been to study the mechanisms that regulate metamorphosis, particularly during the formation of the subimago, and to compare these mechanisms with those operating in neopteran insects, which are condensed in the so-called MEKRE93 pathway.El projecte consisteix en estudiar diferents aspectes de la regulació de la metamorfosi dels insectes, utilitzant la panerola Blattella germanica i l’efímera Cloeon dipterum com a models de laboratori. A B. germanica, la idea ha estat estudiar el possible paper de la mioglianina en la regulació de la disminució de la producció d’hormona juvenil que es produeix al començament de l’últim instar nimfal. També ha estat previst estudiar el possible paper del factor especificador de l’adult E93 en la destrucció de la glàndula protorácica després de la muda imaginal. A C. dipterum, el pla ha estat estudiar els mecanismes que regulen la metamorfosi, particularment durant la formació del subimago, i comparar aquests mecanismes amb els que operen en insectes neòpters, condensats en l'anomenada via MEKRE93
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Pólo, André Martins. "Efeito da cafeína no desenvolvimento de Aedes aegypti (Diptera: Culicidae) : o significado biológico das alterações do padrão de síntese de esterases /." São José do Rio Preto, 2014. http://hdl.handle.net/11449/110552.
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Orientador: Hermione Elly Melara de Campos BicudoBanca: Maria Tercília Vilela de Azeredo-Oliveira
Banca: Francisco Chiaravalloti Neto
Resumo: O mosquito Aedes aegypti é vetor dos vírus causadores de doenças humanas entre as quais incluem-se a dengue, a dengue hemorrágica e a febre amarela. A transmissão dessas doenças é feita pelas fêmeas adultas, as quais necessitam de repasto sanguíneo para amadurecimento de seus óvulos. Ao picar indivíduos doentes e depois indivíduos não infectados, as fêmeas transmitem os vírus absorvidos dos primeiros, juntamente com o sangue. Vários estudos mostraram que o tratamento com cafeína (CAF) bloqueia o desenvolvimento e mata A. aegypti na fase larval, impedindo a produção de adultos e, consequentemente, a transmissão das doenças mencionadas. Paralelamente, trabalhos preliminares indicaram que o tratamento do mosquito com CAF altera o padrão de síntese das enzimas esterases. São enzimas que desempenham papel importante em vários processos fisiológicos dos organismos, estando inclusive envolvidas no controle da metamorfose dos insetos. No presente trabalho, as esterases foram analisadas em géis de poliacrilamida corados com α-naftil e β-naftil acetatos e Fast Blue RR. As amostras foram preparadas com larvas L2/L3, L4, pupas e adultos, porém, tendo em vista que a fase L4 foi a que permitiu melhor observação das bandas, o estudo praticamente restringiu-se à mesma. A comparação das amostras dos mosquitos tratados e controle envolveu a observação da presença e da frequência das bandas esterásicas nos géis. Foi também analisado o grau de expressão das bandas com base na intensidade de coloração avaliada pelo programa computacional Global Lab Image. A presente análise mostrou que a CAF altera cinco bandas β-esterásicas (EST-17A a EST-21) e um grupo de bandas α-esterásicas (EST-12 a EST-14). As bandas EST-17A a EST-20 apresentaram redução em ambas as características, enquanto EST-21 e as α-esterases apresentaram aumento. Tendo em vista as variações do grau de expressão das esterases, paralelamente ao ...
Abstract: The mosquito Aedes aegypti is a vector of human disease-causing virus, including dengue, dengue hemorrhagic fever and yellow fever. The transmission of these diseases is made by the adult females, which require blood repast for completing their eggs maturation. When females bite sick individuals and later bite healthy individuals, they transmit the virus absorbed with the blood from the first. Several studies have shown that treatment with caffeine (CAF) blocks development and kills A. aegypti in the larval phase, preventing the production of adults and, consequently, the transmission of the mentioned diseases. In addition, preliminary work indicated that CAF treatment of A. aegypti changes the pattern of synthesis of esterase enzymes. The esterase enzymes play important roles in various physiological processes of the organisms, including among them the control of the metamorphosis of insects. In the present study, the esterases were analyzed in polyacrylamide gels stained with α and ß naphthyl acetates and Fast Blue RR. The samples were prepared with L2, L3 and L4 larval stages, pupae and adults. However, considering that the L4 stage was the one that allowed better observation of the bands, the study was almost restricted to it. The comparison of the treated and control mosquitoes involved observations of the presence and frequency of the esterase bands in the gels. The degree of expression of the bands was also analyzed on the basis of the staining intensity evaluated by the Global Lab Image computer program. The analysis showed that CAF changed five β-esterase bands (EST-17A to EST-21) and a group of α-esterase bands (EST-12 to EST-14). The bands EST-17A to EST-20 showed reduction in both characteristics, while EST-21 and the α-esterases showed increase of them. In view of the changes occurred in the degree of expression of the esterases, parallel to the larval development block we thought in the hypothesis that these esterases ...
Mestre
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Pólo, André Martins [UNESP]. "Efeito da cafeína no desenvolvimento de Aedes aegypti (Diptera: Culicidae): o significado biológico das alterações do padrão de síntese de esterases." Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/110552.
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O mosquito Aedes aegypti é vetor dos vírus causadores de doenças humanas entre as quais incluem-se a dengue, a dengue hemorrágica e a febre amarela. A transmissão dessas doenças é feita pelas fêmeas adultas, as quais necessitam de repasto sanguíneo para amadurecimento de seus óvulos. Ao picar indivíduos doentes e depois indivíduos não infectados, as fêmeas transmitem os vírus absorvidos dos primeiros, juntamente com o sangue. Vários estudos mostraram que o tratamento com cafeína (CAF) bloqueia o desenvolvimento e mata A. aegypti na fase larval, impedindo a produção de adultos e, consequentemente, a transmissão das doenças mencionadas. Paralelamente, trabalhos preliminares indicaram que o tratamento do mosquito com CAF altera o padrão de síntese das enzimas esterases. São enzimas que desempenham papel importante em vários processos fisiológicos dos organismos, estando inclusive envolvidas no controle da metamorfose dos insetos. No presente trabalho, as esterases foram analisadas em géis de poliacrilamida corados com α-naftil e β-naftil acetatos e Fast Blue RR. As amostras foram preparadas com larvas L2/L3, L4, pupas e adultos, porém, tendo em vista que a fase L4 foi a que permitiu melhor observação das bandas, o estudo praticamente restringiu-se à mesma. A comparação das amostras dos mosquitos tratados e controle envolveu a observação da presença e da frequência das bandas esterásicas nos géis. Foi também analisado o grau de expressão das bandas com base na intensidade de coloração avaliada pelo programa computacional Global Lab Image. A presente análise mostrou que a CAF altera cinco bandas β-esterásicas (EST-17A a EST-21) e um grupo de bandas α-esterásicas (EST-12 a EST-14). As bandas EST-17A a EST-20 apresentaram redução em ambas as características, enquanto EST-21 e as α-esterases apresentaram aumento. Tendo em vista as variações do grau de expressão das esterases, paralelamente ao ...
The mosquito Aedes aegypti is a vector of human disease-causing virus, including dengue, dengue hemorrhagic fever and yellow fever. The transmission of these diseases is made by the adult females, which require blood repast for completing their eggs maturation. When females bite sick individuals and later bite healthy individuals, they transmit the virus absorbed with the blood from the first. Several studies have shown that treatment with caffeine (CAF) blocks development and kills A. aegypti in the larval phase, preventing the production of adults and, consequently, the transmission of the mentioned diseases. In addition, preliminary work indicated that CAF treatment of A. aegypti changes the pattern of synthesis of esterase enzymes. The esterase enzymes play important roles in various physiological processes of the organisms, including among them the control of the metamorphosis of insects. In the present study, the esterases were analyzed in polyacrylamide gels stained with α and ß naphthyl acetates and Fast Blue RR. The samples were prepared with L2, L3 and L4 larval stages, pupae and adults. However, considering that the L4 stage was the one that allowed better observation of the bands, the study was almost restricted to it. The comparison of the treated and control mosquitoes involved observations of the presence and frequency of the esterase bands in the gels. The degree of expression of the bands was also analyzed on the basis of the staining intensity evaluated by the Global Lab Image computer program. The analysis showed that CAF changed five β-esterase bands (EST-17A to EST-21) and a group of α-esterase bands (EST-12 to EST-14). The bands EST-17A to EST-20 showed reduction in both characteristics, while EST-21 and the α-esterases showed increase of them. In view of the changes occurred in the degree of expression of the esterases, parallel to the larval development block we thought in the hypothesis that these esterases ...
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Hancock, Robert G. "Effect of larval and adult nutrition on juvenile hormone activity and blood-host seeking by Culex mosquitoes (Diptera: culicidae) and a new method for assaying insect juvenile hormones /." The Ohio State University, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487847761309305.
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Kaur, Jasmit. "A computational study of juvenile hormone analogues." Thesis, University of Reading, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241519.
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Ojani, Reyhaneh. "Molecular mechanisms underlying Juvenile hormone (JH) signaling pathway." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/80342.
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Juvenile hormone (JH) is an important insect hormone that controls diverse biological processes in postembryonic development and adult reproduction. JH exerts its effects through the nuclear receptor Methoprene-tolerant (MET). MET is a transcription factor of the basic helix-loop-helix (bHLH)/Per-Arnt-Sim (PAS) family. In the presence of JH, MET forms a heterodimer with its DNA-binding partner Taiman (TAI). The MET-TAI complex directly binds to the regulatory regions of some JH target genes and regulates their transcription. However many questions remain unanswered regarding the JH-regulated gene expression. The work in this report aims to determine the role of protein kinase C (PKC) in JH signaling in adult mosquitoes and to find the direct target genes of Krüppel homolog 1 (Kr-h1), a zinc finger transcription factor encoded by a JH early response gene.
We discovered that PKC is an essential component of a membrane-initiated JH signaling pathway. PKC was activated by JH in a phospholipase C (PLC)-dependent manner. Inhibition of PKC activity dramatically decreased the JH-induced gene expression. RNAi experiment indicated that several PKC isoforms were involved in the JH action in adult female mosquitoes. We showed that PKC modulated the transactivation activity of MET by enhancing the binding of MET and TAI to the promoters of JH target genes.
Kr-h1 is rapidly upregulated by JH in newly emerged mosquitoes. RNAi-mediated depletion of AaKr-h1 caused a substantial decrease in oviposited eggs, indicating that this protein plays an essential role in mosquito reproduction. We combined chromatin immunoprecipitation (ChIP) with cloning of the generated DNA and have identified chromatin binding sites of AaKr-h1 in Aedes aegypti. After adult emergence, binding of AaKr-h1 to its in vivo targets increased with the JH-induced increase in AaKr-h1. Interestingly, depletion of AaKr-h1 in newly emerged mosquitoes led to considerable upregulation of some AaKr-h1 target genes but downregulation of other target genes. The results suggest that AaKr-h1 acts downstream of AaMET to regulate gene expression in response to JH and that AaKr-h1 can activate or repress the expression of individual target gene.Ph. D.
Books on the topic "Hormonas juveniles"
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Steve, Parker. Hormones: Injury, illness, and health. London: Heinemann Library, 2009.
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Wilson, Michael R. The endocrine system: Hormones, growth, and development. New York, NY: Rosen Pub. Group, Inc., 2009.
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Parker, Steve. Control freak!: Hormones, the brain, and the nervous system. Chicago, Ill: Raintree, 2007.
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Steve, Parker. Control freak: Hormones, the brain and the nervous system. Oxford: Raintree, 2006.
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Steve, Parker. Control freak!: Hormones, the brain, and the nervous system. Chicago, Ill: Raintree, 2007.
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A, Sommers Michael. The NFL: Steroids and human growth hormone. New York: Rosen Central, 2010.
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Bagert, Brod. Hormone jungle: Coming of age in middle school. Gainesville, Fla: Maupin House Pub., 2006.
Find full textBook chapters on the topic "Hormonas juveniles"
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Kleine, Bernhard, and Winfried G. Rossmanith. "Hormones from Mevalonate: Juvenile Hormone and Steroid Hormones." In Hormones and the Endocrine System, 191–236. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-15060-4_6.
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Thakar, Alok. "Adjuvant Chemotherapy and Hormonal Therapy." In Juvenile Angiofibroma, 243–50. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-45343-9_19.
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Granger, Noelle A., and Walter G. Goodman. "Radioimmunoassay: Juvenile Hormones." In Springer Series in Experimental Entomology, 215–51. New York, NY: Springer New York, 1988. http://dx.doi.org/10.1007/978-1-4612-3798-3_7.
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Huang, Zachary Y. "Juvenile Hormone." In Encyclopedia of Social Insects, 1–3. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-319-90306-4_68-1.
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Potter, Daniel A., David W. Held, Felix P. Amerasinghe, David B. Weissman, Amy G. Vandergast, Norihiro Ueshima, David B. Rivers, et al. "Juvenile Hormone." In Encyclopedia of Entomology, 2071–73. Dordrecht: Springer Netherlands, 2008. http://dx.doi.org/10.1007/978-1-4020-6359-6_1667.
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Huang, Zachary Y. "Juvenile Hormone." In Encyclopedia of Social Insects, 535–37. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-28102-1_68.
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Schomburg, Dietmar, and Dörte Stephan. "Juvenile-hormone esterase." In Enzyme Handbook 15, 21–26. Berlin, Heidelberg: Springer Berlin Heidelberg, 1998. http://dx.doi.org/10.1007/978-3-642-58948-5_6.
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Ingelfinger, J. R. "Hormonal Factors in Juvenile Hypertension." In Persistent Renal-Genitourinary Disorders, 137–44. Boston, MA: Springer US, 1987. http://dx.doi.org/10.1007/978-1-4613-2339-6_12.
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Rivera-Pérez, C., M. E. Clifton, F. G. Noriega, and M. Jindra. "Juvenile Hormone Regulation and Action." In Advances in Invertebrate (NEURO)Endocrinology, 1–76. Includes bibliographical references and indexes. | Contents: Volume 2: Arthropoda.: Apple Academic Press, 2020. http://dx.doi.org/10.1201/9781003029861-1.
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Aloni, Roni. "Regulation of Juvenile-Adult Transition and Rejuvenations." In Vascular Differentiation and Plant Hormones, 215–22. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-53202-4_12.
Full textConference papers on the topic "Hormonas juveniles"
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Li, Sheng. "Juvenile hormone signaling in Drosophila." In 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.107253.
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Revenco, Ninel, and Rodica Eremciuc. "AB0963 ROLE OF THYROID HORMONES IN JUVENILE IDIOPATHIC ARTHRITIS." In Annual European Congress of Rheumatology, EULAR 2019, Madrid, 12–15 June 2019. BMJ Publishing Group Ltd and European League Against Rheumatism, 2019. http://dx.doi.org/10.1136/annrheumdis-2019-eular.7974.
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Shin, Sang Woon. "Discovery of plant antagonists of insect juvenile hormone." In 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.93882.
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Nouzova, Marcela. "Targets of neuropeptides regulating juvenile hormone synthesis in mosquitoes." In 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.93907.
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Lindholm, Joliene R. "Elucidating the molecular modes of action of juvenile hormone." In 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.111662.
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Kayukawa, Takumi. "How does juvenile hormone prevent pupal metamorphosis in holometabolous insects?" In 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.105791.
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Noriega, Fernando G. "Metabolic analysis of the juvenile hormone synthesis pathways in mosquitoes." In 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.91917.
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Ojani, Reyhaneh. "Molecular function of Kr-h1 in juvenile hormone-induced gene expression." In 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.105808.
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Togawa, Toru. "Expression ofhairygene is induced by juvenile hormone in tissue-dependent manner." In 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.112319.
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Liu, Pengcheng. "Integration of genomic and nongenomic pathways in juvenile hormone signaling inAedes aegypti." In 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.93862.
Full textReports on the topic "Hormonas juveniles"
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He, Qianyu, and Yuanxi Zhang. Hsp83 Inhibitor Induces Ubiquitin-mediated Proteasomal Degradation of the Juvenile Hormone Receptor Methoprene-tolerant. "Prof. Marin Drinov" Publishing House of Bulgarian Academy of Sciences, April 2018. http://dx.doi.org/10.7546/crabs.2018.03.08.
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Saillant, Eric, Jason Lemus, and James Franks. Culture of Lobotes surinamensis (Tripletail). Mississippi Department of Marine Resources, January 2014. http://dx.doi.org/10.18785/ose.001.
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The Tripletail, Lobotes surinamensis, is a pelagic fish found in tropical and sub-tropical waters of all oceans. Tripletails are often associated with floating debris and make frequent incursions in bays and estuaries where they are targeted by recreational fishermen. In Mississippi waters the species is typically present during the late spring and summer season that also correspond to the period of sexual maturation and spawning (Brown-Peterson and Franks 2001). Tripletail is appreciated as a gamefish but is also prized for its flesh of superior quality. The fast growth rate of juveniles in captivity documented by Franks et al. (2001) and the excellent quality of Tripletail flesh both contribute to the potential of this species for marine aquaculture. In addition, the production of cultured juveniles would be precious to develop a better understanding of the biology, early life history and habitat use of Tripletail larvae and juveniles, a topic largely undocumented to date, through experimental releases and controlled studies. The culture of tripletail thus supports the Tidelands Trust Fund Program through improved conservation of natural resources, potential enhancement of fisheries productivity and potential development of a new economic activity on the Gulf coast producing tripletail via aquaculture. The Objective of this project was to initiate development of methods and techniques needed to spawn captive held tripletail broodfish and raise their offspring to evaluate their growth and development in captivity. In this report we will present the results of studies aiming to develop methods and protocols for captive spawning of tripletail and the first data obtained on the early development of tripletail larvae. A major issue that was encountered with tripletail broodstock development during the project lied in the difficulties associated with identifying the sex of adults caught in the wild and candidates for being incorporated in mating sets for spawning. This issue was addressed during the course of the project by examining the potential of a non-lethal method of hormonal sexing. The results of these preliminary investigations are presented in the third part of this report. All protocols used in the project were determined with the guidance of the Institutional Animal Care and Use Committee (IACUC) of the University of Southern Mississippi (USM IACUC protocol number 10100108).