Diss. (sammanfattning). Alnarp : Sveriges lantbruksuniversitet, 2005. / Härtill 7 uppsatser.

Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [84]-100).

The cell division of Saccharomyces cerevisiae is controlled by the action of pheromones at the G1 phase of the cell cycle. A general method was developed for the isolation of constitutive mutants in the pheromone response pathway. Recessive alleles of the SCG1 gene (encoding the α subunit of a G protein) were isolated as well as a dominant mutation in the STE4 gene (encoding the β subunit of a G protein). Analysis of double mutants suggested that the STE4 gene product functions after the SCG1 product but before the STE5 gene product. Double mutants carrying either scg1 or STE4Hp1 constitutive alleles together with the temperature-sensitive unresponsive mutation, ste5-3ts, showed arrest and recovery when shifted from 34° C to 22° C. Recovery from the constitutive signal was independent of the receptor. The STE4Hp1 sst2 ste5ts triple mutant was not able to recover from arrest, suggesting that an SST2-dependent mechanism is involved in recovery of the STE4Hp1 mutant from constitutive arrest. In contrast, the scg1-7 sst2 ste5ts triple mutant recovered only partially suggesting that even though SST2 gene product is probably involved in recovery of the scg1-7 mutant, this mutant can recover by an SST2-independent mechanism. This implies existence of another, SST2-independent postreceptor recovery mechanism. The scg1-null mutant do not recover from constitutive arrest (J. Hirschman, personal communication). Both recovery mechanisms probably operate at the G protein step. Isolation of a constitutive allele of STE5 allowed the definition of its site of action as being after the STE4-controlled step. In addition, constitutive activation of the pheromone pathway by STE5Hp1 mutation was found to be partially dependent on the STE4 and STE18 gene products, the β and γ subunits of a G protein. A comprehensive genetic model is presented to explain the mechanisms of signal transduction and recovery.

La seiche commune Sepia officinalis est un Mollusque Céphalopode présent sur les côtes Normandes. En Baie de Seine, elle représente la troisième espèce visée par les flottilles hauturière et côtière, ce qui en fait une ressource économique importante pour la région. Dans un contexte de protection de la ressource, l’étude et la compréhension des mécanismes liés à la reproduction représentent un objectif majeur. Cette étude est donc focalisée sur les mécanismes régulateurs de la ponte, et en particulier sur les facteurs impliqués dans l’émission des ovocytes. Des recherches antérieures effectuées au laboratoire ont mis en évidence un contrôle multifactoriel du processus de ponte, avec trois niveaux de régulation. (i) Les neuropeptides sont impliqués dans la perception des paramètres environnementaux, (ii) les facteurs ovariens assurent la régulation paracrine du tractus génital, et (iii) les phéromones sexuelles, tout en interférant avec la ponte, sont suspectées de jouer un rôle important dans le comportement des géniteurs associé à la reproduction. Cette thèse met en lumière le rôle de 2 familles de neuropeptides identifiées récemment : les CCAPs et les FLGamides (ou So-orcokinines B). Ces deux familles participent au transport de l’ovocyte et à la sécrétion capsulaire en agissant sur l’activité contractile du complexe oviducte/glande de l’oviducte et des glandes nidamentaires principales. Ces neuropeptides sont par ailleurs suspectés de jouer un rôle dans la biosynthèse des protéines vitellines et des protéines capsulaires. Parallèlement, des phéromones sexuelles sont exprimées par la glande de l’oviducte et sécrétées avec les protéines capsulaires. Des travaux antérieurs ont permis de caractériser des produits d’expression issus de clivages de type prohormone convertase. Dans cette nouvelle étude, un second mode de clivage a été mis en évidence avec l’identification de produits de clivage de masse moléculaire supérieure à 20 kDa. L’un de ces produits, la phéromone beta, a été produit en système recombinant mais son activité biologique sur l’appareil génital mâle et sur l’oviducte n’a pas été démontrée. Quant aux tests comportementaux, ils n’ont pu être exploités du fait d’un nombre d’animaux testés trop restreint. Enfin, une approche transcriptomique comparative et différentielle réalisée à partir de l’organe olfactif mâle et du pavillon de l’oviducte a permis d’identifier un récepteur candidat à la liaison avec les phéromones sexuelles / The common cuttlefish (Sepia officinalis) is a Cephalopod mollusk found on the Normandy coasts. In the Bay of Seine, it is the third species targeted by offshore and coastal fleets, so it is an important economic resource for the whole region. In a context of resource protection, the study and understanding of its reproductive mechanisms is a major objective. This study is therefore focused on the regulatory mechanisms of egg-laying, and in particular on the factors involved in the release of oocytes. Previous research in the laboratory demonstrated multifactorial control of the egg-laying process, with three levels of regulation: (i) neuropeptides involved in the perception of environmental cues, (ii) ovarian factors providing paracrine regulation of the genital tract, and (iii) sexual pheromones, which are implied in egg-laying and are suspected to play a determining role in the reproductive behavior. This thesis highlights the role of two families of recently identified neuropeptides called CCAPs and FLGamides (or So-orcokinins B). These two families participate in oocyte transport and in egg capsule secretion by acting on the contractile activity of the oviduct/oviduct gland complex and of the main nidamental glands. These neuropeptides are also suspected to play a role in the biosynthesis of yolk and capsular proteins. At the same time, sex pheromones are expressed by the oviduct gland and secreted along with capsular proteins. Previous work made it possible to characterize expression products resulting from cleavages of the prohormone convertase type. In this new study, a second mode of cleavage is highlighted, evidenced by the identification of cleavage products with MWs greater than 20 kDa. One of these products, beta pheromone, was produced in a recombinant system but its biological activity on the male reproductive system and on the oviduct was not demonstrated. As for behavioral tests, they were not exploited because the number of animals tested was too small. Finally, a comparative and differential transcriptomic approach of the male olfactory organ and the oviduct pavilion evidenced a candidate receptor expected to bind to sex pheromones

A maioria dos Lepidoptera utiliza feromônio sexual para atração do parceiro para o acasalamento. A técnica da interrupção do acasalamento ou confusão sexual de machos é usada para interferir na comunicação entre os parceiros sexuais. Isto é obtido com a liberação de altas doses de feromônio sintético, para saturar o ambiente em que se deseja fazer o controle e, desta forma, diminuir a habilidade dos machos em localizar as fêmeas. O bicho-mineiro do café Leucoptera coffeella é considerado atualmente a principal praga desta cultura no Brasil. O controle químico tem sido o mais utilizado para impedir o ataque deste inseto, causando sérios problemas para o homem e para o meio ambiente. Para amenizar estes problemas, atualmente têm-se desenvolvido novas técnicas de manejo das pragas que atacam esta cultura. O presente trabalho testou, em campo, a viabilidade da técnica de confusão sexual de machos para a redução da população do bicho mineiro do café e com isso a diminuição do prejuízo que este inseto causa à lavoura. Foram instaladas três unidades experimentais de 20 ha. em uma lavoura de café. A eficiência desta técnica foi testada por meio da comparação de machos capturados em armadilhas iscadas com feromônio, entre a área tratada com o feromônio sexual para confundimento e outras duas áreas não tratadas com feromônio. Outra forma de avaliar a eficiência foi por meio da intensidade de injúrias que o inseto causou as folhas. Avaliando os resultados obtidos, pode-se implicar que o emprego do feromônio sexual sintético de L. coffeella não foi efetivo para reduzir os acasalamentos da espécie-praga e para diminuir o dano causado as plantas. Nesse contexto o insucesso pode ser atribuído a uma combinação de vários fatores, merecendo destaque à composição química, dose do feromônio e a formulação empregada, o momento de aplicação na lavoura, densidade populacional e a estratégia de acasalamento da praga, além do tamanho da área tratada e dos fatores climáticos._________________________________________________________________________________________ ABSTRACT: Most Lepidoptera use sex pheromones for the attraction of a mate. A technique for controlling lepidopteron pests, denominated mating disruption, aims at obstructing the communication between sexual partners. This is obtained with the release of synthetic pheromone in order to saturate the atmosphere, thereby decreasing the ability of mates to locate each other. The coffee leaf miner Leucoptera coffeella is the main pest of the coffee in Brazil. Chemical control has been used frequently to control the attack of L. coffeella, but this causes serious problems to man and environment. To avoid such problems, new techniques are being developed currently to control the attack of this pest. The present work is a field test of the viability of mating disruption to reduce coffee leaf miner populations and consequently, decrease its damage to the crop. Three experimental units of 20 ha. were installed in a coffee plantation. The intensity of mating disruption was tested through the comparison of synthetic-baited pheromone traps in areas where the sex pheromone was applied and two untreated areas. Another form to measure intensity of mating disruption was through the level of damage that the insect caused to the leaves. The results showed that the employment of the synthetic sex pheromone of L. coffeella did not reduce the mating of the insects and did not decrease the damage of plants. The failure of the mating disruption technique may be attributed to a combination of several factors, such as composition and/or dose of the pheromone and its formulation, the moment of application in the crop, the population density and the mating strategy of the pest, the size of the treated area as well as climatic factors.

A agressão maternal tem como função preservar a vida da prole. O desenvolvimento desse comportamento depende vastamente do reconhecimento do adversário como uma ameaça potencial e esse reconhecimento envolve a detecção de pistas feromonais. O núcleo pré-mamilar ventral (PMv) é um dos principais alvos do núcleo medial da amígdala, que representa o setor amigdalar crítico para o processamento de pistas feromonais. Desta forma, postulamos que possivelmente o PMv seja sensível às pistas feromonais do macho intruso, servindo como uma possível interface para os sistemas neurais envolvidos na agressão maternal. Neste sentido, inicialmente avaliamos o padrão de ativação do PMv, bem como alguns de seus alvos de projeção, durante o comportamento maternal e durante a agressão maternal. Notamos que tanto o PMv como a maioria de seus alvos principais (tais como, o núcleo posterior da amígdala, a parte posterodorsal do núcleo medial da amígdala, a área hipotalâmica lateral tuberal e a parte ventrolateral do núcleo ventromedial) apresentam um aumento significativo na expressão da proteína Fos durante a agressão maternal. Em seguida, avaliamos o papel do PMv na organização neural do comportamento de agressão maternal, em ratas lactantes portadoras de lesões citotóxicas com NMDA do PMv. Os resultados obtidos neste estudo demonstram que as fêmeas lactantes com lesão no PMv não apresentam qualquer alteração nos parâmetros comportamentais relacionados ao comportamento maternal, mas apresentam uma significante diminuição no comportamento agressivo maternal. Observamos ainda, que a lesão citotóxica do PMv resultou numa drástica diminuição da expressão da proteína Fos em alguns sítios de projeção do PMv que se apresentavam mobilizados durante a agressão maternal (tais como a parte ventrolateral do hipotálamo ventromedial, a área hipotalâmica lateral tuberal e o núcleo pré-óptico medial), sugerindo a participação destes sítios neurais como críticos na expressão do comportamento de agressão maternal. / Maternal aggression is critical to preserve the litters from male intruders, and the pheromonal cues from the males are important to drive such responses. The ventral premamillary nucleus (PMv) is one of the main targets of the medial amygdalar nucleus, and is critically involved in processing pheromonal information. In this regard, in the present study, we investigated whether the PMv would work as a putative interface between the pheromonal processing of the male intruder and the neural sites potentially involved in the expression of maternal aggression. First, we analyzed the pattern of Fos expression in dams expressing aggressive maternal behavior, and found a significant increase in Fos levels in the PMv, as well as, in most of its main targets, such as the posterior amygdalar nucleus, the posterodorsal part of the medial amygdalar nucleus, the tuberal nucleus of the lateral hypothalamic area, and the ventrolateral part of the ventromedial nucleus. Next, we examined how NMDA lesions bilaterally placed in the PMv would interfere in maternal aggression, and found that dams bearing those lesions presented a significant reduction in the expression of aggressive behavior, but showed no alterations on the maternal behavior responses. Moreover, we were able to see that PMv lesions resulted in significant drop in Fos expression in selected PMv targets, namely the tuberal nucleus of the lateral hypothalamic area and the ventrolateral part of the ventromedial nucleus, likely to be critically involved in the expression of the maternal aggression. Overall, the present results support the idea that the PMv is seemingly a key site in the network controlling maternal aggression; on one hand, the nucleus is likely to processes pheromonal cues from the intruder male, and, on the other, it conveys this information to sites critically related to the expression of maternal aggression.

O objetivo do presente trabalho foi investigar a relação do núcleo pré-mamilar ventral (PMV): 1) na regulação do sistema reprodutivo em fêmeas, 2) como mediador dos efeitos da leptina e 3) na resposta à estimulação feromonal. Para tanto, induzimos lesão bilateral do PMV em ratas. Foi observado que a lesão do PMV promove: alteração no ciclo estral e da histologia ovariana; redução dos níveis de estradiol e LH; e supressão de vias neurais que controlam o eixo reprodutivo. Além disso, a lesão do PMV impediu que a administração central de leptina induzisse secreção de LH durante o jejum. Em outros experimentos, realizados em ratos machos, verificou-se que neurônios que sintetizam óxido nítrico no PMV e no núcleo medial da amígdala são ativados em resposta ao odor de conspecíficos, em especial o de fêmeas. Assim, foi demonstrado que o PMV exerce papel relevante na regulação do sistema reprodutivo e media a ação estimulatória da leptina na secreção do LH. Além disso, o PMV faz parte do circuito neural relacionado com a resposta aos feromônios. / The objective of this study was to assess the role played by the ventral premammillary nucleus (PMV): 1) in the regulation of the female reproductive system, 2) as a mediator of the effects of leptin and 3) in response to pheromonal stimulation. For this purpose, we produced bilateral PMV lesions in female rats. We observed that PMV lesion: disrupted the estrous cycle and altered the number of ovarian antral follicles; reduced the estradiol and LH levels; and suppressed neural pathways that control the reproductive axis. We found that lesions of the PMV blocked leptin stimulation of LH secretion during fasting. In another experiment using male rats, we showed that nitric oxide synthesizing neurons in the PMV and medial nucleus of amygdala are activated by conspecific odors, especially female odors. Thus, we showed that PMV plays an important role in the control of females reproductive system and mediates the stimulatory effects of leptin on LH secretion. Also, PMV is part of the neural circuitry related to pheromonal responses.

Orientador: Anita Jocelyne Marsaioli / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-21T20:30:57Z (GMT). No. of bitstreams: 1 Pianaro_Adriana_D.pdf: 8531703 bytes, checksum: 86c8399c69a5d82f0e333fed92903d03 (MD5) Previous issue date: 2012 / Resumo: Este trabalho teve como objetivo a comunicação química em insetos sociais e em particular de abelhas sem ferrão e formigas lava-pés brasileiras. Portanto, estes dois tópicos foram abordados em dois capítulos distintos e revelaram que: (1) As rainhas virgens de M. quadrifasciata com abdomes inflados liberam uma mistura de nerol/geraniol na razão 1:2, respectivamente, pelas glândulas tergais. Estes monoterpenos indicam o nível de maturidade destas rainhas e podem estar envolvidos na seleção de uma nova rainha. Rainhas fisogástricas de S. aff. depilis atraem machos e a partir da descoberta deste fenômeno iniciou¿se a procura dos compostos responsáveis pela atração sexual. As análises dos extratos epicuticulares, extratos abdominais, glândulas de Dufour e glândulas tergais das rainhas fisogástricas e virgens de S. aff. depilis revelaram ésteres no extrato das rainhas fisogástricas. Os testes de campo com os extratos, as frações dos compostos isolados de rainhas fisogástricas de S. aff. depilis e padrões sintéticos revelaram que os extratos epicuticulares das rainhas fisogástricas atraem e estimulam a cópula dos machos quando adsorvidos sobre feltro preto. As frações e os padrões não produziram nenhuma resposta. A presença de 2-alcanóis nos extratos cefálicos de rainhas de M. quadrifasciata e S. aff. depilis e machos de N. testaceicornis estimulou a realização de testes de campo com 2-alcanóis, os quais demonstraram que o (S)-(+)-2-heptanol e a mistura (S)-(+)-2-heptanol/ (S)-(+)-2-nonanol (1:1) atraem operárias de P. droryana, N. testaceicornis e F. silvestrii, sugerindo ser um feromônio de recrutamento de operárias e envolvidos na formação de leques de machos. (2) A análise dos alcalóides dos venenos de operárias e rainhas de S. saevissima revelou diferenças na composição química intra e inter-nidal de duas regiões diferentes do Brasil (São Paulo e Rio de Janeiro). Uma metodologia para acesso rápido das configurações relativas e absolutas dos alcalóides piperidínicos do veneno das formigas lava-pés foi elaborada empregando CG-EM e CG-DIC com coluna capilar quiral Chrompack CP-chirasil-Dex CB e derivados trifluoroacetamidas e acetamidas dos alcalóides piperidínicos sintéticos e naturais, onde se verificou pela primeira vez a presença dos quatro estereoisômeros da 2-metil-6-undecilpiperidina em venenos de formigas lava-pés. / Abstract: The aim of this thesis is the chemical communication of social insects and in particular of Brazilian stingless bees and fire ants. Therefore, the results obtained in these two topics are presented in two chapters as follows: (1) Virgin queens of M. quadrifasciata (stingless bee) with inflated abdomens release a mixture of nerol/ geraniol in 1:2 ratio, respectively, by tergal glands. These monoterpenes are related to the development of these queens and may be involved in the new queen selection. S. aff. depilis physogastric queens attract drones and this observation oriented the research to sexual pheromones. The analysis of the epicuticular, abdominal, Dufour¿s gland, and tergal gland extracts of S.aff. depilis from physogastric and virgin queens revealed the outstanding presence of esters in the epicuticular extracts of physogastric queens. Field tests with extracts, isolated compound fractions of S. aff. depilis physogastric queens and synthetic standards revealed that physogastric queen epicuticular extracts attract and stimulate mating of drones when adsorbed on black felt. The fractions and standards produced no response. The presence of 2-alkanols in cephalic extracts of M. quadrifasciata and S. aff. depilis queens and N. testaceicornis drones stimulated field tests with 2-alkanols, which showed that the (S)-(+)-2-heptanol and the mixture of (S)-(+)-2-heptanol/ (S)-(+)-2-nonanol (1:1) attract workers of P. droryana, N. testaceicornis and F. silvestrii. This biological response is consistent with worker recruit pheromones, involved in the formation of drone swarms. (2) Analysis of the venom alkaloids of S. saevissima workers and queens revealed differences in the intra and internidal chemical composition of fire ants from two different regions in Brazil (Sao Paulo and Rio de Janeiro). A methodology to rapidly access the relative and absolute configurations of the piperidinic alkaloids from the fire ant venom was developed using GC-MS and GC-FID with a chiral capillary column (Chrompack CP-chirasil-Dex CB) and trifluoroacetamides and acetamides of synthetic and natural piperidinic alkaloids. This methodology was applied to the analysis of 2-methyl-6-undecylpiperidine of S. saevissima gynes and worker venoms from Ubatuba-SP and Pedro do Rio-RJ revealing for the first time the presence of four stereoisomers of 2-methyl-6-undecylpiperidine in the fire ant venoms. / Doutorado / Quimica Organica / Doutora em Ciências

Recent research has shown that sexual activity may be influenced by variables suggested by evolutionary theory, such as pheromonal cues. A recent study in our laboratory indicated that female pheromones influence men’s drinking and approach behavior based on hidden pathways of behavioral influence caused by chemosensory signals. The current study sought to examine whether a link exists between male pheromones and women’s drinking and approach behavior, through the use of a possible male sex pheromone called androstenone, and sought to examine this link within the context of a women’s ovulation cycle. One hundred and three female participants were primed with either androstenone or a control scent and then completed measures assessing their beer consumption, approach behavior, and ovulatory phase. Results of the study indicated that females who were exposed to the androstenone prime drank significantly more than those exposed to the control prime, though results indicated no differences between groups in terms of approach behavior. No interaction effects existed between group condition and ovulatory phase on beer consumption or approach behavior; however, a limited amount of participants were ovulating when they completed the study, as indicated by a biological assay. The results from the current study implicate a specific pathway to alcohol use through biological signals within a sexual context. The findings from this study expand the existing literature on olfactory and pheromone signaling of sexual behavior in humans and shed light on newly uncovered biological pathways of influence on human behaviors.

That odors play a significant role in subhuman intraspecies communication is a generally accepted fact explained in part by the production and reception of species specific pheromones. Recently the effects of human produced odors on human communication have received research attention, particularly in the communication of such biological phenomena as menstruation onset and gender assignment. Again pheromones have been posited as the explanatory mechanism. Whether a pheromone-like odor cued process exists in the communication of human emotions is unknown, though a number of anecdotal accounts of odor-emotion interactions suggest that such may be the case. It was the purpose of the present study to investigate a possible odor-emotion interaction by determining whether humans could differentially detect other humans' odor collected under varying emotional conditions.