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Orientador: Valmir Fadel / Banca: Claudia Munte / Banca: João Ruggiero Neto / Resumo: Os venenos de vespas socias são ricos em peptídeos biologicamente ativos que causam alguns males ao ser humano como: dores prolongadas, edema, eritema, reações alérgicas e sistêmicas. Possuem em sua composição vários tipos de aminas biogênicas, peptídeos e proteínas. Dentre eles, o que chama mais atenção na atividade farmacológica do veneno são os peptídeos policatiônicos. São diversas as atividades desses peptídeos como: neurotoxicidade, hemólise, liberação de histamina de mastócitos e antibatericida. Neste trabalho, foram estudados peptídeos catiônicos da família Polybine, sintetizados pelo Departamento de Biologia, Unesp, Rio Claro-SP. Os peptídeos Polybine I e II foram sintetizados na forma acetilada e não-acetilada para o estudo detalhado da sua estrutura. Com este objetivo, utilizamos as técnicas de Dicroísmo Circular (CD), para uma análise da estrutura secundária da amostra e espectroscopia de Ressonância Magnética Nuclear (RMN) para o estudo da estrutura tridimensional do peptídeo em solução. / Abstract: Social wasp venoms are rich of biologically active peptides that may cause some malady to human such as prolonged pains, edema, erythema, allergies and systemic reactions. They have, in its composition, many kinds of biogenic amines, series of polycationics peptides and proteins. Among them, the most interesting thing in pharmacological activity are the polycationics peptides. These peptides show several activities like neurotoxicity, hemolytic activity, histamine releasing activity and antimicrobial activity. In this project, cationic peptides of the Polybine family synthesized by the Department of Biology, CEIS/IBRC, UNESP, Rio Claro, SP were studied. The cationic peptides Polybine I and II were synthesized in acetylad and non-acetylad forms to the detailed study of the structure. This way, CD spectroscopy were performed to analyze secondary structure of the sample and, to analyze treedimension structure, NMR spectroscopy were used. / Mestre

Etude des Treg dans la physiopathologie du syndrome de Wiskott-Aldrich et étude de la reconstitution des Treg dans les greffes de cellules souches hématopoïétiques après un conditionnement nonmyéloablateur.

For most of the animals, if not all, finding their way to a particular place is crucial for survival. To address this challenge of way-finding, different animals have evolved with different homing strategies. Social hymenopterans like honey bees, ants and wasps are of special interest – foragers of these insects show excellent homing capabilities while having simple neural resources. In this study field, honey bees and ants (desert ants, in particular) are among the most studied animals. Compared to these insects, our understanding on the homing mechanisms of social wasp is rather poor. For my thesis, I have studied homing behaviour of the tropical social wasp Ropalidia marginata, a predator in their foraging habit. To begin with, first I had to know their typical foraging range, which I found to be within about 500 m from their nest. Forager wasps possess a surprisingly well-developed familiarity with their foraging landscape, apparently more intricate than honey bees and desert ants. They acquire this spatial familiarity through flying around the landscape before starting foraging for food. Compared to honey bees and desert ants, this learning period in wasps appears to be much longer – this can be attributed to the much higher density of the tropical landscape in which they have evolved. I have also found that, if needed, they can fly to a distance of about 1.5 km for foraging and can return to their nest even if passively displaced to familiar and unfamiliar places. To return from unfamiliar places, they probably use some sort of searching mechanisms – a skill that they improve with their age. Such searching behaviour is prevalent throughout other hymenopteran insects. I conclude that capability and mechanisms of spatial orientation, navigation and homing in animals are much influenced by their evolutionary origin and the environment in which they have evolved.

Reproduction is the avenue for gaining direct fitness. But in certain species some individuals do not reproduce, instead gain indirect fitness by helping relatives to reproduce; the prime examples for this come from the worker caste of social insects like ants, bees and wasps. For explaining such a perplexing paradox, also known as altruism, W.D. Hamilton proposed that individuals can gain fitness in two ways: directly, by reproducing (direct fitness), and indirectly, by helping relatives to reproduce (indirect fitness). Indirect fitness has since been the main focus for explaining the evolution of workers while usually overlooking the fact that workers can also gain direct fitness. One of the avenues for gaining direct fitness by workers is nest foundation and we have studied this phenomenon in a primitively eusocial wasp Ropalidia marginata. We found that workers routinely leave their natal nests to initiate new nests either alone or with a few other wasps. Before leaving their natal nests, such workers prepare in several ways for nest foundation, like enhancing their nutrient reserves and forming outside nest aggregations to engage in dominance interactions. Next, we investigated the emergence of cooperation and division of labour in newly founded nests and how these affect the productivities of the new nests. We found that while two wasps are sufficient for the emergence of cooperation and reproductive division of labour (DOL), it takes three wasps for non-reproductive DOL to emerge; cooperation and reproductive DOL are not sufficient for increasing colony productivity which comes about only with the addition of non-reproductive DOL. Finally, we found that it is ageing and nutrition, and not work done towards gaining indirect fitness that affect workers’ potential of gaining future direct fitness by independent reproduction via nest foundation, in other words, current indirect fitness is not incompatible with future direct fitness.

Thesis (MSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Cuticular hydrocarbon (CHC) profiles of insects play roles in behavioural interactions within and between species, encompassing species-, colony- and mate-recognition. CHCs are largely genetically determined and are thus unique to each species, making them useful in chemotaxonomy. However, species exhibit intra-species variation in their CHC profile which can be the result of both intra-species genetic variation as well as environmental influences such as habitat effects, colony effects, diet, host switching, as well as adsorption of CHCs from other insects. Studies have found that the CHC profiles of a specific insect species will often exhibit variations between regions as well as the species of host the insect is associated with. Therefore, an ideal system to investigate the effects of genetic population structure and environment on the CHC profiles of insects is within the fig – fig wasp mutualism. Fig species occur in a wide variety of habitats and host a diverse complement of fig wasp species. We were therefore offered the opportunity to investigate a wide range of potential influences on fig wasp CHC profiles ranging from environmental to genetic effects. Firstly, through GC-MS we found that the CHC profiles of the fig wasps investigated are both species-specific and species-group-specific, with the species Elisabethiella glumosae, Elisabethiella stuckenbergi and Ceratosolen capensis, and two Otitesella species-groups (the Uluzi and Sesqui species-groups) separating out significantly. Consensus phylogenies (based on COI, Cytb and EF-1α) showed that within the galling fig wasp genus Otitesella there were multiple genetic lineages within a species-group which corresponds to species-level genetic variation, and that each genetic lineage was confined to a single host fig species. The CHC profiles reflected the genetic relationships between the two species-groups, and the CHC profiles within a species group could be differentiated by genetic lineage/host species. This indicated that although genetic lineage was mostly responsible for the observed variation in CHC profiles, factors associated with different host species also had an effect. Strong regional variation overriding both the influence of genetic lineage and factors associated with host species were observed in the CHC profiles of the fig wasps within a species-group. This regional variation in CHC profiles was also observed within two pollinating fig wasp species, Elisabethiella stuckenbergi and Ceratosolen capensis, which was not supported by population genetic data (COI and Cytb). In fact, very little genetic population structure was found within the pollinating species, even though the pollinators were collected across South Africa. The lack of genetic structure in pollinating fig wasps can be the result of high gene flow caused by the large dispersal capability of pollinating fig wasps. Our results indicated that fig wasp CHC profiles have the potential to be used in chemotaxonomy and are possibly used as species and mate-recognition cues by the fig wasps. Furthermore, we found both a regional and associated host species effect on the CHC profile. We suggest that the observed regional effect in this study could be attributed to habitat differences and differences in fig wasp community between regions. Moreover, the effect host species had on the CHC profiles may be as a result of dietary differences between galls in different host species. A possible consequence of the observed regional/host speciesassociated effect on fig wasp CHC profiles is that it could lead to pre-mating isolation within fig wasp species, which could ultimately result in speciation. In addition, our results indicated that the interpretation of the variation in the fig wasp CHC profile was dependent on the scale of the analysis: on a broad, inter-species-level scale, fig wasp CHC profiles were species-specific; on a finer intra-species scale, variation in CHC profiles occurred between fig wasps collected from different regions; and on a within-region scale, variation in CHC profiles within species-groups occurred between genetic lineages/host species. Future studies should look at the application of CHCs in chemotaxonomic studies on the fig wasp phylogeny, as well as the effect of fig wasp community composition on fig wasp CHCs. / AFRIKAANSE OPSOMMING: Kutikulêre koolwaterstof (KK) profiele van insekte speel rolle in die gedragsinteraksies binne sowel as tussen spesies, en behels die herkenning van spesieof kolonielidmaatskap asook potensiële maats. Kutikulêre koolwaterstowwe word meestal deur gene bepaal en is dus uniek vir elke spesie, wat dit handig maak vir chemotaksonomie. Spesies vertoon egter soms intraspesie variasie in hul KK profiele wat die gevolg kan wees van beide intraspesie genetiese variasie sowel as omgewingsinvloede soos habitat effekte, kolonie effekte, dieet, tussen-gasheer skuiwings, asook die adsorpsie van ander insekte se kutikulêre koolwaterstowwe. Studies het gevind dat die kutikulêre koolwaterstof profiele van ʼn spesifieke insek spesie op ʼn gereelde basis verskille vertoon tussen streke asook tussen die verskillende gasheer spesies waarmee die insek geassosieer is. Om hierdie redes is die vy – vy-wesp mutualisme ʼn ideale sisteem om die uitwerking van genetiese populasie struktuur en omgewing op die KK profiele van insekte te ondersoek. Vy spesies kom in ʼn wye verskeidenheid van habitatte voor en ondersteun ʼn diverse groep vy-wesp spesies. Dit het ons die geleentheid gebied om ʼn wye reeks moontlike invloede van vy-wesp KK profiele te ondersoek, van omgewings- tot genetiese invloede. Eerstens, deur die gebruik van GC-MS het ons gevind dat die KK profiele van die vy-wespe wat ondersoek was beide spesie-spesifiek en spesie-groep-spesifiek is, met die spesies Elisabethiella glumosae, Elisabethiella stuckenbergi en Ceratosolen capensis, asook twee Otitesella spesie-groepe (die Uluzi en Sesqui spesie-groepe) wat betekenisvol onderskei kon word. Konsensus filogenieë (gegrond op COI, Cytb en EF1-1α) het getoon dat daar in die gal-induserende vy-wesp genus Otitesella veelvuldige genetiese lyne binne die spesie-groepe voorgekom het ooreenstemmend met tussen-spesie genetiese variasie, en dat elke genetiese lyn beperk was tot ʼn enkele gasheer vy spesie. Die KK profiele het die genetiese verhoudings tussen die twee spesie-groepe weerspieël, en die KK profiele binne ʼn spesie-groep kon onderskei word op grond van hul genetiese lyn/gasheer spesie. Hierdie het getoon dat, alhoewel genetiese lyn meestal verantwoordelik was vir die waargeneemde variasie in KK profiele, faktore wat met verskille in gasheer spesies gepaard gaan ook ʼn effek gehad het. Sterk streeks-verbonde variasie wat beide die invloed van genetiese lyn, én faktore wat met verskille in gasheer spesie gepaard gaan, oortref het, was waargeneem in die KK profiele van die vy-wespe binne ʼn spesie-groep. Hierdie streeks-verbonde variasie in KK profiele was ook waargeneem in twee bestuiwende vy-wespe, Elisabethiella stuckenbergi en Ceratosolen capensis, ʼn resultaat wat nie ondersteun was deur die genetiese bevolkingsdata nie (COI en Cytb). In werklikheid was baie min genetiese bevolkings-struktuur opgespoor binne die bestuiwer spesies, selfs as was die bestuiwer spesies regoor Suid-Afrika ingesamel. Die tekort aan genetiese struktuur in die vy-wesp bestuiwers kan die gevolg wees van hoë geenvloei wat veroorsaak word deur die hoë verspreidingskapasiteit van bestuiwende vy-wespe. Die resultate toon aan dat vy-wesp KK profiele die potensiaal besit om in chemotaksonomie gebruik te word, en word moontlik deur vy-wespe gebruik as kenmerke vir die herkenning van spesie en potensiële maats. Verder was daar gevind dat daar beide ʼn streekseffek en ʼn effek geassosieer met gasheer spesie op KK profiele was. Ons stel voor dat die waargeneemde streekseffek in hierdie studie toegeskryf kan word aan verskille tussen habitatte asook streeksverbonde verskille tussen vy-wesp gemeenskappe. Boonop kan die effek wat gasheer spesie op die KK profiele gehad het ʼn gevolg wees van dieetverskille tussen die galle in verskillende gasheer spesies. ʼn Moontlike gevolg van die waargeneemde streeks/gasheer-spesie-geassosieerde effek op vy-wesp KK profiele is dat dit moontlik kon lei tot voor-paring-isolasie binne vy-wesp spesies, wat uiteindelik spesiasie kon veroorsaak het. Daarbenewens wys ons resultate dat die interpretasie van die variasie in die vy-wesp KK profiel was afhanklik van die skaal van die analise: op ʼn breë interspesie vlak was die vy-wesp KK profiele spesiespesifiek; op ʼn fyner intra-spesie vlak het variasie in KK profiele voorgekom tussen vy-wespe wat in verskillende streke ingesamel was; en op streeksvlak het variasie in die KK profiele binne spesie-groepe voorgekom tussen genetiese lyne/gasheer spesies. Toekomstige studies behoort te kyk na die toepassing van kutikulêre koolwaterstowwe in chemotaksonomiese studies van die vy-wesp filogenie, asook die effek wat vy-wesp gemeenskap samestelling het op vy-wesp kutikulêre koolwaterstowwe.

Societies where workers sacrifice their own reproduction and cooperatively nurture the offspring of a reproductive queen caste have originated repeatedly across the Tree of Life. The attainment of such reproductive division of labor enabled the evolution of remarkable diversity in development, behavior, and social organization in the Hymenoptera (ants, bees, and wasps). Wasps of the family Vespidae exhibit a gamut of social levels, ranging from solitary to highly social behavior. The highly social yellowjackets and hornets (Vespinae) have well developed differences in form and function between queens and workers, large colony sizes, and intricate nest architecture. Moreover, certain socially parasitic species in the Vespinae have secondarily lost the worker caste and rely entirely on the workers of a host species to ensure the survival of parasitic offspring. Understanding the evolution of behavioral traits in the Vespinae over long periods of time would be greatly enhanced by a robust hypothesis of historical relationships. In this study, I analyze targeted genes and transcriptomes to address three goals. First, infer phylogenetic relationships within yellowjackets (Vespula and Dolichovespula) and hornets (Vespa and Provespa). Second, test the hypothesis that social parasites are more closely related to their hosts than to any other species (Emery's rule). Third, test the protein evolution hypothesis, which states that accelerated evolution of protein coding genes and positive selection operated in the transition to highly eusocial behavior. The findings of this study challenge the predominant understanding of evolutionary relationships in the Vespinae. I show that yellowjacket genera are not sister lineages, instead recovering Dolichovespula as more closely related to the hornets, and placing Vespula as sister to all other vespine genera. This implies that traits such as large colony size and high paternity are mostly restricted to a particular evolutionary trajectory (Vespula) from an early split in the Vespinae. I demonstrate that obligate and facultative social parasites do not share immediate common ancestry with their hosts, indicating that socially parasitic behavior likely evolved independently of host species. Moreover, obligate social parasites share a unique evolutionary history, suggesting that their parasitic behavior might have a genetic component. Lastly, I analyze transcriptomic data to infer a phylogeny of vespid wasps and use this phylogeny to discover lineage-specific signatures of positive selection. I identify more than two hundred genes showing signatures of positive selection on the branch leading to the highly eusocial yellowjackets and hornets. These positively selected genes involve functions related mainly to carbohydrate metabolism and mitochondrial activity, in agreement with insights from studies of bees and ants. Parallels of functional categories for genes under positive selection suggests that at the molecular level the evolution of highly eusocial behavior across the Hymenoptera might have followed similar and narrow paths.

Cynipid gall wasps have fascinating biology that has piqued the interest of naturalists throughout history. They induce morphologically complex, sometimes spectacular, gall structures on plants in which the larval stages develop. Gall wasps have therefore evolved an intimate association with their hosts - both metabolically, and in terms of their population histories. Gall wasps must both interact physiologically with their hosts to induce galls, and track their host plants through space and time. My thesis centres on two uses of genomic data in understanding the biology of the oak apple gall wasp Biorhiza pallida. I provide a comprehensive investigation into patterns of oak and gall wasp gene expression associated with gall induction, and a population genomic reconstruction of the population history of this species across the Western Palaearctic. While advances in sequencing technology and reduced costs have made these aims possible, analysis of the massive resulting datasets generated creates new challenges. Firstly, in reconstructing the population history of B. pallida, I describe the use of shotgun sequencing and an informatic pipeline to generate alignments of several thousand loci for three B. pallida individuals sampled from putative glacial refugia across the Western Palaearctic in Iberia, the Balkans and Iran. This dataset was analysed using a new maximum likelihood method capable of estimating population splitting and admixture among refugia across very large numbers of loci. The results showed an ancient divide between Iberia and the other two refugia, followed by very recent admixture between easternmost and westernmost regions. This suggests that gall wasps have migrated westwards along the North African coast as well as through mainland Europe. Second, I compare the gene expression profiles of gall wasp and oak tissues sampled from each of three stages of gall development, leading to new insights into potential mechanisms of gall wasp-oak interaction. A highly expressed gall wasp protein was identified that is hypothesised to stimulate somatic embryogenesis-like development of the gall through interaction with oak tissue glycoproteins. Highly expressed oak genes include those coding for nodulin-like proteins similar to those involved in legume nodule formation. Finally, analysis of the gall wasp genome has revealed potential, but as yet unconfirmed, horizontal gene transfer events into gall wasp genomes. Genes discovered in three gall wasp genomes and expressed in three transcriptomes encode plant cell wall degrading enzymes. They are not of hymenopteran origin, and are most homologous to genes of plant pathogenic bacteria. These genes could be involved in several aspects of gall wasp biology, including feeding and developmental manipulation of host plant tissue.

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