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Listado como uma das cem piores espécies exóticas invasoras do mundo, o javali asselvajado (Sus scrofa) é o único grande vertebrado cuja caça é autorizada no Brasil. Embora motivada por razões ecológicas e sanitárias, esta autorização, ocorrida em 2013, tem promovido o crescimento do interesse pela caça para fins recreativos no país, após anos de ocaso sociocultural. Diante deste cenário, este artigo discute as relações entre práticas cinegéticas e manejo do javali em duas regiões rurais do Rio Grande do Sul, estado mais meridional do Brasil. Baseado em pesquisa etnográfica e entrevistas, o trabalho discute como agentes do Estado e caçadores concebem e negociam práticas que transitam entre os polos do “controle” e da “caça”, revelando a flexibilidade e relatividade destas categorias. Listed as one of the 100 worst invasive alien species in the world, the wild boar (Sus scrofa) is the only large vertebrate whose hunting is authorized in Brazil. Although motivated by ecological and sanitary reasons, this authorisation, which occurred in 2013, has promoted a growing interest in recreational hunting in the country, after years of sociocultural decline. Given this scenario, this article discusses the relationships between hunting practices and wild boar management in two regions of Rio Grande do Sul’s countryside, Brazil’s southernmost state. Based on ethnographic research and interviews, the paper discusses how state agents and hunters conceive and negotiate practices that move between the poles of “control” and “hunting”, revealing the flexibility and relativity of these categories.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Pigeons are birds that coexist intensely with humans all over the globe, serving as their messengers, as a sign of peace, or a religious icon. In the last decades, however, pigeons seem to have been simply reduced to an urban plague. Before such ambivalence of the pigeons, I set out to ethnography the relations between people and pigeons at the Port of Santos, on the south coast of São Paulo state, where the pigeons are too many and present in an annoying way, due to the large load handling of grains there. From my ethnographic research I show how the pigeons are simultaneously signs and agents; also that biological classifications are not enough to understand the relations between people and pigeons, and how these relations have much to say not only about imposed classifications to pigeons, but also about disputes over urban and portuary spaces, also, institutional and political conflicts. In this way, as of anthropological approach, I think that this research constitutes one more step to our thinking of some sort of different way of living with, on what humans and no humans can live together. Pombos são aves que convivem intensamente com os humanos em muitas partes do globo, servindo como seus mensageiros, como símbolo da paz ou como ícone religioso. Nas últimas décadas, no entanto, pombos parecem ter sido reduzidos, simplesmente, a uma praga urbana. Diante desta ambivalência dos pombos, propus-me a etnografar as relações entre pessoas e pombos no Porto de Santos, no litoral sul do estado de São Paulo, onde os pombos se fazem presentes em demasia, de forma incômoda, devido à grande movimentação de grãos no local. A partir de minha pesquisa etnográfica evidencio como os pombos são, simultaneamente, signos e agentes; como as classificações biológicas não bastam para compreender as relações entre pessoas e pombos, e como estas relações têm muito a dizer não apenas das classificações que são (im)postas aos pombos, mas ainda das disputas pelo espaço urbano e portuário e dos conflitos institucionais e políticos que ali se desenrolam. Deste modo, e a partir da antropologia, penso que esta pesquisa constitui um passo a mais para nossa imaginação de modos diferentes de conviver, em que humanos e não humanos possam viver juntos.

The endoplasmic reticulum and casein-containing vesicles contribute to milk fat globule membrane formation. 10. Journées de Biologie Cellulaire du Grand Campus

The mammary gland is an atypical mammalian exocrine organ which develops according to the reproductive status and whose main function is to produce large quantities of milk to feed newborns during lactation. Milk is a complex fluid containing proteins (mostly caseins), sugars (mainly lactose), lipids and minerals, as well as bioactive molecules such as immunoglobulins (IgA), growth factors and hormones, which are secreted by distinct pathways. All the developmental steps, as well as milk secretion, are finely tuned by the systemic hormonal status, local paracrine regulations and a constant dialogue of mammary epithelial secretory cells (MESCs) with both the extracellular matrix (ECM) and the adjacent cells. The aim of our project is to decipher the molecular mechanisms involved in milk product secretion and their regulations. While lactose and milk proteins are released by exocytosis involving SNARE proteins (soluble N-ethylmaleimide-sensitive-factor attachment protein receptor) [1, 2], the fat fraction of milk (milk fat globules, MFGs) is secreted by budding, being enwrapped by the apical plasma membrane (APM) [3]. As the latter process required a huge surface of membrane, we first asked whether, in addition to the APM, membranes provided by the SVs upon exocytosis and possibly by intracellular compartments may contribute to the formation of the MFGs membrane (MFGM). Moreover, the secretion of both caseins and MFGs appears to be coordinated at time of suckling. Thus, another question was whether common molecular actors may exist to allow the coupling of caseins and MFGs secretion and if so, whether common mechanisms could regulate this process.Références1 - Chat et al., 2011, Eur J Cell Biol. 90(5):401-13.2 - Truchet et al., 2014, J Mammary Gland Biol Neoplasia. 19(1):119-30.3 – Mather & Keenan, 1998, J Mammary Gland Biol Neoplasia. 3(3):227-32.

Introduction. Casein micelles and milk fat globules (MFGs) are major milk components both of which being secreted at the apical side of the mammary epithelial cell (MEC) during lactation. Caseins are released by exocytosis while MFGs are excreted by budding, being enwrapped by the apical plasma membrane. Nevertheless, the molecular mechanisms involved in milk products secretion are still not fully deciphered. Due to their size (4 µm average diameter in bovine), the expulsion of MFGs obviously requires a very important amount of membrane. This could be partly provided by the exocytosis of secretory vesicles containing caseins but other sources of membranes are likely. Moreover, the secretion of these various milk products seems to be coordinated at the time of suckling, suggesting the existence of regulatory mechanisms common to the processes of protein exocytosis and lipid budding. In this context, we investigated the role of SNARE proteins (soluble N-ethylmaleimide-sensitive factor activating protein receptor) which are the core fusion machinery of cell membranes in the secretion of milk products. [br/]Results. We previously showed that SNARE proteins are expressed in the mouse mammary gland at different physiological stages, and especially during lactation, and that some of these proteins are actually associated with caseins containing secretory vesicles and/or with intracellular lipid droplets (LDs), as well as with MFGs [1]. Our results showed that SNAP-23 is associated with both LDs and MFGs, and that this protein is often present at the interface between the casein containing vesicles and the LDs at the apical pole of MECs. SNAP-23 has already been demonstrated at the membrane of bovine MFGs [2] and could play a role in intracellular growth of LDs [3]. We have also observed other SNARE proteins such as VAMP-8 and Sec22B at the surface of mouse MFGs. Interestingly, VAMP-8 is associated with both casein containing vesicles and intracellular LDs in the MECs of lactating mouse. The differential analysis of proteins associated with intracellular LDs and MFGs by mass spectrometry provides important informations concerning the compartments providing membrane for the secretion of MFGs. [br/]Conclusion. Taken together, our results suggest that the membrane allowing the secretion of MFGs comes from several compartments, including at least caseins containing secretory vesicles and the endoplasmic reticulum. Moreover, it is likely that the protein SNAP-23 is a common actor to both secretory vesicles exocytosis and budding of MFGs, thus constituting a potential regulatory point for the coordinated secretion of milk products. [br/]Perspectives. The functional role of SNAP-23 in the secretion of milk products will be determined using tools such as botulinum toxin E (BoNT/E) and siRNAs directed against SNAP-23.[br/]References.[1] Chat et al., 2011, Eur J Cell Biol 90(5):401-13.[2] Reinhardt & Lippolis, 2008, J Dairy Sci 91(6):2307-18.[3] Boström et al., 2007, Nat Cell Biol 9(11):1286-93.

The mammary gland is a complex tissue which function is to ensure the offspring’s feeding by producing and secreting milk during lactation. Casein micelles and fat globules (MFGs) are essential constituents of milk and are both secreted at the apical side of mammary epithelial cells (MECs) during lactation. MFGs are excreted by budding, being enwrapped by the apical plasma membrane, while caseins contained in transport vesicles are released by exocytosis. The lactogenic hormone prolactin (PRL) not only induces the synthesis of caseins but also an increase of arachidonic acid (AA) in MECs, which may accelerate the apical transport and possibly the exocytosis of caseins (secretagogue effect of PRL). Nevertheless, the molecular mechanisms governing casein exocytosis are, to date, not fully deciphered. By forming stable ternary complexes, SNARE (Soluble NSF Attachment Receptor) proteins constitute the core fusion machinery for cellular membrane trafficking and exocytosis events in many cell types. In addition, SNAREs have recently been described as target for AA, thus promoting exocytosis in neuroendocrine cells. We therefore attempted to identify the SNARE proteins involved in caseins secretion in the mouse mammary gland during lactation. An exciting possibility is that the SNAREs involved in caseins’ exocytosis can be the target of AA released in response to PRL.

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