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Based on the ethnographic description of a recent event — a road accident in July 2022 — the paper analyzes the mechanization process of indigenous worlds and, in particular, of the practical consequences of the diffusion of motorcycles among the Chacobo (Panoan) of the Bolivian Amazon. The event is analyzed as a social drama that allows to shed light on some of the social, ethnic, economic, technological and environmental transformations that are currently reshaping the indigenous reality in the South American lowlands.

Abstract Background DNA methylation is an important epigenetic modification which has numerous roles in modulating genome function. Its levels are spatially correlated across the genome, typically high in repressed regions but low in transcription factor (TF) binding sites and active regulatory regions. However, the mechanisms establishing genome-wide and TF binding site methylation patterns are still unclear. Results Here we use a comparative approach to investigate the association of DNA methylation to TF binding evolution in mammals. Specifically, we experimentally profile DNA methylation and combine this with published occupancy profiles of five distinct TFs (CTCF, CEBPA, HNF4A, ONECUT1, FOXA1) in the liver of five mammalian species (human, macaque, mouse, rat, dog). TF binding sites are lowly methylated, but they often also have intermediate methylation levels. Furthermore, biding sites are influenced by the methylation status of CpGs in their wider binding regions even when CpGs are absent from the core binding motif. Employing a classification and clustering approach, we extract distinct and species-conserved patterns of DNA methylation levels at TF binding regions. CEBPA, HNF4A, ONECUT1, and FOXA1 share the same methylation patterns, while CTCF's differ. These patterns characterize alternative functions and chromatin landscapes of TF-bound regions. Leveraging our phylogenetic framework, we find DNA methylation gain upon evolutionary loss of TF occupancy, indicating coordinated evolution. Furthermore, each methylation pattern has its own evolutionary trajectory reflecting its genomic contexts. Conclusions Our epigenomic analyses indicate a role for DNA methylation in TF binding changes across species including that specific DNA methylation profiles characterize TF binding and are associated with their regulatory activity, chromatin contexts, and evolutionary trajectories.

Se analiza una etnografía reciente sobre la reparación y el mantenimiento de motocicletas en Rumania desde la Segunda Guerra Mundial a la actualidad. A partir del detalle de las premisas analíticas y conceptuales del estudio antropológico de la cultura motociclística, de los propios recortes del objeto, de las estrategias metodológicas para documentarlo y de algunas de las particularidades más significativas del escenario histórico de la modernidad postsoviética y “la sociedad de la post-reparación”, se argumenta que es posible repensar el fenómeno aparentemente técnico de la mecánica motociclística como un auténtico hecho social total que modula un set de variables geopolíticas, económicas, técnicas, identitarias, simbólicas, estéticas, etarias y de género. Finalmente, se proponen algunas líneas posibles de exploración comparativa con otros estudios actuales sobre etnomecánica, movilidades y en particular la difusión contemporánea de motocicletas en áreas culturales muy distintas entre sí, que echan luz sobre las configuraciones relacionales posibles entre tecnología, medioambiente y sociedad.

Abstract Background To investigate the mechanisms driving regulatory evolution across tissues, we experimentally mapped promoters, enhancers, and gene expression in the liver, brain, muscle, and testis from ten diverse mammals. Results The regulatory landscape around genes included both tissue-shared and tissue-specific regulatory regions, where tissue-specific promoters and enhancers evolved most rapidly. Genomic regions switching between promoters and enhancers were more common across species, and less common across tissues within a single species. Long Interspersed Nuclear Elements (LINEs) played recurrent evolutionary roles: LINE L1s were associated with tissue-specific regulatory regions, whereas more ancient LINE L2s were associated with tissue-shared regulatory regions and with those switching between promoter and enhancer signatures across species. Conclusions Our analyses of the tissue-specificity and evolutionary stability among promoters and enhancers reveal how specific LINE families have helped shape the dynamic mammalian regulome.

Reseña de Pierre Déléage, La folie arctique. Bruselas: Zones sensibles, 2017, 102 pp. ISBN 978-293- 0601-26-7

Cardiovascular disease collectively accounts for a quarter of deaths worldwide. Genome-wide association studies across a range of cardiovascular traits and pathologies have highlighted the prevalence of common non-coding genetic variants within candidate loci. Here, we review genetic, epigenomic and molecular approaches to investigate the contribution of non-coding regulatory elements in cardiovascular biology. We then discuss recent insights on the emerging role of non-coding variation in predisposition to cardiovascular disease, with a focus on novel mechanistic examples from functional genomics studies. Lastly, we consider the clinical significance of these findings at present, and some of the current challenges facing the field.

Para la mayoría de los americanistas Jehan A. Vellard (1901-1996) es un desconocido. Para muchos es apenas una referencia bibliográfica más, y para otros tan solo el médico que acompañó al Mato Grosso a Claude Lévi-Strauss. Definitivamente Vellard no es un contemporáneo: su obra resulta anticuada, poco glamorosa y carece de potencia heurística, mientras que su autor se presenta como un ancestro incómodo, antipático, que nadie reivindica. Sin embargo, contentarse con este diagnóstico sería demasiado fácil. El descarte disciplinar de la figura de Vellard deja escapar una personalidad polifacética, testigo de tiempos críticos para el Chaco, los Andes o la Amazonía, y al mismo tiempo una obra que combina la etnografía, la antropología física, la lingüística, la arqueología y la biología. Se trata, entonces, de revisar desapasionadamente algunas de las expediciones científicas que Vellard realiza para el Museo del Trocadero en la década de 1930, en particular los viajes al Paraguay (1931-1932) en vísperas de la guerra del Chaco y al Mato Grosso (1938) en la famosa expedición con Lévi-Strauss, y de repasar las circunstancias específicas en las cuales se conformó una parte de las colecciones del museo. Al mismo tiempo, el análisis permite echar luz sobre las ambigüedades del legado personal y científico de Vellard

The early ethnological works of Alfred Métraux are analysed bearing in mind his first fieldwork trip to the Chiriguano, in 1929. The paper discusses personal, academic and professional features of Métraux’s ethnological experience, the nature of the 1929 trip and his concrete relationships with the Chiriguano groups and individuals. Next, we analyse his ideas on material culture as a priviledged means of understanding the synthes is of Andean, Chaco and Amazonian cultural influences. Finally, the dilemmas and limitations of his analytical approach regarding Créole cultural influence and social and cultural change are discussed.

Se describe primero la «prehistoria» católica del contacto entre los grupos panos de la actual Amazonía boliviana y los misioneros jesuitas, franciscanos y del clero secular. Luego se analiza la continuidad del proceso de evangelización de los chacobos por diversas denominaciones evangélicas, reflejada en tres experiencias misioneras desde 1955 hasta la actualidad. Por último, se proponen algunas reflexiones sobre el problema antropológico de la conversión religiosa.

El artículo describe la visita del viajero alemán Heinz Rox-Schulz (1921-2004) a los chacobos de la Amazonía boliviana en 1959, y la colección fotográfica que resultó de ese viaje. Discute luego la experiencia de devolución de las imágenes a los chacobos en 2013, reflexionando brevemente sobre las percepciones chacobo de la representación gráfica y su influencia en la dinámica contemporánea de definición social de la historia, la cultura y la identidad étnica.

Late Colonial documents about Bolivian Amazonia show us the ubiquity of «Pacaguara» Indians. However, during the second half of the 20th Century, several discourses by missionaries, scientists, politicians and even journalists regret the imminent extinction of the «the last of the Pacaguaras», hardly a dozen individuals settled with the Chacobo of Alto Ivon since the 1960s. Contrary to this fatalism, the National Census of 2012 reveals a surprising number of 161 Pacaguara. The paradoxical reasons of this demographic boom are discussed in terms of the indigenous and external manipulation of the representations of ethnic identity.

Whether codon usage fine-tunes mRNA translation in mammals remains controversial, with recent papers suggesting that production of proteins in specific Gene Ontological (GO) pathways can be regulated by actively modifying the codon and anticodon pools in different cellular conditions. In this work, we compared the sequence content of genes in specific GO categories with the exonic genome background. Although a substantial fraction of variability in codon usage could be explained by random sampling, almost half of GO sets showed more variability in codon usage than expected by chance. Nevertheless, by quantifying translational efficiency in healthy and cancerous tissues in human and mouse, we demonstrated that a given tRNA pool can equally well translate many different sets of mRNAs, irrespective of their cell-type specificity. This disconnect between variations in codon usage and the stability of translational efficiency is best explained by differences in GC content between gene sets. GC variation across the mammalian genome is most likely a result of the interplay between genome repair and gene duplication mechanisms, rather than selective pressures caused by codon-driven translational rates. Consequently, codon usage differences in mammalian transcriptomes are most easily explained by well-understood mutational biases acting on the underlying genome.

Se analizan diversas informaciones sobre los llamados “panos meridionales” desde fines del siglo XVIII a mediados del siglo XX. Se discute, especialmente, el juego variable de relaciones entre los etnónimos que aparecen en las fuentes(“pacaguaras”, “chacobos”, “caripunas”), su extensión en el espacio, y la formación de grupos sociales. Para ello se propone que estos etnónimos designan categorías genéricas que reflejan diversas experiencias de contacto entre los panos meridionales y otros grupos indígenas, los misioneros jesuitas, franciscanos y seculares, los barones caucheros, los militares y exploradores coloniales y luego republicanos.

The relevance of some classical ideas of the anthropological study of religions for the understanding of Chané religion is examined. In order to examine two basic premises —the degree of possibility of intercultural translation and the relative character of contexts of meaning— several aspects are discussed: the relationships between symbolism and diverse features of social structure; the problem of symbolic ambivalence; the coexistence of pragmatic and symbolic dimensions of action; the idea of the sacred as interdiction; the preeminence of ritual; the systematic character of religious beliefs; the exegetical, conceptual and metaphysical implications of the missionary use of indigenous notions to translate the Christian idea of the «soul»; and the selective integration of foreign cultural influences.

The Chiriguano Ethnology of Alfred Métraux. The paper analyzes the influence of Erland Nordenskiöld and Marcel Mauss on the early academic, intellectual and professional career of Alfred Métraux. In a broader perspective it focuses on the theoretical and methodological influence of French sociology and the Scandinavian school of Americanist ethnology on Métraux’s first researches on historical and living Tupi-Guarani groups, particularly the Tupinamba and Chiriguano. We pursue our analysis across diverse aspects of Métraux’s work, including: his treatment of religion and prophetism among the Tupinamba; his participation in the pioneer project that created the Ethnology Institute in Tucuman; the manifestation of ideology, inherited prejudice and esthetic values in his gathering of material culture collections; the singularities of Métraux’s fieldwork and its impact on his relationship with the Chiriguano; his thesis that Chiriguano pottery reflected particular mixtures of Andean, Chaco and Amazonian influences; and, finally, the significant link he found between mythic symbolism and the feminine universe.

O ponto de partida deste artigo é a tese desenvolvida em 1991 por Isabelle Combès e Thierry Saignes sobre o nascimento da etnia e da identidade chiriguano, mestiças "em essência". A relação que os Chiriguano e os Chané mantêm com a mestiçagem parece, no entanto, paradoxal. Embora sejam considerados exemplos paradigmáticos de mestiçagem ameríndia, algumas visões contemporâneas sentenciam a dissolução da etnia devido precisamente à mestiçagem com os brancos. Ao mesmo tempo, os próprios Chiriguano rejeitam atualmente qualquer idéia de mistura, proclamando-se apenas "guarani". A partir de um duplo estudo de caso no Isoso boliviano e no noroeste argentino, relativiza-se o postulado da completa absorção dos Chané pelo conjunto Chiriguano; depois são analisados os diferentes tipos de mestiçagem existentes e sua relação com um esquema assimétrico que cria uma verdadeira escala de valores entre diferentes etnias. Finalmente, sugere-se que a ambivalência ideológica que envolve a mestiçagem se deve ao fato de que ela é precisamente uma construção híbrida, produto da fusão entre as ideologias chané e guarani.The starting point of this article is the thesis developed in 1991 by Isabelle Combès and Thierry Saignes on the birth of Chiriguano ethnicity and identity, both mixed ‘in essence.’ The Chiriguano and the Chané appear to maintain a somewhat paradoxical relationship with miscegenation, however. Although considered paradigmatic examples of Amerindian miscegenation, some contemporary views anticipate the dissolution of the ethnic group precisely because of its mixture with whites. At the same time, the Chiriguano themselves reject any idea of mixture, proclaiming themselves to be simply ‘Guarani.’ Based on a double case study of the Bolivian Isoso and the Argentinean Northwest, the article casts doubt on the idea of the complete absorption of the Chané by the Chiriguano complex; it then analyzes the different types of miscegenation in existence and their relation to an asymmetrical schema that creates a scale of values between different ethnic groups. Finally, the authors suggest that the ideological ambivalence surrounding miscegenation is precisely due to the fact that it is a hybrid construct, the product of the fusion between Chané and Guarani ideologies.

Chané aristocracies. « Houses » in the Argentinian and Bolivian Chaco. While the classic views of chané leadership posits powerless leaders and democratic assemblies, ethnographical and ethnohistorical data suggest to the contrary quite powerful and hereditary dynasties. After presenting two case-studies, the Chané of northwestern Argentina and the Bolivian Izoceños, the application of the concept of « House » – as developed by Lévi-Strauss – is proposed in order to explain the Chané political system. It is argued that the traditional account of the leadership is mainly a « Guaranized » one, which can not fully explain the Chané facts. The final section deals with the future of the Chané Houses in the more « democratic » times impulsed by contemporary indigenous movements.

The transcriptional response driven by Hypoxia-inducible factor (HIF) is central to the adaptation to oxygen restriction. Despite recent characterization of genome-wide HIF DNA binding locations and hypoxia-regulated transcripts in different cell types, the molecular bases of HIF target selection remain unresolved. Herein, we combined multi-level experimental data and computational predictions to identify sequence motifs that may contribute to HIF target selectivity. We obtained a core set of bona fide HIF binding regions by integrating multiple HIF1 DNA binding and hypoxia expression profiling datasets. This core set exhibits evolutionarily conserved binding regions and is enriched in functional responses to hypoxia. Computational prediction of enriched transcription factor binding sites identified sequence motifs corresponding to several stress-responsive transcription factors, such as activator protein 1 (AP1), cAMP response element-binding (CREB), or CCAAT-enhancer binding protein (CEBP). Experimental validations on HIF-regulated promoters suggest a functional role of the identified motifs in modulating HIF-mediated transcription. Accordingly, transcriptional targets of these factors are over-represented in a sorted list of hypoxia-regulated genes. Altogether, our results implicate cooperativity among stress-responsive transcription factors in fine-tuning the HIF transcriptional response.

When oxygen becomes limiting, cells reduce mitochondrial respiration and increase ATP production through anaerobic fermentation of glucose. The Hypoxia Inducible Factors (HIFs) play a key role in this metabolic shift by regulating the transcription of key enzymes of glucose metabolism. Here we show that oxygen regulates the expression of the muscle glycogen synthase (GYS1). Hypoxic GYS1 induction requires HIF activity and a Hypoxia Response Element within its promoter. GYS1 gene induction correlated with a significant increase in glycogen synthase activity and glycogen accumulation in cells exposed to hypoxia. Significantly, knockdown of either HIF1alpha or GYS1 attenuated hypoxia-induced glycogen accumulation, while GYS1 overexpression was sufficient to mimic this effect. Altogether, these results indicate that GYS1 regulation by HIF plays a central role in the hypoxic accumulation of glycogen. Importantly, we found that hypoxia also upregulates the expression of UTP:glucose-1-phosphate urydylyltransferase (UGP2) and 1,4-alpha glucan branching enzyme (GBE1), two enzymes involved in the biosynthesis of glycogen. Therefore, hypoxia regulates almost all the enzymes involved in glycogen metabolism in a coordinated fashion, leading to its accumulation. Finally, we demonstrated that abrogation of glycogen synthesis, by knock-down of GYS1 expression, impairs hypoxic preconditioning, suggesting a physiological role for the glycogen accumulated during chronic hypoxia. In summary, our results uncover a novel effect of hypoxia on glucose metabolism, further supporting the central importance of metabolic reprogramming in the cellular adaptation to hypoxia.

El objetivo de este libro de Enric Porqueres es reseñar el desarrollo de una de las herramientas más características y actualmente menos empleada de la antropología: el método genealógico. No se trata, o no se trata solamente, de describir el apogeo y caída de esta herramienta como si se tratara de un tema más de una historia caduca del pensamiento antropológico, sino también, por sobre todo, de replantear sus diversas posibilidades de articulación con otras problemáticas contemporáneas en la investigación social.

Llamados hasta hace algunos años “matacos”, los wichí del Gran Chaco forman parte del grupo lingüístico mataco-mataguayo junto con los maká, los nivaclé y los chorote. Se trata de unas 40.000 personas que conforman una suerte de complejo o cadena étnica cuyos eslabones mantienen afinidades lingüísticas pero a la vez considerables diferencias en cuanto a la lengua y a las costumbres, y se distinguen entre sí mediante un sistema de identificación cuyo criterio rector es la posición relativa respecto de la línea cardinal de los ríos que atraviesan la región – así, cada uno de los grupos llama “arribeños” (phomlheléy) a la parcialidad que le sigue inmediatamente río arriba, y “abajeños” (cho’mlheléy) a la que le sigue río abajo.

De origen arawak, el grupo étnico que la literatura amerindia llamó chané se estableció antes de la Conquista en El Chaco occidental, sobre las laderas orientales de los Andes. Allí trabó complejas relaciones interétnicas con otros grupos étnicos de habla guaraní, indígenas chaqueños y luego, en la medida en que se consolidó el proceso de colonización, también con diversos actores criollos: hacendados, patrones de ingenios, militares, misioneros. A través de documentación etnográfica y etnohistórica, se sugiere que el funcionamiento abierto, flexible, maleable e integrador del chamanismo chané lleva la marca de estas múltiples interacciones históricas, lo cual, por otra parte, lo transforma en un lenguaje simbólico ideal para problematizar las situaciones de contacto intercultural.