Genetic Evidence for a Mitochondriate Ancestry in the ‘Amitochondriate’ Flagellate Trimastix pyriformis

Most modern eukaryotes diverged from a common ancestor that contained the α-proteobacterial endosymbiont that gave rise to mitochondria. The ‘amitochondriate’ anaerobic protist parasites that have been studied to date, such as Giardia and Trichomonas harbor mitochondrion-related organelles, such as mitosomes or hydrogenosomes. Yet there is one remaining group of mitochondrion-lacking flagellates known as the Preaxostyla that could represent a primitive ‘pre-mitochondrial’ lineage of eukaryotes. To test this hypothesis, we conducted an expressed sequence tag (EST) survey on the preaxostylid flagellate Trimastix pyriformis, a poorly-studied free-living anaerobe. Among the ESTs we detected 19 proteins that, in other eukaryotes, typically function in mitochondria, hydrogenosomes or mitosomes, 12 of which are found exclusively within these organelles. Interestingly, one of the proteins, aconitase, functions in the tricarboxylic acid cycle typical of aerobic mitochondria, whereas others, such as pyruvate:ferredoxin oxidoreductase and [FeFe] hydrogenase, are characteristic of anaerobic hydrogenosomes. Since Trimastix retains genetic evidence of a mitochondriate ancestry, we can now say definitively that all known living eukaryote lineages descend from a common ancestor that had mitochondria

Against Global Archaeological Ethics: Critical Views from South America

Archaeology as a discipline has been formed largely as a nation-state biopolitical device generating narratives and actions of control, management, classification, and ordering of persons and objects, pasts and presents, their stories, relationships and spaces from a Anglo-Saxon modern mode of knowledge production. In that sense, hegemonic archeology bears its colonial imprint and exhibits the principles that characterize modern Western science of universality, objectivity and rationalism. Thus, archeology has developed and expanded in close partnership with capitalism generating a true industry and mercantilization of the past. Simultaneously, it has been tried to globalize the vision of Western archeology and install a monoculture of knowledge to disqualify others worldview reducing and contracting the present and eliminating those conceptions that do not fit with the scientific canons and principles.Fil: Curtoni, Rafael Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Investigaciones Arqueológicas y Paleontológicas del Cuaternario Pampeano. Universidad Nacional del Centro de la Provincia de Buenos Aires. Investigaciones Arqueológicas y Paleontológicas del Cuaternario Pampeano; Argentin

Patrons against clients: Electoral uncertainty and bureaucratic tenure in politicized states

Why would incumbents undertake institutional reforms that constrain their discretion over state resources? Many studies point to electoral competition in response. They argue that incumbents who risk exit from office undertake reform to insure themselves against potentially hostile successors. This paper challenges this line of reasoning, arguing that it confounds two potential implications of electoral competition – potential and certain electoral losses – which yield contrary reform incentives. Certain exits from office may well incentivize reforms as insurance. Where elections are contested, however, incumbents face incentives to resist reforms that constrain discretion over state resources that provide incumbents with electoral advantage. This argument is developed and assessed with an institutional reform the literature has so far neglected: job stability protections (tenure) in politicized bureaucracies. A case analysis of the Dominican Republic and suggestive cross-country data confirm theoretical predictions: electoral uncertainty dis-incentivizes tenure reform. Electoral competition may thus be a double-edged sword for institutional reform