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The origin of prophetism in the Ancient Near East  [cached]
Gerda de Villiers
HTS Theological Studies/Teologiese Studies , 2010, DOI: 10.4102/hts.v66i1.795
Abstract: This article aimed to give an overview of the early attestations to prophecy in the Ancient Near East (ANE) in order to stimulate reflection on what could be understood by ‘prophetism’. The most extant sources for prophetic oracles in the ANE were uncovered at the royal archives of Mari and Nineveh, therefore some evidence of these sites has been indicated. Consequently the distinction between ‘inductive’ and ‘non-inductive’ forms of divination was also discussed. Furthermore it was questioned whether the critique against ANE-prophecy as ‘Heilsprophetie’ (‘salvation’) as opposed to the ‘Unheilsprophetie’ (‘doom’) of Old Testament can still be upheld. Finally some notes of caution were raised with regard to the careless appropriation of the term ‘prophetism’ in the 21st century. How to cite this article: De Villiers, G., 2010, ‘The origin of prophetism in the Ancient Near East’, HTS Teologiese Studies/Theological Studies 66(1), Art. #795, 6 pages. DOI: 10.4102/hts. v66i1.795.
Ancient Pbx-Hox signatures define hundreds of vertebrate developmental enhancers
Hugo J Parker, Paul Piccinelli, Tatjana Sauka-Spengler, Marianne Bronner, Greg Elgar
BMC Genomics , 2011, DOI: 10.1186/1471-2164-12-637
Abstract: Here, we identify ancient functional signatures within vertebrate conserved non-coding elements (CNEs) through a combination of phylogenetic footprinting and functional assay, using genomic sequence from the sea lamprey as a reference. We uncover a striking enrichment within vertebrate CNEs for conserved binding-site motifs of the Pbx-Hox hetero-dimer. We further show that these predict reporter gene expression in a segment specific manner in the hindbrain and pharyngeal arches during zebrafish development.These findings evoke an evolutionary scenario in which many CNEs evolved early in the vertebrate lineage to co-ordinate Hox-dependent gene-regulatory interactions that pattern the vertebrate head. In a broader context, our evolutionary analyses reveal that CNEs are composed of tightly linked transcription-factor binding-sites (TFBSs), which can be systematically identified through phylogenetic footprinting approaches. By placing a large number of ancient vertebrate CNEs into a developmental context, our findings promise to have a significant impact on efforts toward de-coding gene-regulatory elements that underlie vertebrate development, and will facilitate building general models of regulatory element evolution.Cis-regulatory elements play an essential role in the precise co-ordination of vertebrate development as illustrated by the increasing number of examples where mutations in such sequences lead to developmental malformations [1-3]. One of the major challenges in modern biology is the deciphering of the regulatory language, syntax and grammar, encoded in the genome, that directs spatio-temporally restricted gene expression. To achieve this requires the identification and functional characterisation of cis-regulatory elements, followed by the deconvolution of the TFBSs therein.Cis-regulatory elements can be predicted by sequence conservation analysis, as tight clusters of functional TFBSs can be under strong evolutionary constraint [4-7]. Alternatively, targe
Comparative Assessment to Danger of Rock Bursts Origin in Different Conditions of Mining in OKR  [PDF]
Bukovansky Stanislav
Acta Montanistica Slovaca , 1998,
Abstract: For this comparative assessment to factual possibilities of balance failure it is necessary to investigate a character and possible changes in individual elements of the system "rock - time", as well as their mutual interaction with rock burst origin and their course. Research observations after burst show that the influence of strong energy after rock burst, into the overlying impact click is present in a coal seam due to its higher pressure to a face (when compared with a relevant pressure answerring a final deformation after such burst). Certain "avalanche" in failures after burst could be characterized as a certain rank of individual particular phenomena.
The WRKY transcription factor superfamily: its origin in eukaryotes and expansion in plants
Yuanji Zhang, Liangjiang Wang
BMC Evolutionary Biology , 2005, DOI: 10.1186/1471-2148-5-1
Abstract: We searched all publicly available sequence data for WRKY genes. A single copy of the WRKY gene encoding two WRKY domains was identified from Giardia lamblia, a primitive eukaryote, Dictyostelium discoideum, a slime mold closely related to the lineage of animals and fungi, and the green alga Chlamydomonas reinhardtii, an early branching of plants. This ancestral WRKY gene seems to have duplicated many times during the evolution of plants, resulting in a large family in evolutionarily advanced flowering plants. In rice, the WRKY gene family consists of over 100 members. Analyses suggest that the C-terminal domain of the two-WRKY-domain encoding gene appears to be the ancestor of the single-WRKY-domain encoding genes, and that the WRKY domains may be phylogenetically classified into five groups. We propose a model to explain the WRKY family's origin in eukaryotes and expansion in plants.WRKY genes seem to have originated in early eukaryotes and greatly expanded in plants. The elucidation of the evolution and duplicative expansion of the WRKY genes should provide valuable information on their functions.Transcriptional control is a major mechanism whereby a cell or organism regulates its gene expression. Sequence-specific DNA-binding transcription regulators, one class of transcription factors [1], play an essential role in modulating the rate of transcription of specific target genes. In this way, they direct the temporal and spatial expressions necessary for normal development and proper response to physiological or environmental stimuli. Comparative genome analysis reveals that genes for transcription regulators are abundantly present in plant and animal genomes, and the evolution and diversity of eukaryotes seem to be related to the expansion of lineage-specific transcription regulator families [2].WRKY proteins are recently identified transcriptional regulators comprising a large gene family [3]. The first cDNA encoding a WRKY protein, SPF1, was cloned from sweet p
Ancient Origin of the Modern Deep-Sea Fauna  [PDF]
Ben Thuy, Andy S. Gale, Andreas Kroh, Michal Kucera, Lea D. Numberger-Thuy, Mike Reich, Sabine St?hr
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0046913
Abstract: The origin and possible antiquity of the spectacularly diverse modern deep-sea fauna has been debated since the beginning of deep-sea research in the mid-nineteenth century. Recent hypotheses, based on biogeographic patterns and molecular clock estimates, support a latest Mesozoic or early Cenozoic date for the origin of key groups of the present deep-sea fauna (echinoids, octopods). This relatively young age is consistent with hypotheses that argue for extensive extinction during Jurassic and Cretaceous Oceanic Anoxic Events (OAEs) and the mid-Cenozoic cooling of deep-water masses, implying repeated re-colonization by immigration of taxa from shallow-water habitats. Here we report on a well-preserved echinoderm assemblage from deep-sea (1000–1500 m paleodepth) sediments of the NE-Atlantic of Early Cretaceous age (114 Ma). The assemblage is strikingly similar to that of extant bathyal echinoderm communities in composition, including families and genera found exclusively in modern deep-sea habitats. A number of taxa found in the assemblage have no fossil record at shelf depths postdating the assemblage, which precludes the possibility of deep-sea recolonization from shallow habitats following episodic extinction at least for those groups. Our discovery provides the first key fossil evidence that a significant part of the modern deep-sea fauna is considerably older than previously assumed. As a consequence, most major paleoceanographic events had far less impact on the diversity of deep-sea faunas than has been implied. It also suggests that deep-sea biota are more resilient to extinction events than shallow-water forms, and that the unusual deep-sea environment, indeed, provides evolutionary stability which is very rarely punctuated on macroevolutionary time scales.
Developmental origin of chronic diseases: toxicological implication
tefan Bezek , Eduard Ujházy , Mojmír Mach , Jana Navarová , Michal Dubovicky
Interdisciplinary Toxicology , 2008, DOI: 10.2478/v10102-010-0029-8
Abstract: Human epidemiological and experimental animal studies show that suboptimal environments in fetal and neonatal life exerts a profound influence on physiological function and risk of disease in adult life. The molecular, cellular, metabolic, endocrine and physiological adaptations to intrauterine nutritional conditions result in permanent alterations of cellular proliferation and differentiation of tissues and organ systems, which in turn can manifest by pathological consequences or increased vulnerability to chronic diseases in adulthood. Intrauterine growth restriction (IUGR) due to intrauterine development derangements is considered the important factor in development of such diseases as essential hypertension, diabetes mellitus, ischemic diseases of the heart, osteoporosis, respiratory, neuropsychiatric and immune system diseases. An early life exposures to dietary and environmental exposures can have a important effect on epigenetic code, resulting in diseases developed later in life. The concept of the "developmental programming" and Developmental Origins of Adult Diseases (DOHaD) has become well accepted because of the compelling animal studies that have precisely defined the outcomes of specific exposures. The environmental pollullutants and other chemical toxicants may influence crucial cellular functions during critical periods of fetal development and permanently alter the structure or function of specific organ systems. Developmental epigenetics is believed to establish "adaptive" phenotypes to meet the demands of the later-life environment. Resulting phenotypes that match predicted later-life demands will promote health, while a high degree of mismatch will impede adaptability to later-life challenges and elevate disease risk. The rapid introduction of synthetic chemicals, environmental pollutants and medical interventions, may result in conflict with the programmed adaptive changes made during early development, and explain the alarming increases in some diseases.
Developmental Origin and Evolution of Bacteriocytes in the Aphid–Buchnera Symbiosis  [PDF]
Christian Braendle,Toru Miura,Ryan Bickel,Alexander W. Shingleton,Srinivas Kambhampati,David L. Stern
PLOS Biology , 2012, DOI: 10.1371/journal.pbio.0000021
Abstract: Symbiotic relationships between bacteria and insect hosts are common. Although the bacterial endosymbionts have been subjected to intense investigation, little is known of the host cells in which they reside, the bacteriocytes. We have studied the development and evolution of aphid bacteriocytes, the host cells that contain the endosymbiotic bacteria Buchnera aphidicola. We show that bacteriocytes of Acyrthosiphon pisum express several gene products (or their paralogues): Distal-less, Ultrabithorax/Abdominal-A, and Engrailed. Using these markers, we find that a subpopulation of the bacteriocytes is specified prior to the transmission of maternal bacteria to the embryo. In addition, we discovered that a second population of cells is recruited to the bacteriocyte fate later in development. We experimentally demonstrate that bacteriocyte induction and proliferation occur independently of B. aphidicola. Major features of bacteriocyte development, including the two-step recruitment of bacteriocytes, have been conserved in aphids for 80–150 million years. Furthermore, we have investigated two cases of evolutionary loss of bacterial symbionts: in one case, where novel extracellular, eukaryotic symbionts replaced the bacteria, the bacteriocyte is maintained; in another case, where symbionts are absent, the bacteriocytes are initiated but not maintained. The bacteriocyte represents an evolutionarily novel cell fate, which is developmentally determined independently of the bacteria. Three of five transcription factors we examined show novel expression patterns in bacteriocytes, suggesting that bacteriocytes may have evolved to express many additional transcription factors. The evolutionary transition to a symbiosis in which bacteria and an aphid cell form a functional unit, similar to the origin of plastids, has apparently involved extensive molecular adaptations on the part of the host cell.
Developmental Origin and Evolution of Bacteriocytes in the Aphid–Buchnera Symbiosis  [PDF]
Christian Braendle equal contributor,Toru Miura equal contributor,Ryan Bickel,Alexander W Shingleton,Srinivas Kambhampati,David L Stern
PLOS Biology , 2003, DOI: 10.1371/journal.pbio.0000021
Abstract: Symbiotic relationships between bacteria and insect hosts are common. Although the bacterial endosymbionts have been subjected to intense investigation, little is known of the host cells in which they reside, the bacteriocytes. We have studied the development and evolution of aphid bacteriocytes, the host cells that contain the endosymbiotic bacteria Buchnera aphidicola. We show that bacteriocytes of Acyrthosiphon pisum express several gene products (or their paralogues): Distal-less, Ultrabithorax/Abdominal-A, and Engrailed. Using these markers, we find that a subpopulation of the bacteriocytes is specified prior to the transmission of maternal bacteria to the embryo. In addition, we discovered that a second population of cells is recruited to the bacteriocyte fate later in development. We experimentally demonstrate that bacteriocyte induction and proliferation occur independently of B. aphidicola. Major features of bacteriocyte development, including the two-step recruitment of bacteriocytes, have been conserved in aphids for 80–150 million years. Furthermore, we have investigated two cases of evolutionary loss of bacterial symbionts: in one case, where novel extracellular, eukaryotic symbionts replaced the bacteria, the bacteriocyte is maintained; in another case, where symbionts are absent, the bacteriocytes are initiated but not maintained. The bacteriocyte represents an evolutionarily novel cell fate, which is developmentally determined independently of the bacteria. Three of five transcription factors we examined show novel expression patterns in bacteriocytes, suggesting that bacteriocytes may have evolved to express many additional transcription factors. The evolutionary transition to a symbiosis in which bacteria and an aphid cell form a functional unit, similar to the origin of plastids, has apparently involved extensive molecular adaptations on the part of the host cell.
Slipins: ancient origin, duplication and diversification of the stomatin protein family
Jasper B Green, J Peter W Young
BMC Evolutionary Biology , 2008, DOI: 10.1186/1471-2148-8-44
Abstract: We have constructed a comprehensive phylogeny of all 'stomatin-like' sequences that share a 150 amino acid domain. We show these proteins comprise an ancient family that arose early in prokaryotic evolution, and we propose a new nomenclature that reflects their phylogeny, based on the name "slipin" (stomatin-like protein). Within prokaryotes there are two distinct subfamilies that account for the two different origins of the eight eukaryotic stomatin subfamilies, one of which gave rise to eukaryotic SLP-2, renamed here "paraslipin". This was apparently acquired through the mitochondrial endosymbiosis and is widely distributed amongst the major kingdoms. The other prokaryotic subfamily gave rise to the ancestor of the remaining seven eukaryotic subfamilies. The highly diverged "alloslipin" subfamily is represented only by fungal, viral and ciliate sequences. The remaining six subfamilies, collectively termed "slipins", are confined to metazoa. Protostome stomatin, as well as a newly reported arthropod subfamily slipin-4, are restricted to invertebrate groups, whilst slipin-1 (previously SLP-1) is present in nematodes and higher metazoa. In vertebrates, the stomatin family expanded considerably, with at least two duplication events giving rise to podocin and slipin-3 subfamilies (previously SLP-3), with the retained ancestral sequence giving rise to vertebrate stomatin.Stomatin-like proteins have their origin in an ancient duplication event that occurred early on in the evolution of prokaryotes. By constructing a phylogeny of this family, we have identified and named a number of orthologous groups: these can now be used to infer function of stomatin subfamilies in a meaningful way.Human stomatin (hstomatin) was first identified as an integral membrane protein in human red blood cells [1-3]. It has since been shown to be expressed in many cell types and organisms, although hstomatin function remains unclear [4]. Loss of stomatin in humans is associated with a condition
Phylogenomic Analyses Reveal the Evolutionary Origin of the Inhibin α-Subunit, a Unique TGFβ Superfamily Antagonist  [PDF]
Jie Zhu,Edward L. Braun,Satomi Kohno,Monica Antenos,Eugene Y. Xu,Robert W. Cook,S. Jack Lin,Brandon C. Moore,Louis J. Guillette Jr,Theodore S. Jardetzky,Teresa K. Woodruff
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0009457
Abstract: Transforming growth factor-beta (TGFβ) homologues form a diverse superfamily that arose early in animal evolution and control cellular function through membrane-spanning, conserved serine-threonine kinases (RII and RI receptors). Activin and inhibin are related dimers within the TGFβ superfamily that share a common β-subunit. The evolution of the inhibin α-subunit created the only antagonist within the TGFβ superfamily and the only member known to act as an endocrine hormone. This hormone introduced a new level of complexity and control to vertebrate reproductive function. The novel functions of the inhibin α-subunit appear to reflect specific insertion-deletion changes within the inhibin β-subunit that occurred during evolution. Using phylogenomic analysis, we correlated specific insertions with the acquisition of distinct functions that underlie the phenotypic complexity of vertebrate reproductive processes. This phylogenomic approach presents a new way of understanding the structure-function relationships between inhibin, activin, and the larger TGFβ superfamily.
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