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Sample records for monotreme tachyglossus aculeatus

  1. Cyto- and chemoarchitecture of the amygdala of a monotreme, Tachyglossus aculeatus (the short-beaked echidna).

    Science.gov (United States)

    Ashwell, Ken W S; Hardman, Craig D; Paxinos, George

    2005-10-01

    We have examined the cyto- and chemoarchitecture of the temporal and extended amygdala in the brain of a monotreme (the short-beaked echidna Tachyglossus aculeatus) using Nissl and myelin staining, enzyme histochemistry for acetylcholine esterase and NADPH diaphorase, immunohistochemistry for calcium binding proteins (parvalbumin, calbindin and calretinin) and tyrosine hydroxylase. While the broad subdivisions of the eutherian temporal amygdala were present in the echidna brain, there were some noticeable differences. No immunoreactivity for parvalbumin or calretinin for somata was found in the temporal amygdala of the echidna. The nucleus of the lateral olfactory tract could not be definitively identified and the medial nucleus of amygdala appeared to be very small in the echidna. Calbindin immunoreactive neurons were most frequently found in the ventrolateral part of the lateral nucleus, intraamygdaloid parts of the bed nucleus of the stria terminalis and the lateral part of the central nucleus. Neurons strongly reactive for NADPH diaphorase with filling of the dendritic tree were found mainly scattered through the cortical, central and lateral subnuclei, while neurons showing only somata reactivity for NADPH diaphorase were concentrated in the basomedial and basolateral subnuclei. Most of the components of the extended amygdala of eutherians could also be identified in the echidna. Volumetric analysis indicated that the temporal amygdala in both the platypus and echidna is small compared to the same structure in both insectivores and primates, with the central and medial components of the temporal amygdala being particularly small.

  2. Cyto- and chemoarchitecture of the dorsal thalamus of the monotreme Tachyglossus aculeatus, the short beaked echidna.

    Science.gov (United States)

    Ashwell, Ken W S; Paxinos, George

    2005-12-01

    We have examined the cyto- and chemoarchitecture of the dorsal thalamus of the short beaked echidna (Tachyglossus aculeatus), using Nissl and myelin staining, immunoreactivity for parvalbumin, calbindin, calretinin and non-phosphorylated neurofilament protein (SMI-32 antibody), and histochemistry for acetylcholinesterase and NADPH diaphorase. Immunohistochemical methods revealed many nuclear boundaries, which were difficult to discern with Nissl staining. Parvalbumin immunoreactive somata were concentrated in the ventral posterior, reticular, posterior, lateral and medial geniculate nuclei, while parvalbumin immunoreactivity of the neuropil was present throughout all but the midline nuclei. Large numbers of calbindin immunoreactive somata were also found within the midline thalamic nuclei, and thalamic sensory relay nuclei. Immunoreactivity for calretinin was found in many small somata within the lateral geniculate "a" nucleus, with other labelled somata found in the lateral geniculate "b" nucleus, ventral posterior medial and ventral posterior lateral nuclei. Immunoreactivity with the SMI-32 antibody was largely confined to somata and neuropil within the thalamocortical relay nuclei (ventral posterior medial and lateral nuclei, lateral and medial geniculate nuclei and the posterior thalamic nucleus). In broad terms there were many similarities between the thalamus of this monotreme and that of eutheria (e.g. disposition of somatosensory thalamus, complementarity of parvalbumin and calbindin immunoreactive structures), but there were some unique features of the thalamus of the echidna. These include the relatively small size of the thalamic reticular nucleus and the preponderance of calbindin immunoreactive neurons over parvalbumin immunoreactive neurons in the ventral posterior nucleus.

  3. The pretectal nuclei in two monotremes: the short-beaked echidna (Tachyglossus aculeatus) and the platypus (Ornithorhynchus anatinus).

    Science.gov (United States)

    Ashwell, K W S; Paxinos, G

    2007-12-01

    We have examined the organization of the pretectal area in two monotremes (the short beaked echidna-Tachyglossus aculeatus, and the platypus-Ornithorhynchus anatinus) and compared it to that in the Wistar strain rat, using Nissl staining in conjunction with enzyme histochemistry (acetylcholinesterase and NADPH diaphorase) and immunohistochemistry for parvalbumin, calbindin, calretinin and non-phosphorylated neurofilament protein (SMI-32 antibody). We were able to identify distinct anterior, medial, posterior (now called tectal gray) and olivary pretectal nuclei as well as a nucleus of the optic tract, all with largely similar topographical and chemoarchitectonic features to the homologous regions in therian mammals. The positions of these pretectal nuclei correspond to the distributions of retinofugal terminals identified by other authors. The overall size of the pretectum in both monotremes was found to be at least comparable in size, if not larger than, the pretectum of representative therian mammals of similar brain and body size. Our findings suggest that the pretectum of these two monotreme species is comparable in both size and organization to that of eutherian mammals, and is more than just an undifferentiated area pretectalis. The presence of a differentiated pretectum with similar chemoarchitecture to therians in both living monotremes lends support to the idea that the stem mammal for both prototherian and therian lineages also had a differentiated pretectum. This in turn indicates that a differentiated pretectum appeared at least 125 million years ago in the mammalian lineage and that the stem mammal for proto- and eutherian lineages probably had similar pretectal nuclei to those identified in its descendants.

  4. On the morphology of the brachial plexus of the platypus (Ornithorhynchus anatinus) and the echidna (Tachyglossus aculeatus).

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    Koizumi, M; Sakai, T

    1997-04-01

    Four forelimbs of 3 platypuses and 3 forelimbs of 2 echidnas were examined to study the precise form of the brachial plexus and to clarify the structural characteristics of the brachial plexus in phylogeny. The spinal components contributing to the plexus (C4-T2) and the formation patterns of the 3 trunks of the plexus were the same as those generally observed in mammals. In the cranial half of the brachial plexus from C4, 5 and 6 in monotremes, division into the ventral bundle (lateral cord) and dorsal bundle (axillary nerve) is clear, as in other mammals. However, for monotremes, in the caudal half of the plexus from C7 and T1 (+T2) and the nerves arising from the caudal plexus there is no definite division into the ventral and dorsal bundles, which distribute to the flexor and extensor parts of the forelimbs, respectively. The lower trunk of the monotreme brachial plexus forms a cord which contains both ventral and dorsal components. This characteristic diverges from the generally accepted idea that the tetrapod limb plexus is divided clearly into 2 layers: a dorsal layer for extensors and a ventral layer for flexors of the limb. Considering the incomplete dorsoventral division of forelimb nerves in some reptiles and urodeles, the caudal half of the monotreme brachial plexus has characteristics in common with those of lower tetrapods.

  5. Lung development of monotremes: evidence for the mammalian morphotype.

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    Ferner, Kirsten; Zeller, Ulrich; Renfree, Marilyn B

    2009-02-01

    The reproductive strategies and the extent of development of neonates differ markedly between the three extant mammalian groups: the Monotremata, Marsupialia, and Eutheria. Monotremes and marsupials produce highly altricial offspring whereas the neonates of eutherian mammals range from altricial to precocial. The ability of the newborn mammal to leave the environment in which it developed depends highly on the degree of maturation of the cardio-respiratory system at the time of birth. The lung structure is thus a reflection of the metabolic capacity of neonates. The lung development in monotremes (Ornithorhynchus anatinus, Tachyglossus aculeatus), in one marsupial (Monodelphis domestica), and one altricial eutherian (Suncus murinus) species was examined. The results and additional data from the literature were integrated into a morphotype reconstruction of the lung structure of the mammalian neonate. The lung parenchyma of monotremes and marsupials was at the early terminal air sac stage at birth, with large terminal air sacs. The lung developed slowly. In contrast, altricial eutherian neonates had more advanced lungs at the late terminal air sac stage and postnatally, lung maturation proceeded rapidly. The mammalian lung is highly conserved in many respects between monotreme, marsupial, and eutherian species and the structural differences in the neonatal lungs can be explained mainly by different developmental rates. The lung structure of newborn marsupials and monotremes thus resembles the ancestral condition of the mammalian lung at birth, whereas the eutherian newborns have a more mature lung structure.

  6. Energy Homeostasis in Monotremes

    Directory of Open Access Journals (Sweden)

    Stewart C. Nicol

    2017-04-01

    Full Text Available In 1803, the French anatomist Étienne Geoffroy Saint-Hilaire decided that the newly described echidna and platypus should be placed in a separate order, the monotremes, intermediate between reptiles and mammals. The first physiological observations showed monotremes had low body temperatures and metabolic rates, and the consensus was that they were at a stage of physiological development intermediate between “higher mammals” and “lower vertebrates.” Subsequent studies demonstrated that platypuses and echidnas are capable of close thermoregulation in the cold although less so under hot conditions. Because the short-beaked echidna Tachyglossus aculeatus, may show very large daily variations in body temperature, as well as seasonal hibernation, it has been suggested that it may provide a useful model of protoendotherm physiology. Such analysis is complicated by the very significant differences in thermal relations between echidnas from different climates. In all areas female echidnas regulate Tb within 1°C during egg incubation. The lactation period is considered to be the most energetically expensive time for most female mammals but lactating echidnas showed no measurable difference in field metabolic rate from non-lactating females, while the lactation period is more than 200 days for Kangaroo Island echidnas but only 150 days in Tasmania. In areas with mild winters echidnas show reduced activity and shallow torpor in autumn and early winter, but in areas with cold winters echidnas enter true hibernation with Tb falling as low as 4.5°C. Monotremes do not possess brown adipose tissue and maximum rates of rewarming from hibernation in echidnas were only half those of marmots of the same mass. Although echidnas show very large seasonal variations in fat stores associated with hibernation there is no relationship between plasma leptin and adiposity. Leptin levels are lowest during post-reproductive fattening, supporting suggestions that in

  7. Development of the hypothalamus and pituitary in platypus (Ornithorhynchus anatinus) and short-beaked echidna (Tachyglossus aculeatus)

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    Ashwell, Ken W S

    2012-01-01

    The living monotremes (platypus and echidnas) are distinguished by the development of their young in a leathery-shelled egg, a low and variable body temperature and a primitive teat-less mammary gland. Their young are hatched in an immature state and must deal with the external environment, with all its challenges of hypothermia and stress, as well as sourcing nutrients from the maternal mammary gland. The Hill and Hubrecht embryological collections have been used to follow the structural development of the monotreme hypothalamus and its connections with the pituitary gland both in the period leading up to hatching and during the lactational phase of development, and to relate this structural maturation to behavioural development. In the incubation phase, development of the hypothalamus proceeds from closure of the anterior neuropore to formation of the lateral hypothalamic zone and putative medial forebrain bundle. Some medial zone hypothalamic nuclei are emerging at the time of hatching, but these are poorly differentiated and periventricular zone nuclei do not appear until the first week of post-hatching life. Differentiation of the pituitary is also incomplete at hatching, epithelial cords do not develop in the pars anterior until the first week, and the hypothalamo-neurohypophyseal tract does not appear until the second week of post-hatching life. In many respects, the structure of the hypothalamus and pituitary of the newly hatched monotreme is similar to that seen in newborn marsupials, suggesting that both groups rely solely on lateral hypothalamic zone nuclei for whatever homeostatic mechanisms they are capable of at birth/hatching. PMID:22512474

  8. Distinct development of peripheral trigeminal pathways in the platypus (Ornithorhynchus anatinus) and short-beaked echidna (Tachyglossus aculeatus).

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    Ashwell, Ken W S; Hardman, Craig D; Giere, Peter

    2012-01-01

    The extant monotremes (platypus and echidnas) are believed to all be capable of electroreception in the trigeminal pathways, although they differ significantly in the number and distribution of electroreceptors. It has been argued by some authors that electroreception was first developed in an aquatic environment and that echidnas are descended from a platypus-like ancestor that invaded an available terrestrial habitat. If this were the case, one would expect the developmental trajectories of the trigeminal pathways to be similar in the early stages of platypus and short-beaked echidna development, with structural divergence occurring later. We examined the development of the peripheral trigeminal pathway from snout skin to trigeminal ganglion in sectioned material in the Hill and Hubrecht collections to test for similarities and differences between the two during the development from egg to adulthood. Each monotreme showed a characteristic and different pattern of distribution of developing epidermal sensory gland specializations (electroreceptor primordia) from the time of hatching. The cross-sectional areas of the trigeminal divisions and the volume of the trigeminal ganglion itself were also very different between the two species at embryonic ages, and remained consistently different throughout post-hatching development. Our findings indicate that the trigeminal pathways in the short-beaked echidna and the platypus follow very different developmental trajectories from the earliest ages. These findings are more consistent with the notion that the platypus and echidna have both diverged from an ancestor with rudimentary electroreception and/or trigeminal specialization, rather than the contention that the echidna is derived from a platypus-like ancestor. Copyright © 2011 S. Karger AG, Basel.

  9. Development of the dorsal and ventral thalamus in platypus (Ornithorhynchus anatinus) and short-beaked echidna (Tachyglossus aculeatus).

    Science.gov (United States)

    Ashwell, Ken W S

    2012-04-01

    The living monotremes (platypus and echidnas) are distinguished from therians as well as each other in part by the unusual structure of the thalamus in each. In particular, the platypus has an enlarged ventral posterior (VP) nucleus reflecting the great behavioural importance of trigeminosensation and electroreception. The embryological collections of the Museum für Naturkunde in Berlin were used to analyse the development of the dorsal thalamus and ventral thalamus (prethalamus) in both species. Prosomeric organization of the forebrain emerged at 6 mm crown-rump length (CRL), but thalamic neurogenesis did not commence until about 8-9 mm CRL. Distinctive features of the dorsal thalamus in the two species began to emerge after hatching (about 14-15 mm CRL). During the first post-hatching week, dense clusters of granular cells aggregated to form the VP of the platypus, whereas the VP complex of the echidna remained smaller and divided into distinct medial and lateral divisions. At the end of the first post-hatching week, the thalamocortical tract was much larger in the platypus than the echidna. The dorsal thalamus of the platypus is essentially adult-like by the sixth week of post-hatching life. The similar appearance of the dorsal thalamus in the two species until the time of hatching, followed by the rapid expansion of the VP in the platypus, is most consistent with ancestral platypuses having undergone changes in the genetic control of thalamic neurogenesis to produce a large VP for trigeminal electroreception after the divergence of the two lineages of monotreme.

  10. Sensory receptors in monotremes.

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    Proske, U; Gregory, J E; Iggo, A

    1998-01-01

    This is a summary of the current knowledge of sensory receptors in skin of the bill of the platypus, Ornithorhynchus anatinus, and the snout of the echidna, Tachyglossus aculeatus. Brief mention is also made of the third living member of the monotremes, the long-nosed echidna, Zaglossus bruijnii. The monotremes are the only group of mammals known to have evolved electroreception. The structures in the skin responsible for the electric sense have been identified as sensory mucous glands with an expanded epidermal portion that is innervated by large-diameter nerve fibres. Afferent recordings have shown that in both platypuses and echidnas the receptors excited by cathodal (negative) pulses and inhibited by anodal (positive) pulses. Estimates give a total of 40,000 mucous sensory glands in the upper and lower bill of the platypus, whereas there are only about 100 in the tip of the echidna snout. Recording of electroreceptor-evoked activity from the brain of the platypus have shown that the largest area dedicated to somatosensory input from the bill, S1, shows alternating rows of mechanosensory and bimodal neurons. The bimodal neurons respond to both electrosensory and mechanical inputs. In skin of the platypus bill and echidna snout, apart from the electroreceptors, there are structures called push rods, which consist of a column of compacted cells that is able to move relatively independently of adjacent regions of skin. At the base of the column are Merkel cell complexes, known to be type I slowly adapting mechanoreceptors, and lamellated corpuscles, probably vibration receptors. It has been speculated that the platypus uses its electric sense to detect the electromyographic activity from moving prey in the water and for obstacle avoidance. Mechanoreceptors signal contact with the prey. For the echidna, a role for the electrosensory system has not yet been established during normal foraging behaviour, although it has been shown that it is able to detect the presence

  11. The claustrum is not missing from all monotreme brains.

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    Ashwell, Ken W S; Hardman, Craig; Paxinos, George

    2004-01-01

    Many authors have reported that the claustrum, which comprises the insular claustrum and the endopiriform nucleus, is missing from the monotreme forebrain. We used Nissl and myelin staining in conjunction with enzyme histochemistry for acetylcholinesterase and immunohistochemistry for parvalbumin, calbindin, calretinin and tyrosine hydroxylase to examine the brains of two monotremes, the short-beaked echidna (Tachyglossus aculeatus) and the platypus (Ornithorhynchus anatinus). We found that although the insular claustrum is a small structure in the echidna brain, it is nevertheless clearly present as loosely clustered neurons embedded in the white matter ventrolateral to the putamen and deep to the piriform and entorhinal cortices. Neurons in this region share the chemical features of the adjacent cortex (presence of a similar proportion of parvalbumin immunoreactive neurons and minimal activity for acetylcholinesterase and tyrosine hydroxylase), unlike the adjacent putamen and ventral pallidum. A putative endopiriform nucleus can be identified in the interior of the piriform lobe of the echidna as calretinin immunoreactive neurons embedded within the white matter. The situation is much less clear in the platypus, but our data suggest that there may be an insular claustrum deep to frontal cortex, separated from layer VI by only a thin layer of white matter. We could not identify an endopiriform nucleus in our platypus material. Our findings indicate that presence of the claustrum cannot be considered a feature confined to therian mammals and lend weight to arguments that this structure was present in the ancestral mammalian brain.

  12. Electroreception in monotremes.

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    Pettigrew, J D

    1999-05-01

    I will briefly review the history of the bill sense of the platypus, a sophisticated combination of electroreception and mechanoreception that coordinates information about aquatic prey provided from the bill skin mechanoreceptors and electroreceptors, and provide an evolutionary account of electroreception in the three extant species of monotreme (and what can be inferred of their ancestors). Electroreception in monotremes is compared and contrasted with the extensive body of work on electric fish, and an account of the central processing of mechanoreceptive and electroreceptive input in the somatosensory neocortex of the platypus, where sophisticated calculations seem to enable a complete three-dimensional fix on prey, is given.

  13. Conditional same/different concept learning in the short-beaked echidna (Tachyglossus aculeatus).

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    Russell, Fiona; Burke, Darren

    2016-01-01

    Echidnas have evolved separately from other mammalian groups for around 200 million years and incorporate a mixture of reptilian and mammalian features. Because of these attributes, they have historically been considered "primitive" animals. However, they have successfully adapted to a wide variety of ecological niches and their neurophysiology demonstrates a number of unusual and apparently sophisticated characteristics, including a relatively large brain and cerebral cortex and a comparatively massive frontal cortex. Studies of learning in the echidna have thus far been limited to only a handful of experiments which demonstrated relatively basic abilities such as forming a position habit in a T-maze, successive habit-reversal learning, and simple visual and instrumental discrimination. This study aimed to expand on these results and test the "primitive" echidna on what are generally considered more advanced cognitive tasks-same/different and conditional same/different concept learning. The results demonstrated that echidnas are able to discriminate on the basis of a relational same/different concept, using simultaneously presented multi-element stimuli, and transfer that discrimination to novel stimuli. After further training, they were then able to repeat the performance when the correct choice was conditional on the background color of the stimulus panels.

  14. Taxonomy Icon Data: Australian echidna [Taxonomy Icon

    Lifescience Database Archive (English)

    Full Text Available Australian echidna Tachyglossus aculeatus Chordata/Vertebrata/Mammalia/Prototheria Tachygloss...us_aculeatus_L.png Tachyglossus_aculeatus_NL.png Tachyglossus_aculeatus_S.png Tachyglossus_aculeat...us_NS.png http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Tachyglossus+aculeatus&t=L http://biosciencedbc.j...p/taxonomy_icon/icon.cgi?i=Tachyglossus+aculeatus&t=NL http://biosciencedbc.jp/ta...xonomy_icon/icon.cgi?i=Tachyglossus+aculeatus&t=S http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Tachyglossus+aculeatus&t=NS ...

  15. Monotreme lactation protein is highly expressed in monotreme milk and provides antimicrobial protection.

    Science.gov (United States)

    Enjapoori, Ashwantha Kumar; Grant, Tom R; Nicol, Stewart C; Lefèvre, Christophe M; Nicholas, Kevin R; Sharp, Julie A

    2014-09-22

    Monotremes (platypus and echidna) are the descendants of the oldest ancestor of all extant mammals distinguished from other mammals by mode of reproduction. Monotremes lay eggs following a short gestation period and after an even briefer incubation period, altricial hatchlings are nourished over a long lactation period with milk secreted by nipple-less mammary patches located on the female's abdomen. Milk is the sole source of nutrition and immune protection for the developing young until weaning. Using transcriptome and mass spectrometry analysis of milk cells and milk proteins, respectively, a novel Monotreme Lactation Protein (MLP) was identified as a major secreted protein in milk. We show that platypus and short-beaked echidna MLP genes show significant homology and are unique to monotremes. The MLP transcript was shown to be expressed in a variety of tissues; however, highest expression was observed in milk cells and was expressed constitutively from early to late lactation. Analysis of recombinant MLP showed that it is an N-linked glycosylated protein and biophysical studies predicted that MLP is an amphipathic, α-helical protein, a typical feature of antimicrobial proteins. Functional analysis revealed MLP antibacterial activity against both opportunistic pathogenic Staphylococcus aureus and commensal Enterococcus faecalis bacteria but showed no effect on Escherichia coli, Pseudomonas aeruginosa, Staphylococcus epidermidis, and Salmonella enterica. Our data suggest that MLP is an evolutionarily ancient component of milk-mediated innate immunity absent in other mammals. We propose that MLP evolved specifically in the monotreme lineage supporting the evolution of lactation in these species to provide bacterial protection, at a time when mammals lacked nipples.

  16. Monotreme Lactation Protein Is Highly Expressed in Monotreme Milk and Provides Antimicrobial Protection

    Science.gov (United States)

    Enjapoori, Ashwantha Kumar; Grant, Tom R.; Nicol, Stewart C.; Lefèvre, Christophe M.; Nicholas, Kevin R.; Sharp, Julie A.

    2014-01-01

    Monotremes (platypus and echidna) are the descendants of the oldest ancestor of all extant mammals distinguished from other mammals by mode of reproduction. Monotremes lay eggs following a short gestation period and after an even briefer incubation period, altricial hatchlings are nourished over a long lactation period with milk secreted by nipple-less mammary patches located on the female’s abdomen. Milk is the sole source of nutrition and immune protection for the developing young until weaning. Using transcriptome and mass spectrometry analysis of milk cells and milk proteins, respectively, a novel Monotreme Lactation Protein (MLP) was identified as a major secreted protein in milk. We show that platypus and short-beaked echidna MLP genes show significant homology and are unique to monotremes. The MLP transcript was shown to be expressed in a variety of tissues; however, highest expression was observed in milk cells and was expressed constitutively from early to late lactation. Analysis of recombinant MLP showed that it is an N-linked glycosylated protein and biophysical studies predicted that MLP is an amphipathic, α-helical protein, a typical feature of antimicrobial proteins. Functional analysis revealed MLP antibacterial activity against both opportunistic pathogenic Staphylococcus aureus and commensal Enterococcus faecalis bacteria but showed no effect on Escherichia coli, Pseudomonas aeruginosa, Staphylococcus epidermidis, and Salmonella enterica. Our data suggest that MLP is an evolutionarily ancient component of milk-mediated innate immunity absent in other mammals. We propose that MLP evolved specifically in the monotreme lineage supporting the evolution of lactation in these species to provide bacterial protection, at a time when mammals lacked nipples. PMID:25245409

  17. Tracing Monotreme Venom Evolution in the Genomics Era

    Science.gov (United States)

    Whittington, Camilla M.; Belov, Katherine

    2014-01-01

    The monotremes (platypuses and echidnas) represent one of only four extant venomous mammalian lineages. Until recently, monotreme venom was poorly understood. However, the availability of the platypus genome and increasingly sophisticated genomic tools has allowed us to characterize platypus toxins, and provides a means of reconstructing the evolutionary history of monotreme venom. Here we review the physiology of platypus and echidna crural (venom) systems as well as pharmacological and genomic studies of monotreme toxins. Further, we synthesize current ideas about the evolution of the venom system, which in the platypus is likely to have been retained from a venomous ancestor, whilst being lost in the echidnas. We also outline several research directions and outstanding questions that would be productive to address in future research. An improved characterization of mammalian venoms will not only yield new toxins with potential therapeutic uses, but will also aid in our understanding of the way that this unusual trait evolves. PMID:24699339

  18. Formation and Dissociation of Sperm Bundles in Monotremes.

    Science.gov (United States)

    Nixon, Brett; Ecroyd, Heath; Dacheux, Jean-Louis; Dacheux, Francoise; Labas, Valerie; Johnston, Steve D; Jones, Russell C

    2016-10-01

    Because monotremes are the earliest offshoot of the mammalian lineage, the platypus and short-beaked echidna were studied as model animals to assess the origin and biological significance of adaptations considered unique to therian mammals: epididymal sperm maturation and subsequent capacitation. We show that spermatozoa from both species assemble into bundles of approximately 100 cells during passage through the epididymis and that an epididymal protein-secreted protein, acidic, cysteine-rich (osteonectin; SPARC)-is involved in bundle formation. The bundles persisted during incubation in vitro for at least 1 h under conditions that capacitate therian spermatozoa, and then underwent a time-dependent dissociation to release spermatozoa capable of fertilization. Only after this dissociation could the spermatozoa bind to the perivitelline membrane of a hen's egg, display an altered form of motility reminiscent of hyperactivation, and be induced to undergo an acrosome reaction. It is concluded that the development of sperm bundles in the monotreme epididymis mandates that they require a time-dependent process to be capable of fertilizing an ovum. However, because this functional end point was achieved without overt changes in protein tyrosine phosphorylation (a hallmark of capacitation in therians), it is concluded that the process in monotremes is distinctly different from capacitation in therian mammals. © 2016 by the Society for the Study of Reproduction, Inc.

  19. Discovery of novel secondary metabolites in Aspergillus aculeatus

    DEFF Research Database (Denmark)

    Petersen, Lene Maj; Holm, Dorte Koefoed; Gotfredsen, Charlotte Held

    2012-01-01

    of the industrially important black Aspergillus Aspergillus aculeatus by UHPLC-DAD-HRMS has identified several SMs already known from this organism. However, several compounds could not be unambiguously dereplicated wherefore some have been selected, purified and structure elucidated by 1D and 2D NMR spectroscopy...

  20. Identification and functional characterization of a novel monotreme- specific antibacterial protein expressed during lactation.

    Directory of Open Access Journals (Sweden)

    Swathi Bisana

    Full Text Available Monotremes are the only oviparous mammals and exhibit a fascinating combination of reptilian and mammalian characters. They represent a component of synapsidal reproduction by laying shelled eggs which are incubated outside the mother's body. This is accompanied by a prototherian lactation process, marking them as representatives of early mammals. The only extant monotremes are the platypus, and the short- and long- beaked echidnas, and their distributions are limited to Australia and New Guinea. Apart for a short weaning period, milk is the sole source of nutrition and protection for the hatchlings which are altricial and immunologically naive. The duration of lactation in these mammals is prolonged relative to the gestational length and period of incubation of eggs. Much of the development of monotreme young occurs in the non-sterile ex-utero environment. Therefore the role of milk in the growth, development and disease protection of the young is of significant interest. By sequencing the cDNA of cells harvested from monotreme milk, we have identified a novel monotreme- specific transcript, and the corresponding gene was designated as the EchAMP. The expression profile of this gene in various tissues revealed that it is highly expressed in milk cells. The peptides corresponding to the EchAMP protein have been identified in a sample of echidna milk In silico analysis indicated putative antimicrobial potential for the cognate protein of EchAMP. This was further confirmed by in vitro assays using a host of bacteria. Interestingly, EchAMP did not display any activity against a commensal gut floral species. These results support the hypothesis of enhancement of survival of the young by antimicrobial bioactives of mammary gland origin and thus emphasize the protective, non- nutritional role of milk in mammals.

  1. The mitochondrial genome of a monotreme--the platypus (Ornithorhynchus anatinus).

    Science.gov (United States)

    Janke, A; Gemmell, N J; Feldmaier-Fuchs, G; von Haeseler, A; Pääbo, S

    1996-02-01

    The complete nucleotide sequence of the mitochondrial genome of a platypus (Ornithorhynchus anatinus) was determined. Its overall genomic organization is similar to that of placental mammals, Xenopus laevis, and fishes. However, it contains an apparently noncoding sequence of 88 base pairs located between the genes for tRNA(Leu)(UUR) and ND1. The base composition of this sequence and its conservation among monotremes, as well as the existence of a transcript from one of the strands, indicate that it may have a hitherto-unknown function. When the protein-coding sequences are used to reconstruct a phylogeny of mammals, the data suggest that monotremes and marsupials are sister groups and thus that placental mammals represent the most ancient divergence among mammals.

  2. The X factor: X chromosome dosage compensation in the evolutionarily divergent monotremes and marsupials.

    Science.gov (United States)

    Whitworth, Deanne J; Pask, Andrew J

    2016-08-01

    Marsupials and monotremes represent evolutionarily divergent lineages from the majority of extant mammals which are eutherian, or placental, mammals. Monotremes possess multiple X and Y chromosomes that appear to have arisen independently of eutherian and marsupial sex chromosomes. Dosage compensation of X-linked genes occurs in monotremes on a gene-by-gene basis, rather than through chromosome-wide silencing, as is the case in eutherians and marsupials. Specifically, studies in the platypus have shown that for any given X-linked gene, a specific proportion of nuclei within a cell population will silence one locus, with the percentage of cells undergoing inactivation at that locus being highly gene-specific. Hence, it is perhaps not surprising that the expression level of X-linked genes in female platypus is almost double that in males. This is in contrast to the situation in marsupials where one of the two X chromosomes is inactivated in females by the long non-coding RNA RSX, a functional analogue of the eutherian XIST. However, marsupial X chromosome inactivation differs from that seen in eutherians in that it is exclusively the paternal X chromosome that is silenced. In addition, marsupials appear to have globally upregulated X-linked gene expression in both sexes, thus balancing their expression levels with those of the autosomes, a process initially proposed by Ohno in 1967 as being a fundamental component of the X chromosome dosage compensation mechanism but which may not have evolved in eutherians.

  3. Characterization of Aspergillus aculeatus β-glucosidase 1 accelerating cellulose hydrolysis with Trichoderma cellulase system

    National Research Council Canada - National Science Library

    Baba, Yutaro; Sumitani, Jun-ichi; Tani, Shuji; Kawaguchi, Takashi

    2015-01-01

    Aspergillus aculeatus β-glucosidase 1 (AaBGL1), which promotes cellulose hydrolysis by Trichoderma cellulase system, was characterized and compared some properties to a commercially supplied orthologue in A. niger (AnBGL...

  4. Chromosomal aberrations found in Paracalanus aculeatus (Giesbrecht) at the time of solar eclipse

    Digital Repository Service at National Institute of Oceanography (India)

    Goswami, U.; Goswami, S.C.

    Chromosomal aberrations in the form of an unequal heteromorphic homologous pair and a supernumerary chromosome were observed in the gonad of a copepod - @iParacalanus aculeatus@@ after being exposed to the total solar eclipse of Feb. 16, 1980...

  5. Dereplication Guided Discovery of Secondary Metabolites of Mixed Biosynthetic Origin from Aspergillus aculeatus

    DEFF Research Database (Denmark)

    Petersen, Lene Maj; Hoeck, Casper; Frisvad, Jens Christian;

    2014-01-01

    Investigation of the chemical profile of the industrially important black filamentous fungus Aspergillus aculeatus by UHPLC-DAD-HRMS and subsequent dereplication has led to the discovery of several novel compounds. Isolation and extensive 1D and 2D NMR spectroscopic analyses allowed for structura...... Candida albicans, however all showed only weak or no activity. Aspergillus aculeatus IBT 21030 was additionally shown to be capable of producing sclerotia. Examination of the sclerotia revealed a highly regulated production of metabolites in these morphological structures....

  6. Cain and Abel reloaded? Kin recognition and male-male aggression in three-spined sticklebacks Gasterosteus aculeatus L.

    Science.gov (United States)

    Mehlis, M; Bakker, T C M; Langen, K; Frommen, J G

    2009-11-01

    The influence of relatedness on male-male aggression was tested in three-spined sticklebacks Gasterosteus aculeatus. The intensity of aggression against brothers and non-kin males did not differ significantly, indicating that kin recognition plays at most a minor role in aggressive interactions between male G. aculeatus.

  7. Combined molecular and biochemical approach identifies Aspergillus japonicus and Aspergillus aculeatus as two species

    DEFF Research Database (Denmark)

    Parenicova, L.; Skouboe, P.; Frisvad, Jens Christian

    2001-01-01

    We examined nine Aspergillus japonicus isolates and 10 Aspergillus aculeatus isolates by using molecular and biochemical markers, including DNA sequences of the ITS1-5.8S rRNA gene-ITS2 region, restriction fragment length polymorphisms (RFLP), and secondary-metabolite profiles. The DNA sequence...... of the internal transcribed spacers (ITS1 and ITS2) and the 5.8S rRNA gene could not be used to distinguish between A. japonicus and A. aculeatus but did show that these two taxa are more closely related to each other than to other species of black aspergilli. Aspergillus niger pyruvate kinase (pkiA) and pectin...

  8. Combined molecular and biochemical approach identifies Aspergillus japonicus and Aspergillus aculeatus as two species

    DEFF Research Database (Denmark)

    Parenicova, L.; Skouboe, P.; Frisvad, Jens Christian

    2001-01-01

    lyase A (pelA) and Agaricus bisporus 28S rRNA genes, which were used as probes in the RFLP analysis, revealed clear polymorphism between these two taxa. The A. niger pkiA and pelA probes placed six strains in an A. japonicus group and 12 isolates in an A. aculeatus group, which exhibited intraspecific...

  9. Peroxisomes in intestinal and gallbladder epithelial cells of the stickleback, Gasterosteus aculeatus L. (Teleostei)

    NARCIS (Netherlands)

    Ruiter, A.J.H. de; Veenhuis, M.; Wendelaar Bonga, S.E.

    1988-01-01

    The occurrence of microbodies in the epithelial cells of the intestine and gallbladder of the stickleback, Gasterosteus aculeatus L., is described. In the intestine the organelles are predominantly located in the apical and perinuclear zone of the cells and may contain small crystalline cores. In ga

  10. Echidna venom gland transcriptome provides insights into the evolution of monotreme venom.

    Directory of Open Access Journals (Sweden)

    Emily S W Wong

    Full Text Available Monotremes (echidna and platypus are egg-laying mammals. One of their most unique characteristic is that males have venom/crural glands that are seasonally active. Male platypuses produce venom during the breeding season, delivered via spurs, to aid in competition against other males. Echidnas are not able to erect their spurs, but a milky secretion is produced by the gland during the breeding season. The function and molecular composition of echidna venom is as yet unknown. Hence, we compared the deeply sequenced transcriptome of an in-season echidna crural gland to that of a platypus and searched for putative venom genes to provide clues into the function of echidna venom and the evolutionary history of monotreme venom. We found that the echidna venom gland transcriptome was markedly different from the platypus with no correlation between the top 50 most highly expressed genes. Four peptides found in the venom of the platypus were detected in the echidna transcriptome. However, these genes were not highly expressed in echidna, suggesting that they are the remnants of the evolutionary history of the ancestral venom gland. Gene ontology terms associated with the top 100 most highly expressed genes in echidna, showed functional terms associated with steroidal and fatty acid production, suggesting that echidna "venom" may play a role in scent communication during the breeding season. The loss of the ability to erect the spur and other unknown evolutionary forces acting in the echidna lineage resulted in the gradual decay of venom components and the evolution of a new role for the crural gland.

  11. Echidna venom gland transcriptome provides insights into the evolution of monotreme venom.

    Science.gov (United States)

    Wong, Emily S W; Nicol, Stewart; Warren, Wesley C; Belov, Katherine

    2013-01-01

    Monotremes (echidna and platypus) are egg-laying mammals. One of their most unique characteristic is that males have venom/crural glands that are seasonally active. Male platypuses produce venom during the breeding season, delivered via spurs, to aid in competition against other males. Echidnas are not able to erect their spurs, but a milky secretion is produced by the gland during the breeding season. The function and molecular composition of echidna venom is as yet unknown. Hence, we compared the deeply sequenced transcriptome of an in-season echidna crural gland to that of a platypus and searched for putative venom genes to provide clues into the function of echidna venom and the evolutionary history of monotreme venom. We found that the echidna venom gland transcriptome was markedly different from the platypus with no correlation between the top 50 most highly expressed genes. Four peptides found in the venom of the platypus were detected in the echidna transcriptome. However, these genes were not highly expressed in echidna, suggesting that they are the remnants of the evolutionary history of the ancestral venom gland. Gene ontology terms associated with the top 100 most highly expressed genes in echidna, showed functional terms associated with steroidal and fatty acid production, suggesting that echidna "venom" may play a role in scent communication during the breeding season. The loss of the ability to erect the spur and other unknown evolutionary forces acting in the echidna lineage resulted in the gradual decay of venom components and the evolution of a new role for the crural gland.

  12. Non-parallel divergence across freshwater and marine three-spined stickleback Gasterosteus aculeatus populations.

    Science.gov (United States)

    Pujolar, J M; Ferchaud, A L; Bekkevold, D; Hansen, M M

    2017-07-01

    This work investigated whether multiple freshwater populations of three-spined stickleback Gasterosteus aculeatus in different freshwater catchments in the Jutland Peninsula, Denmark, derived from the same marine populations show repeated adaptive responses. A total of 327 G. aculeatus collected at 13 sampling locations were screened for genetic variation using a combination of 70 genes putatively under selection and 26 neutral genes along with a marker linked to the ectodysplasin gene (eda), which is strongly correlated with plate armour morphs in the species. A highly significant genetic differentiation was found that was higher among different freshwater samples than between marine-freshwater samples. Tests for selection between marine and freshwater populations showed a very low degree of parallelism and no single nucleotide polymorphism was detected as outlier in all freshwater-marine pairwise comparisons, including the eda. This suggests that G. aculeatus is not necessarily the prime example of parallel local adaptation suggested in much of the literature and that important exceptions exist (i.e. the Jutland Peninsula). While marine populations in the results described here showed a high phenotype-genotype correlation at eda, a low association was found for most of the freshwater populations. The most extreme case was found in the freshwater Lake Hald where all low-plated phenotypes were either homozygotes for the allele supposed to be associated with completely plated morphs or heterozygotes, but none were homozygotes for the putative low-plated allele. Re-examination of data from seven G. aculeatus studies agrees in showing a high but partial association between phenotype-genotype at eda in G. aculeatus freshwater populations and that mismatches occur everywhere in the European regions studied (higher in some areas, i.e. Denmark). This is independent of the eda marker used. © 2017 The Fisheries Society of the British Isles.

  13. The hypothalamic supraoptic and paraventricular nuclei of the echidna and platypus.

    Science.gov (United States)

    Ashwell, Ken W S; Lajevardi, Shahab-Eddin; Cheng, Gang; Paxinos, George

    2006-01-01

    The monotremes are an intriguing group of mammals that have major differences in their reproductive physiology and lactation from therian mammals. Monotreme young hatch from leathery skinned eggs and are nourished by milk secreted onto areolae rather than through nipples. Parturition and lactation are in part controlled through the paraventricular and supraoptic nuclei of the hypothalamus. We have used Nissl staining, enzyme histochemistry, immunohistochemistry for tyrosine hydroxylase, calbindin, oxytocin, neurophysin and non-phosphorylated neurofilament protein, and carbocyanine dye tracing techniques to examine the supraoptic and paraventricular nuclei and the course of the hypothalamo-neurohypophysial tract in two monotremes: the short-beaked echidna (Tachyglossus aculeatus) and the platypus (Ornithorhynchus anatinus). In both monotremes, the supraoptic nucleus consisted of loosely packed neurons, mainly in the retrochiasmatic position. In the echidna, the paraventricular nucleus was quite small, but had similar chemoarchitectural features to therians. In the platypus, the paraventricular nucleus was larger and appeared to be part of a stream of magnocellular neurons extending from the paraventricular nucleus to the retrochiasmatic supraoptic nucleus. Immunohistochemistry for non-phosphorylated neurofilament protein and carbocyanine dye tracing suggested that hypothalamo-neurohypophysial tract neurons in the echidna lie mainly in the retrochiasmatic supraoptic and lateral hypothalamic regions, but most neurophysin and oxytocin immunoreactive neurons in the echidna were found in the paraventricular, lateral hypothalamus and supraoptic nuclei and most oxytocinergic neurons in the platypus were distributed in a band from the paraventricular nucleus to the retrochiasmatic supraoptic nucleus. The small size of the supraoptic nucleus in the two monotremes might reflect functional aspects of monotreme lactation.

  14. CJ-15,183, a new inhibitor of squalene synthase produced by a fungus, Aspergillus aculeatus.

    Science.gov (United States)

    Watanabe, S; Hirai, H; Ishiguro, M; Kambara, T; Kojima, Y; Matsunaga, T; Nishida, H; Suzuki, Y; Sugiura, A; Harwood, H J; Huang, L H; Kojima, N

    2001-11-01

    A new squalene synthase (SSase) inhibitor, CJ-15,183 (I) was isolated from the fermentation broth of a fungus, Aspergillus aculeatus CL38916. The compound potently inhibited rat liver and Candida albicans microsomal SSases and also inhibited the human enzyme. It also showed antifungal activities against filamentous fungi and a yeast. The structure was determined to be an aliphatic tetracarboxylic acid compound consisting of an alkyl gamma-lactone, malic acid and isocitric acid moieties by spectroscopic studies.

  15. Spermiogenesis and spermiation in a monotreme mammal, the platypus, Ornithorhynchus anatinus.

    Science.gov (United States)

    Lin, M; Jones, R C

    2000-02-01

    Spermatogenesis in the platypus (Ornithorhynchus anatinus) is of considerable biological interest as the structure of its gametes more closely resemble that of reptiles and birds than marsupial or eutherian mammals. The ultrastructure of 16 steps of spermatid development is described and provides a basis for determining the kinetics of spermatogenesis. Steps 1-3 correspond to the Golgi phase of spermatid development, steps 4-8 correspond to the cap phase, steps 9-12 are the acrosomal phase, and steps 13-16 are the maturation phase. Acrosomal development follows the reptilian model and no acrosomal granule is formed. Most other features of spermiogenesis are similar to processes in reptiles and birds. However, some are unique to mammals. For example, a thin, lateral margin of the acrosome of platypus sperm expands over the nucleus as in other mammals, and more than in reptiles and birds. Also, a tubulobulbar complex develops around the spermatid head, a feature which appears to be unique to mammals. Further, during spermiation the residual body is released from the caudal end of the nucleus of platypus sperm leaving a cytoplasmic droplet located at the proximal end of the middle piece as in marsupial and eutherian mammals. Other features of spermiogenesis in platypus appear to be unique to monotremes. For example, nuclear condensation involves the formation of a layer of chromatin granules under the nucleolemma, and development of the fibrous sheath of the principal piece starts much later in the platypus than in birds or eutherian mammals.

  16. In vitro leukocyte response of three-spined sticklebacks (Gasterosteus aculeatus) to helminth parasite antigens.

    Science.gov (United States)

    Franke, Frederik; Rahn, Anna K; Dittmar, Janine; Erin, Noémie; Rieger, Jennifer K; Haase, David; Samonte-Padilla, Irene E; Lange, Joseph; Jakobsen, Per J; Hermida, Miguel; Fernández, Carlos; Kurtz, Joachim; Bakker, Theo C M; Reusch, Thorsten B H; Kalbe, Martin; Scharsack, Jörn P

    2014-01-01

    Helminth parasites of teleost fish have evolved strategies to evade and manipulate the immune responses of their hosts. Responsiveness of fish host immunity to helminth antigens may therefore vary depending on the degree of host-parasite counter-adaptation. Generalist parasites, infective for a number of host species, might be unable to adapt optimally to the immune system of a certain host species, while specialist parasites might display high levels of adaptation to a particular host species. The degree of adaptations may further differ between sympatric and allopatric host-parasite combinations. Here, we test these hypotheses by in vitro exposure of head kidney leukocytes from three-spined sticklebacks (Gasterosteus aculeatus) to antigens from parasites with a broad fish host range (Diplostomum pseudospathaceum, Triaenophorus nodulosus), a specific fish parasite of cyprinids (Ligula intestinalis) and parasites highly specific only to a single fish species as second intermediate host (Schistocephalus pungitii, which does not infect G. aculeatus, and Schistocephalus solidus, infecting G. aculeatus). In vitro responses of stickleback leukocytes to S. solidus antigens from six European populations, with S. solidus prevalence from parasites and among specialists, from parasites that do not infect G. aculeatus to a G. aculeatus-infecting species. Generalist parasites seem to maintain their ability to infect different host species at the costs of relatively higher immunogenicity compared to specialist parasites. In a comparison of sympatric and allopatric combinations of stickleback leukocytes and antigens from S. solidus, magnitudes of in vitro responses were dependent on the prevalence of the parasite in the population of origin, rather than on sympatry. Antigens from Norwegian (prevalence 30-50%) and Spanish (40-66%) S. solidus induced generally higher in vitro responses compared to S. solidus from two German (<1%) populations. Likewise, leukocytes from

  17. Housekeeping genes for quantitative expression studies in the three-spined stickleback Gasterosteus aculeatus.

    Science.gov (United States)

    Hibbeler, Sascha; Scharsack, Joern P; Becker, Sven

    2008-01-29

    During the last years the quantification of immune response under immunological challenges, e.g. parasitation, has been a major focus of research. In this context, the expression of immune response genes in teleost fish has been surveyed for scientific and commercial purposes. Despite the fact that it was shown in teleostei and other taxa that the gene for beta-actin is not the most stably expressed housekeeping gene (HKG), depending on the tissue and experimental treatment, the gene has been used as a reference gene in such studies. In the three-spined stickleback, Gasterosteus aculeatus, other HKG than the one for beta-actin have not been established so far. To establish a reliable method for the measurement of immune gene expression in Gasterosteus aculeatus, sequences from the now available genome database and an EST library of the same species were used to select oligonucleotide primers for HKG, in order to perform quantitative reverse-transcription (RT) PCR. The expression stability of ten candidate reference genes was evaluated in three different tissues, and in five parasite treatment groups, using the three algorithms BestKeeper, geNorm and NormFinder. Our results showed that in most of the tissues and treatments HKG that could not be used so far due to unknown sequences, proved to be more stably expressed than the one for beta-actin. As they were the most stably expressed genes in all tissues examined, we suggest using the genes for the L13a ribosomal binding protein and ubiquitin as alternative or additional reference genes in expression analysis in Gasterosteus aculeatus.

  18. Housekeeping genes for quantitative expression studies in the three-spined stickleback Gasterosteus aculeatus

    Directory of Open Access Journals (Sweden)

    Becker Sven

    2008-01-01

    Full Text Available Abstract Background During the last years the quantification of immune response under immunological challenges, e.g. parasitation, has been a major focus of research. In this context, the expression of immune response genes in teleost fish has been surveyed for scientific and commercial purposes. Despite the fact that it was shown in teleostei and other taxa that the gene for beta-actin is not the most stably expressed housekeeping gene (HKG, depending on the tissue and experimental treatment, the gene has been used as a reference gene in such studies. In the three-spined stickleback, Gasterosteus aculeatus, other HKG than the one for beta-actin have not been established so far. Results To establish a reliable method for the measurement of immune gene expression in Gasterosteus aculeatus, sequences from the now available genome database and an EST library of the same species were used to select oligonucleotide primers for HKG, in order to perform quantitative reverse-transcription (RT PCR. The expression stability of ten candidate reference genes was evaluated in three different tissues, and in five parasite treatment groups, using the three algorithms BestKeeper, geNorm and NormFinder. Our results showed that in most of the tissues and treatments HKG that could not be used so far due to unknown sequences, proved to be more stably expressed than the one for beta-actin. Conclusion As they were the most stably expressed genes in all tissues examined, we suggest using the genes for the L13a ribosomal binding protein and ubiquitin as alternative or additional reference genes in expression analysis in Gasterosteus aculeatus.

  19. Predator-inspection behaviour in female three-spined sticklebacks Gasterosteus aculeatus is associated with status of gravidity.

    Science.gov (United States)

    Frommen, J G; Mehlis, M; Bakker, T C M

    2009-11-01

    Differences in predator-inspection behaviour between gravid and non-gravid female as well as between male and female three-spined sticklebacks Gasterosteus aculeatus were investigated. Gravid females confronted with a live rainbow trout Oncorhynchus mykiss showed bolder inspection behaviour than non-gravid ones. The behaviour of gravid females was comparable with that of males, maybe because both face a high risk of predation. The results indicate that antipredator behaviour in female G. aculeatus is not fixed but adjusted to their reproductive state.

  20. Biochemical peculiarity of in vitro morphogenesis under conservation strategy of Ruscus aculeatus L.

    Directory of Open Access Journals (Sweden)

    Cristian Banciu

    2009-12-01

    Full Text Available The present study is part of the actual concerns in biodiversity conservation of endangered angyosperm species from the Comana Natural Park. Ruscus aculeatus L. species is protected both at national and European level (trough Habitats Directive of EU and Bern Convention. The aspects of in vitro morphogenesis through all the stages from inoculation, multiplication to rooting and acclimatization have been studied. In order to long term conservation and multiplication or to exploit somaclonal variation induced by in vitro technique is required the identification of some biochemical or molecular markers for fast evaluation of regenerants. In this respect, genetic stability or variability of Ruscus aculeatus plants collected from three populations and regenerants obtained in vitro culture was estimated by electrophoretical methods. Therefore, zymograms of different enzymes as esterase, acid and alkaline phosphatase, glutamate-oxaloacetate transferase, malate dehydrogenase and peroxidase were analyzed. The expression of esterases, phosphatases, malate dehydrogenases displayed changes in correlation with growth condition, while the peroxidases pattern was more stabile in natural population as well as in vitro regenerated plantlet.

  1. The evolution of imprinting: chromosomal mapping of orthologues of mammalian imprinted domains in monotreme and marsupial mammals

    Directory of Open Access Journals (Sweden)

    Dunham Ian

    2007-09-01

    Full Text Available Abstract Background The evolution of genomic imprinting, the parental-origin specific expression of genes, is the subject of much debate. There are several theories to account for how the mechanism evolved including the hypothesis that it was driven by the evolution of X-inactivation, or that it arose from an ancestrally imprinted chromosome. Results Here we demonstrate that mammalian orthologues of imprinted genes are dispersed amongst autosomes in both monotreme and marsupial karyotypes. Conclusion These data, along with the similar distribution seen in birds, suggest that imprinted genes were not located on an ancestrally imprinted chromosome or associated with a sex chromosome. Our results suggest imprinting evolution was a stepwise, adaptive process, with each gene/cluster independently becoming imprinted as the need arose.

  2. Phylogeography and Conservation Genetics of the Ibero-Balearic Three-Spined Stickleback (Gasterosteus aculeatus)

    Science.gov (United States)

    Hermida, Miguel; Fernández, Carlos; Perea, Silvia; Doadrio, Ignacio; Amaro, Rafaela; San Miguel, Eduardo

    2017-01-01

    Genetic isolation and drift may imperil peripheral populations of wide-ranging species more than central ones. Therefore, information about species genetic variability and population structure is invaluable for conservation managers. The Iberian populations of three-spined stickleback lie at the southwestern periphery of the European distribution of Gasterosteus aculeatus. This teleost is a protected species in Portugal and Spain and local extinctions have been reported in both countries during the last decades. Our objectives were (i) to determine whether the Iberian populations of G. aculeatus are unique or composed of any of the major evolutionary lineages previously identified and (ii) to assess the evolutionary potential of these peripheral populations. We genotyped 478 individuals from 17 sites at 10 polymorphic microsatellite loci to evaluate the genetic variability and differentiation of the Ibero-Balearic populations. We also sequenced 1,165 bp of the mitochondrial genome in 331 of those individuals in order to complement the estimates of genetic diversity in the Ibero-Balearic region. We predicted the evolutionary potential of the different sites analysed based on the contribution of each of them to total allelic/mitochondrial diversity. An intraspecific phylogeny at European level was reconstructed using our data from the mitochondrial cytochrome b gene (755 bp) and published sequences. The so-called Transatlantic, European and Mediterranean mitochondrial lineages were found to be present in the Ibero-Balearic region. Their phylogeography suggests a history of multiple colonisations. The nuclear results show, however, a strong correlation between population structure and drainage system. The following basins should be prioritised by conservation policies in order to preserve those populations with the highest evolutionary potential: the Portuguese Vouga and Tagus as well as the Spanish Majorca and Limia. Maintenance of their connectivity, control of

  3. Hydrolysis of various thai agricultural biomasses using the crude enzyme from Aspergillus aculeatus iizuka FR60 isolated from soil

    Directory of Open Access Journals (Sweden)

    Atcha Boonmee

    2012-06-01

    Full Text Available In this study, forty-two fungi from soil were isolated and tested for their carboxymethyl cellulase (CMCase and xylanase activities. From all isolates, the fungal isolate FR60, which was identified as Aspergillus aculeatus Iizuka, showed high activities in both CMCase and xylanase with 517 mU/mg protein and 550 mU/mg protein, respectively. The crude enzyme from A. aculeatus Iizuka FR60 could hydrolyze several agricultural residues such as corncob, and sweet sorghum leaf and stalk at comparable rates with respect to the tested commercial enzymes and with a maximum rate in rice hull hydrolysis (29 μg sugar g-1 dry weight substrate mg-1 enzyme hr-1. The highest amount of glucose was obtained from corncob by using the crude enzyme from A. aculeatus Iizuka FR60 (10.1 g/100 g dry substrate. From overall enzymatic treatment results, the lowest sugar yield was from rice hulls treatment (1.6 g/100 g dry weight and the highest amount of reducing sugar was obtained from rice straw treatment (15.3 g/100 g dry weight. Among tested agricultural wastes, rice hull could not be effectively hydrolyzed by enzymes, whereas sugarcane leaf and stalk, and peanut shell could be effectively hydrolyzed (30-31% total sugar comparing with total sugar yield from acid treatment.

  4. Nutritional benefits of filial cannibalism in three-spined sticklebacks (Gasterosteus aculeatus).

    Science.gov (United States)

    Mehlis, Marion; Bakker, Theo C M; Frommen, Joachim G

    2009-03-01

    Although filial cannibalism (eating one's own offspring) occurs in numerous species, including several teleost fishes, its adaptive value is still not well understood. One often-discussed explanation is that individuals enhance their mass and body condition by consuming part of their eggs. However, evidence for this assumption is scarce thus far. In this study, male three-spined sticklebacks (Gasterosteus aculeatus), a species with paternal care, were allowed to care for a batch of eggs or for an empty nest under food-deprived conditions. All brood-caring males cannibalised at least part of their eggs and thus preserved their initial mass and body condition. Furthermore, mass as well as body condition was significant positively correlated with the number of cannibalised eggs. In contrast, empty-nest males that had no possibility to cannibalise eggs significantly lost mass and body condition. This is, to our knowledge, the first experimentally documented evidence that mass as well as body condition were preserved by filial cannibalism.

  5. High degree of genetic differentiation in marine three-spined sticklebacks (Gasterosteus aculeatus).

    Science.gov (United States)

    Defaveri, Jacquelin; Shikano, Takahito; Shimada, Yukinori; Merilä, Juha

    2013-09-01

    Populations of widespread marine organisms are typically characterized by a low degree of genetic differentiation in neutral genetic markers, but much less is known about differentiation in genes whose functional roles are associated with specific selection regimes. To uncover possible adaptive population divergence and heterogeneous genomic differentiation in marine three-spined sticklebacks (Gasterosteus aculeatus), we used a candidate gene-based genome-scan approach to analyse variability in 138 microsatellite loci located within/close to (genetic differentiation in markers classified as neutral or under balancing selection-as determined with several outlier detection methods-was low (F(ST) = 0.033 or 0.011, respectively), whereas average FST for directionally selected markers was significantly higher (F(ST) = 0.097). Clustering analyses provided support for genomic and geographic heterogeneity in selection: six genetic clusters were identified based on allele frequency differences in the directionally selected loci, whereas four were identified with the neutral loci. Allelic variation in several loci exhibited significant associations with environmental variables, supporting the conjecture that temperature and salinity, but not optic conditions, are important drivers of adaptive divergence among populations. In general, these results suggest that in spite of the high degree of physical connectivity and gene flow as inferred from neutral marker genes, marine stickleback populations are strongly genetically structured in loci associated with functionally relevant genes.

  6. Individual variation in habituation: behaviour over time toward different stimuli in threespine sticklebacks (Gasterosteus aculeatus)

    Science.gov (United States)

    Bell, Alison M.; Peeke, Harman V.S.

    2014-01-01

    Habituation, or the relatively permanent waning of a response as a result of repeated stimulation, is a form of behavioural plasticity that allows animals to filter out irrelevant stimuli and to focus selectively on important stimuli. Individuals that fail to habituate might be at a disadvantage if they continue to respond to irrelevant stimuli; therefore, habituation can have adaptive significance. In this study we compared rates of behaviour over time toward three different ecologically-relevant stimuli (food, a male intruder and a gravid female) in threespine sticklebacks (Gasterosteus aculeatus). We detected evidence for habituation to the stimuli, and males in this study were especially aggressive toward both male and female conspecifics. Although there were some clear temporal patterns that could be detected by looking at average behaviour, not all individuals behaved in the same ‘average’ way. We detected substantial inter-individual variation in behaviour toward all three stimuli, inter-individual variation in rates of habituation to both male and female conspecifics, but no evidence for correlations between behaviours across stimuli (behavioural syndromes). These results suggest that individual animals vary in rates of habituation, and prompt hypotheses about the causes and consequences of variation in rates of habituation. PMID:25678715

  7. Divergent Macroparasite Infections in Parapatric Swiss Lake-Stream Pairs of Threespine Stickleback (Gasterosteus aculeatus.

    Directory of Open Access Journals (Sweden)

    Anssi Karvonen

    Full Text Available Spatial heterogeneity in diversity and intensity of parasitism is a typical feature of most host-parasite interactions, but understanding of the evolutionary implications of such variation is limited. One possible outcome of infection heterogeneities is parasite-mediated divergent selection between host populations, ecotypes or species which may facilitate the process of ecological speciation. However, very few studies have described infections in population-pairs along the speciation continuum from low to moderate or high degree of genetic differentiation that would address the possibility of parasite-mediated divergent selection in the early stages of the speciation process. Here we provide an example of divergent parasitism in freshwater fish ecotypes by examining macroparasite infections in threespine stickleback (Gasterosteus aculeatus of four Swiss lake systems each harbouring parapatric lake-stream ecotype pairs. We demonstrate significant differences in infections within and between the pairs that are driven particularly by the parasite taxa transmitted to fish from benthic invertebrates. The magnitude of the differences tended to correlate positively with the extent of neutral genetic differentiation between the parapatric lake and stream populations of stickleback, whereas no such correlation was found among allopatric populations from similar or contrasting habitats. This suggests that genetic differentiation is unrelated to the magnitude of parasite infection contrasts when gene flow is constrained by geographical barriers while in the absence of physical barriers, genetic differentiation and the magnitude of differences in infections tend to be positively correlated.

  8. Investigation of a 6-MSA Synthase Gene Cluster in Aspergillus aculeatus Reveals 6-MSA-derived Aculinic Acid, Aculins A-B and Epi-Aculin A.

    Science.gov (United States)

    Petersen, Lene M; Holm, Dorte K; Gotfredsen, Charlotte H; Mortensen, Uffe H; Larsen, Thomas O

    2015-10-12

    Aspergillus aculeatus, a filamentous fungus belonging to the Aspergillus clade Nigri, is an industrial workhorse in enzyme production. Recently we reported a number of secondary metabolites from this fungus; however, its genetic potential for the production of secondary metabolites is vast. In this study we identified a 6-methylsalicylic acid (6-MSA) synthase from A. aculeatus, and verified its functionality by episomal expression in A. aculeatus and heterologous expression in A. nidulans. Feeding studies with fully (13) C-labeled 6-MSA revealed that 6-MSA is incorporated into aculinic acid, which further incorporates into three compounds that we name aculins A and B, and epi-aculin A, described here for the first time. Based on NMR data and bioinformatic studies we propose the structures of the compounds as well as a biosynthetic pathway leading to formation of aculins from 6-MSA.

  9. The effect of methyl jasmonate on triterpene and sterol metabolisms of Centella asiatica, Ruscus aculeatus and Galphimia glauca cultured plants.

    Science.gov (United States)

    Mangas, Susana; Bonfill, Mercè; Osuna, Lidia; Moyano, Elisabeth; Tortoriello, Jaime; Cusido, Rosa M; Piñol, M Teresa; Palazón, Javier

    2006-09-01

    Considering that exogenously applied methyl jasmonate can enhance secondary metabolite production in a variety of plant species and that 2,3-oxidosqualene is a common precursor of triterpenes and sterols in plants, we have studied Centella asiatica and Galphimia glauca (both synthesizing triterpenoid secondary compounds) and Ruscus aculeatus (which synthesizes steroidal secondary compounds) for their growth rate and content of free sterols and respective secondary compounds, after culturing with or without 100 microM methyl jasmonate. Our results show that elicited plantlets of G. glauca and to a higher degree C. asiatica (up to 152-times more) increased their content of triterpenoids directly synthesized from 2,3-oxidosqualene (ursane saponins and nor-seco-friedelane galphimines, respectively) at the same time as growth decreased. In contrast, the free sterol content of C. asiatica decreased notably, and remained practically unaltered in G. glauca. However, in the case of R. aculeatus, which synthesizes steroidal saponins (mainly spirostane type) indirectly from 2,3-oxidosqualene after the latter is converted to the plant phytosterol-precursor cycloartenol, while the growth rate and free sterol content clearly decreased, the spirostane saponine content was virtually unchanged (aerial part) or somewhat lower (roots) in presence of the same elicitor concentration. Our results suggest that while methyl jasmonate may be used as an inducer of enzymes involved in the triterpenoid synthesis downstream from 2,3-oxidosqualene in both C. asiatica and G. glauca plantlets, in those of C. asiatica and R. aculeatus it inhibited the enzymes involved in sterol synthesis downstream from cycloartenol.

  10. Infestación de Megastigmus aculeatus (Hymenoptera: Chalcidoidea en las semillas de rosas exóticas invasoras de comunidades naturales de la Patagonia andina de Argentina Megastigmus aculeatus infestation on seeds of exotic roses invading wild communities of Andean Patagonia from Argentina

    Directory of Open Access Journals (Sweden)

    KAREN D LEDIUK

    2012-03-01

    Full Text Available Megastigmus aculeatus Swederus (Hymenoptera: Chalcidoidea infesta las semillas de especies de Rosa tanto en las áreas de origen como en las de invasión. La larva de la avispa se desarrolla consumiendo la totalidad de la semilla. Se analizó la infestación de M. aculeatus en diferentes poblaciones de Rosa rubiginosa L. y Rosa canina L. y en plantas aisladas de Rosa multiflora Thunb. en áreas naturales del Noroeste de la Patagonia, Argentina. En R. rubiginosa, la especie más abundante, estudiamos la prevalencia y éxito de infestación por la avispa y el posible efecto sobre el tamaño del fruto. En este trabajo se presentan los primeros registros de R. rubiginosa y R. canina como especies hospedadoras de M. aculeatus en Argentina y se verifica su ausencia en las semillas de R. multiflora. En R. canina, el porcentaje de frutos infestados por M. aculeatus fue bajo (0-1 % por sitio, no siendo probablemente un factor condicionante de la reducida distribución de la planta. En R. rubiginosa, ese porcentaje fue alto (31-75 % de frutos infestados por sitio, pero solo el 2-8 % de los aquenios estaban infestados. Considerando los sitios analizados, la distribución a nivel regional de la infestación por M. aculeatus en las especies de rosas estudiadas es reducida. El tamaño del fruto no es afectado por la infestación del insecto. Los resultados de este trabajo muestran un bajo impacto actual de M. aculeatus en el control natural de la invasión de las rosas en la región andina de Argentina. Sin embargo, dado que las poblaciones de M. aculeatus podrían ser afectadas por la temperatura, un cambio en esta variable podría incrementar la prevalencia de infestación de las semillas de estos arbustos a mediano y largo plazo.Megastigmus aculeatus Swederus (Hymenoptera: Chalcidoidea infest Rosa species seeds both at the origin and invasion areas. The wasp larvae develop by consuming the entire seed. The M. aculeatus infestation was analyzed at different

  11. Optimization of process parameters for enhanced production of Jamun juice using Pectinase (Aspergillus aculeatus) enzyme and its characterization

    OpenAIRE

    Ghosh, Payel; Pradhan, Rama Chandra; Mishra, Sabyasachi

    2016-01-01

    Jamun fruit comprises of seed and thick pulp. The pectin–protein bond of the thick pulp creates difficulty in making juice. Clear Jamun juice is not available in the market, so there is a need for extraction of juice with maximum yield. The goal of this research is to obtain high yield of clarified juice with the help of Pectinase (Aspergillus aculeatus) enzyme. The study was conducted at different enzyme concentration (0.01–0.1%), time duration (40–120 min), and temperature (30–50 °C). Vario...

  12. Development of a bioenergetics model for the threespine stickleback Gasterosteus aculeatus

    Science.gov (United States)

    Hovel, Rachel A.; Beauchamp, David A.; Hansen, Adam G.; Sorel, Mark H.

    2016-01-01

    The Threespine Stickleback Gasterosteus aculeatus is widely distributed across northern hemisphere ecosystems, has ecological influence as an abundant planktivore, and is commonly used as a model organism, but the species lacks a comprehensive model to describe bioenergetic performance in response to varying environmental or ecological conditions. This study parameterized a bioenergetics model for the Threespine Stickleback using laboratory measurements to determine mass- and temperature-dependent functions for maximum consumption and routine respiration costs. Maximum consumption experiments were conducted across a range of temperatures from 7.5°C to 23.0°C and a range of fish weights from 0.5 to 4.5 g. Respiration experiments were conducted across a range of temperatures from 8°C to 28°C. Model sensitivity was consistent with other comparable models in that the mass-dependent parameters for maximum consumption were the most sensitive. Growth estimates based on the Threespine Stickleback bioenergetics model suggested that 22°C is the optimal temperature for growth when food is not limiting. The bioenergetics model performed well when used to predict independent, paired measures of consumption and growth observed from a separate wild population of Threespine Sticklebacks. Predicted values for consumption and growth (expressed as percent body weight per day) only deviated from observed values by 2.0%. Our model should provide insight into the physiological performance of this species across a range of environmental conditions and be useful for quantifying the trophic impact of this species in food webs containing other ecologically or economically important species.

  13. Mechanisms underlying parallel reductions in aerobic capacity in non-migratory threespine stickleback (Gasterosteus aculeatus) populations.

    Science.gov (United States)

    Dalziel, Anne C; Ou, Michelle; Schulte, Patricia M

    2012-03-01

    Non-migratory, stream-resident populations of threespine stickleback, Gasterosteus aculeatus, have a lower maximum oxygen consumption ((O(2),max)) than ancestral migratory marine populations. Here, we examined laboratory-bred stream-resident and marine crosses from two locations (West and Bonsall Creeks) to determine which steps in the oxygen transport and utilization cascade evolved in conjunction with, and thus have the potential to contribute to, these differences in (O(2),max). We found that West Creek stream-resident fish have larger muscle fibres (not measured in Bonsall fish), Bonsall Creek stream-resident fish have smaller ventricles, and both stream-resident populations have evolved smaller pectoral adductor and abductor muscles. However, many steps of the oxygen cascade did not evolve in stream-resident populations (gill surface area, hematocrit, mean cellular hemoglobin content and the activities of mitochondrial enzymes per gram ventricle and pectoral muscle), arguing against symmorphosis. We also studied F1 hybrids to determine which traits in the oxygen cascade have a genetic architecture similar to that of (O(2),max). In West Creek, (O(2),max), abductor and adductor size all showed dominance of marine alleles, whereas in Bonsall Creek, (O(2),max) and ventricle mass showed dominance of stream-resident alleles. We also found genetically based differences among marine populations in hematocrit, ventricle mass, pectoral muscle mass and pectoral muscle pyruvate kinase activity. Overall, reductions in pectoral muscle mass evolved in conjunction with reductions in (O(2),max) in both stream-resident populations, but the specific steps in the oxygen cascade that have a genetic basis similar to that of (O(2),max), and are thus predicted to have the largest impact on (O(2),max), differ among populations.

  14. Hepatic transcriptomic and metabolomic responses in the Stickleback (Gasterosteus aculeatus) exposed to ethinyl-estradiol

    Energy Technology Data Exchange (ETDEWEB)

    Katsiadaki, Ioanna, E-mail: ioanna.katsiadaki@cefas.co.uk [Centre for Environment, Fisheries and Aquaculture Science, Cefas Weymouth Laboratory, Weymouth, Dorset DT4 8UB (United Kingdom); Williams, Tim D. [School of Biosciences, University of Birmingham, Birmingham, B15 2TT (United Kingdom); Ball, Jonathan S. [School of Biosciences, University of Exeter, Exeter, Devon, EX4 4QJ (United Kingdom); Bean, Tim P.; Sanders, Matthew B. [Centre for Environment, Fisheries and Aquaculture Science, Cefas Weymouth Laboratory, Weymouth, Dorset DT4 8UB (United Kingdom); Wu Huifeng [School of Biosciences, University of Birmingham, Birmingham, B15 2TT (United Kingdom); Santos, Eduarda M. [School of Biosciences, University of Exeter, Exeter, Devon, EX4 4QJ (United Kingdom); Brown, Margaret M.; Baker, Paul [School of Biological and Biomedical Sciences, Glasgow Caledonian University, Glasgow, G4 0BA (United Kingdom); Ortega, Fernando; Falciani, Francesco [School of Biosciences, University of Birmingham, Birmingham, B15 2TT (United Kingdom); Craft, John A. [School of Biological and Biomedical Sciences, Glasgow Caledonian University, Glasgow, G4 0BA (United Kingdom); Tyler, Charles R. [School of Biosciences, University of Exeter, Exeter, Devon, EX4 4QJ (United Kingdom); Viant, Mark R.; Chipman, James K. [School of Biosciences, The University of Birmingham, Birmingham, B15 2TT (United Kingdom)

    2010-05-05

    An established three-spined stickleback (Gasterosteus aculeatus) cDNA array was expanded to 14,496 probes with the addition of hepatic clones derived from subtractive and normalized libraries from control males and males exposed to model toxicants. Microarrays and one-dimensional {sup 1}H nuclear magnetic resonance (NMR) spectroscopy, together with individual protein and gene biomarkers were employed to investigate the hepatic responses of the stickleback to ethinyl-estradiol (EE{sub 2}) exposure. Male fish were exposed via the water to EE{sub 2}, including environmentally relevant concentrations (0.1-100 ng/l) for 4 days, and hepatic transcript and metabolite profiles, kidney spiggin protein and serum vitellogenin concentrations were determined in comparison to controls. EE{sub 2} exposure did not significantly affect spiggin concentration but significantly induced serum vitellogenin protein at the threshold concentration of 32 ng/l. {sup 1}H NMR coupled with robust univariate testing revealed only limited changes, but these did support the predicted modulation of the amino acid profile by transcriptomics. Transcriptional induction was found for hepatic vitellogenins and choriogenins as expected, together with a range of other EE{sub 2}-responsive genes. Choriogenins showed the more sensitive responses with statistically significant induction at 10 ng/l. Real-time polymerase chain reaction (PCR) confirmed transcriptional induction of these genes. Phosvitinless vitellogenin C transcripts were highly expressed and represent a major form of the egg yolk precursors, and this is in contrast to other fish species where it is a minor component of vitellogenic transcripts. Differences in inducibility between the vitellogenins and choriogenins appear to be in accordance with the sequential formation of chorion and yolk during oogenesis in fish.

  15. Induction of diploid gynogenesis in an evolutionary model organism, the three-spined stickleback (Gasterosteus aculeatus

    Directory of Open Access Journals (Sweden)

    Scharsack Jörn P

    2011-09-01

    Full Text Available Abstract Background Rapid advances in genomics have provided nearly complete genome sequences for many different species. However, no matter how the sequencing technology has improved, natural genetic polymorphism complicates the production of high quality reference genomes. To address this problem, researchers have tried using artificial modes of genome manipulation such as gynogenesis for fast production of inbred lines. Results Here, we present the first successful induction of diploid gynogenesis in an evolutionary model system, the three-spined sticklebacks (Gasterosteus aculeatus, using a combination of UV-irradiation of the sperm and heat shock (HS of the resulting embryo to inhibit the second meiotic division. Optimal UV irradiation of the sperm was established by exposing stickleback sperm to a UV- light source at various times. Heat shock parameters like temperature, duration, and time of initiation were tested by subjecting eggs fertilized with UV inactivated sperm 5, 10, 15, 20, 25, or 30 minutes post fertilization (mpf to 30°C, 34°C, or 38°C for 2, 4, 6 or 8 minutes. Gynogen yield was highest when stickleback eggs were activated with 2 minutes UV-irradiated sperm and received HS 5 mpf at 34°C for 4 minutes. Conclusions Diploid gynogenesis has been successfully performed in three-spined stickleback. This has been confirmed by microsatellite DNA analysis which revealed exclusively maternal inheritance in all gynogenetic fry tested. Ploidy verification by flow cytometry showed that gynogenetic embryos/larvae exhibiting abnormalities were haploids and those that developed normally were diploids, i.e., double haploids that can be raised until adult size.

  16. Optimization of process parameters for enhanced production of Jamun juice using Pectinase (Aspergillus aculeatus) enzyme and its characterization.

    Science.gov (United States)

    Ghosh, Payel; Pradhan, Rama Chandra; Mishra, Sabyasachi

    2016-12-01

    Jamun fruit comprises of seed and thick pulp. The pectin-protein bond of the thick pulp creates difficulty in making juice. Clear Jamun juice is not available in the market, so there is a need for extraction of juice with maximum yield. The goal of this research is to obtain high yield of clarified juice with the help of Pectinase (Aspergillus aculeatus) enzyme. The study was conducted at different enzyme concentration (0.01-0.1%), time duration (40-120 min), and temperature (30-50 °C). Various physical and chemical parameters, such as yield, turbidity, viscosity, clarity, colour, polyphenol, protein, TSS, and total solid, were measured as dependent variables. Process optimization has been done using Box-Behnken design. Optimization has been done for maximum yield percentage, L* value, a* value, protein, and polyphenol content, and minimum values for turbidity, viscosity, clarity, b* value, TSS, and total solid content. The suggested parameters for extraction of juice were at 0.05% enzyme concentration at 44 °C for 80 min. In a large-scale production, extraction of juice by Pectinase (Aspergillus aculeatus) has a significance importance due to its high yield as well as nutritional values.

  17. Investigation of a 6-MSA Synthase Gene Cluster in Aspergillus aculeatus Reveals 6-MSA-derived Aculinic Acid, Aculins A-B and Epi-Aculin A

    DEFF Research Database (Denmark)

    Petersen, Lene Maj; Holm, Dorte Koefoed; Gotfredsen, Charlotte Held

    2015-01-01

    Aspergillus aculeatus, a filamentous fungus belonging to the Aspergillus clade Nigri, is an industrial workhorse in enzyme production. Recently we reported a number of secondary metabolites from this fungus; however, its genetic potential for the production of secondary metabolites is vast. In th...

  18. A new intertidal arthrotardigrade, Prostygarctus aculeatus gen. nov., sp. nov. (Tardigrada: Heterotardigrada from the North of Portugal (Atlantic ocean

    Directory of Open Access Journals (Sweden)

    Marcos Rubal

    2013-03-01

    Full Text Available A new arthrotardigrade, Prostygarctus aculeatus gen. nov., sp. nov. is described from intertidal meiobenthos samples collected at Ofir beach, Esposende, North of Portugal. The new species, an armoured arthrotardigrade of the family Stygarctidae, is easily distinguished from all the other stygarctids by an unusual caudal apparatus, which consists of a very long medial spine with two lateral furca-like processes. It is also characterised by the presence of backwardly directed dorsal spines and a pair of ventral spines. Furthermore, it has four digits on each leg, ending in simple claws. The morphological peculiarities exhibited by the new species justify the establishment of a new genus and will provide useful insights to help develop our understanding of the phylogenetic relationships of armoured arthrotardigrades.

  19. Effect of Australian tea tree oil on Gyrodactylus spp. infection of the three-spined stickleback Gasterosteus aculeatus.

    Science.gov (United States)

    Steverding, Dietmar; Morgan, Edward; Tkaczynski, Patrick; Walder, Foster; Tinsley, Richard

    2005-08-09

    Gyrodactylus spp. infections of commercially farmed fishes are responsible for significant economic losses. Existing treatments have proved uneconomic, stressful to the fishes, and ecologically damaging. Essential oils are naturally occurring compounds that exhibit a wide range of anti-microbial and anti-fungal activities. This study explored the possibility of using Australian tea tree (Melaleuca alternifolia) oil (TTO) to treat Gyrodactylus spp. infection on the three-spined stickleback Gasterosteus aculeatus. In the presence of 0.01 % Tween 80 as an emulsifier, TTO treatments at concentrations between 3 and 30 ppmv (parts per million by volume) lowered the prevalence and significantly reduced the parasite burden of sticklebacks naturally infected with Gyrodactylus spp. In addition, Tween 80 alone exhibited parasiticidal activity against Gyrodactylus spp. These findings show the potential of TTO in combination with Tween 80 as an effective treatment of Gyrodactylus spp. infection of fishes.

  20. The role of calcium and predation on plate morph evolution in the three-spined stickleback (Gasterosteus aculeatus).

    Science.gov (United States)

    Smith, Carl; Spence, Rowena; Barber, Iain; Przybylski, Mirosław; Wootton, Robert J

    2014-09-01

    While the genetic basis to plate morph evolution of the three-spined stickleback (Gasterosteus aculeatus) is well described, the environmental variables that select for different plate and spine morphs are incompletely understood. Using replicate populations of three-spined sticklebacks on North Uist, Scotland, we previously investigated the role of predation pressure and calcium limitation on the adaptive evolution of stickleback morphology and behavior. While dissolved calcium proved a significant predictor of plate and spine morph, predator abundance did not. Ecol. Evol., xxx, 2014 and xxx performed a comparable analysis to our own to address the same question. They failed to detect a significant effect of dissolved calcium on morphological evolution, but did establish a significant effect of predation; albeit in the opposite direction to their prediction.

  1. Brain and behaviour of living and extinct echidnas.

    Science.gov (United States)

    Ashwell, Ken W S; Hardman, Craig D; Musser, Anne M

    2014-10-01

    The Tachyglossidae (long- and short-beaked echidnas) are a family of monotremes, confined to Australia and New Guinea, that exhibit striking trigeminal, olfactory and cortical specialisations. Several species of long-beaked echidna (Zaglossus robusta, Zaglossus hacketti, Megalibgwilia ramsayi) were part of the large-bodied (10 kg or more) fauna of Pleistocene Australasia, but only the diminutive (2-7 kg) Tachyglossus aculeatus is widespread today on the Australian mainland. We used high-resolution CT scanning and other osteological techniques to determine whether the remarkable neurological specialisations of modern echidnas were also present in Pleistocene forms or have undergone modification as the Australian climate changed in the transition from the Pleistocene to the Holocene. All the living and extinct echidnas studied have a similar pattern of cortical gyrification that suggests comparable functional topography to the modern short-beaked form. Osteological features related to olfactory, trigeminal, auditory and vestibular specialisation (e.g., foramina and cribriform plate area, osseous labyrinth topography) are also similar in living and extinct species. Our findings indicate that despite differences in diet, habitat and body size, the suite of neurological specialisations in the Tachyglossidae has been remarkably constant: encephalisation, sensory anatomy and specialisation (olfactory, trigeminal, auditory and vestibular), hypoglossal nerve size and cortical topography have all been stable neurological features of the group for at least 300,000 years. Crown Copyright © 2014. Published by Elsevier GmbH. All rights reserved.

  2. THE CONSTRUCTION OF X CHROMOSOME LIBRARY OF SPINY EEL (MASTACEMBELUS ACULEATUS)%刺鳅X染色体DNA文库的构建

    Institute of Scientific and Technical Information of China (English)

    陈戟; 赵刚; 臧亚婷; 余其兴; 刘江东

    2009-01-01

    The spiny eel (Mastacembelus aculeatus) is a species of the genus Mastacembelus (Osteichthyes, Perciformes), which mainly live in the fresh water of the south of China. The fish is particularly attractive for cytogeneti-cal study owing to possessing well differentiated X and Y sex chromosomes.In the present study, the X chromosomes of M. aculeatus were microdissected from the metaphases of chromosomes of the female. Then, the fragments of X chromosomes were put into a micro tube and amplified using Degenerated Oligonucleotide-Primed PCR (DOP-PCR). Thereafter, the product of PCR was connected to T vector and the plasmids were electric transformed into E. coli. As a result, the library of X chromosome of M. aculeatus was constructed. The sum of the lengths of the inserted fragments is some 1.08 × 108bp, with an average length of 500bp. It is believed that the library covered more than 98% sequences of the whole X chromosome theoretically.To check the credibility of the library, fluorescence in situ hybridization (FISH) was applied. The fragments of the library were labeled with biotin by PCR. Then the probes were hybridized to the chromosome metaphases of both sex of M. aculeatus in the absence or the presence of competitor DNA. Strong signals were detected on the entire sex chromosomes as well as signals dispersed on all autosomes with the condition of FISH in the absence of competitor DNA. Whereas competitor DNA was added, the signals disappeared except those showed on heteroehromatic regions of X and Y chromosomes. Hence, we assorted the repetitive sequences in the X chromosome of M. aculeatus into three types. It was interpreted that the signals of FISH in the presence of competitor DNA showed the distribution of type Ⅱ repetitive sequences on the sex chromosomes of M. aculeatus.%刺鳅(Mastacembelus aculeatus)是具有明显X和Y异形性染色体分化的淡水鱼.本实验室通过显微切割(Mi-crodissection)和兼并引物PCR(DOP-PCR)方法,从雌性刺

  3. Distinct development of the trigeminal sensory nuclei in platypus and echidna.

    Science.gov (United States)

    Ashwell, Ken W S; Hardman, Craig D

    2012-01-01

    Both lineages of the modern monotremes have been reported to be capable of electroreception using the trigeminal pathways and it has been argued that electroreception arose in an aquatic platypus-like ancestor of both modern monotreme groups. On the other hand, the trigeminal sensory nuclear complex of the platypus is highly modified for processing tactile and electrosensory information from the bill, whereas the trigeminal sensory nuclear complex of the short-beaked echidna (Tachyglossus aculeatus) is not particularly specialized. If the common ancestor for both platypus and echidna were an electroreceptively and trigeminally specialized aquatic feeder, one would expect the early stages of development of the trigeminal sensory nuclei in both species to show evidence of structural specialization from the outset. To determine whether this is the case, we examined the development of the trigeminal sensory nuclei in the platypus and short-beaked echidna using the Hill and Hubrecht embryological collections. We found that the highly specialized features of the platypus trigeminal sensory nuclei (i.e. the large size of the principal nucleus and oral part of the spinal trigeminal nuclear complex, and the presence of a dorsolateral parvicellular segment in the principal nucleus) appear around the time of hatching in the platypus, but are never seen at any stage in the echidna. Our findings support the proposition that the modern echidna and platypus are derived from a common ancestor with only minimal trigeminal specialization and that the peculiar anatomy of the trigeminal sensory nuclei in the modern platypus emerged in the ornithorhynchids after divergence from the tachyglossids. Copyright © 2012 S. Karger AG, Basel.

  4. Rapid molecular sexing of three-spined sticklebacks, Gasterosteus aculeatus L., based on large Y-chromosomal insertions.

    Science.gov (United States)

    Bakker, Theo C M; Giger, Thomas; Frommen, Joachim G; Largiadèr, Carlo R

    2017-08-01

    There is a need for rapid and reliable molecular sexing of three-spined sticklebacks, Gasterosteus aculeatus, the supermodel species for evolutionary biology. A DNA region at the 5' end of the sex-linked microsatellite Gac4202 was sequenced for the X chromosome of six females and the Y chromosome of five males from three populations. The Y chromosome contained two large insertions, which did not recombine with the phenotype of sex in a cross of 322 individuals. Genetic variation (SNPs and indels) within the insertions was smaller than on flanking DNA sequences. Three molecular PCR-based sex tests were developed, in which the first, the second or both insertions were covered. In five European populations (from DE, CH, NL, GB) of three-spined sticklebacks, tests with both insertions combined showed two clearly separated bands on agarose minigels in males and one band in females. The tests with the separate insertions gave similar results. Thus, the new molecular sexing method gave rapid and reliable results for sexing three-spined sticklebacks and is an improvement and/or alternative to existing methods.

  5. Smells like sib spirit: kin recognition in three-spined sticklebacks (Gasterosteus aculeatus) is mediated by olfactory cues.

    Science.gov (United States)

    Mehlis, Marion; Bakker, Theo C M; Frommen, Joachim G

    2008-10-01

    The ability to recognise kin has been demonstrated in several animal species. However, the mechanisms of kin recognition often remain unknown. The most frequently discussed sensory modalities to recognise kin are visual, olfactory and acoustical cues. Three-spined sticklebacks (Gasterosteus aculeatus) are able to differentiate between kin and non-kin when presented visual and olfactory cues combined. To elucidate, which cues they use to recognise kin female sticklebacks were given the choice between two identical computer animations of courting stickleback males. Next to one animation, water conditioned by a brother was added, while near the other, water from an unrelated male was added. In half of the experiments, the brother was familiar while in the other half he was unfamiliar to the female. Both scenarios were carried out with both outbred and inbred fish. The results showed that the females adjusted their choice behaviour according to relatedness. Furthermore, they were able to recognise both familiar as well as unfamiliar brothers. Inbreeding did not affect this ability. Hence, three-spined sticklebacks are able to recognise their relatives using olfactory cues alone. The cognitive mechanisms underlying this ability were independent from familiarity and not impaired by inbreeding.

  6. Environmental factors influencing survival of threespine stickleback (Gasterosteus aculeatus) in a multipurpose constructed treatment wetland in southern California.

    Science.gov (United States)

    Walton, William E; Wirth, Margaret C; Workman, Parker D

    2007-06-01

    Survival of the threespine stickleback, Gasterosteus aculeatus, differed among marshes in a demonstration 9.9-ha multipurpose constructed treatment wetland designed to improve the quality of secondary-treated municipal wastewater in southern California. At a mean loading rate of 3.3 kg NH4-N ha(-1) d(-1) (6 kg total N ha(-1) d(-1)), the suitability of the wetland to support a population of sticklebacks was estimated to be low. The development of potentially toxic levels of un-ionized ammonia, particularly during periods when pH increased concomitantly with oxygen generation by phytoplankton biomass > 300 mg chlorophyll a liter(-1), and disinfection by-products were associated with lowered survivorship of sentinel fish. Moreover, the high oxygen demand from nitrification of NH4-N created daily periods of low dissolved oxygen concentration (6-16 h at dissolved oxygen concentration in open water zones of the seven marshes during a part of each day and persistent anaerobic conditions in the emergent vegetation rendered the majority of the wetland's substrate surface unavailable for successful reproduction by sticklebacks. The potential sites for Gasterosteus to replace mosquitofish, Gambusia affinis and G. holbrooki, as a biological control agent against mosquitoes are probably limited to comparatively cool-water habitats with high water quality, such as riverine wetlands.

  7. Males do not see only red: UV wavelengths and male territorial aggression in the three-spined stickleback ( Gasterosteus aculeatus)

    Science.gov (United States)

    Rick, Ingolf P.; Bakker, Theo C. M.

    2008-07-01

    Animal colour signals serve important functions in intraspecific interactions, including species recognition, mate choice and agonistic behaviour. An increasing interest concerns ultraviolet (UV) wavelengths, for instance studies on the effect of UV in mating decisions. More recently, some studies also established that UV signals affect intrasexual interactions. We studied the role of UV during aggressive encounters between male three-spined sticklebacks ( Gasterosteus aculeatus), a species in which UV has an effect on female and male mate choice and shoaling behaviour. To that aim, we compared the aggressive response of a territorial male to male intruders, either seen in UV-including (UV+) or UV-lacking (UV-) conditions. Our prediction was that, if UV wavelengths are used in male-male competition, a territorial male should show less competitive behaviour towards an intruder representing a lower threat, i.e. the one presented without UV light. Male sticklebacks showed significantly lower levels of aggression towards male opponents lacking an UV component to their coloration than male opponents possessing this colour component. Discrimination was not influenced by a difference in brightness between the UV+ and UV- stimuli. Finally, we present some reflectance-spectrophotometrical data of two skin regions (cheek and abdomen) of the experimental males and analysed relationships between colorimetric variables, body variables and behaviour. Our study emphasises that UV visual cues are of importance in different communicational tasks in the three-spined stickleback.

  8. Male-male and male-female aggression may influence mating associations in wild octopuses (Abdopus aculeatus).

    Science.gov (United States)

    Huffard, Christine L; Caldwell, Roy L; Boneka, Farnis

    2010-02-01

    Abdopus aculeatus engages in frequent aggression and copulation, exhibits male mate-choice, and employs multiple mating tactics. Here we draw upon established hypotheses to compare male-male aggression (MMA) and male-female aggression (MFA), as they relate to their mating behavior in the wild. When contesting for females, males appear to balance mate preference (resource value) with perceived chances of winning contests (resource holding potential). Although males spent more time mating with and contesting for large "Adjacent Guarded" females (those occupying a den within arm's reach of a large "Adjacent Guarding" male), they exhibited higher rates of aggression over nonadjacent "Temporarily Guarded" females that may be more accessible. The major determinant of male-male aggressive success was size, and this factor may dictate the expression of conditional mating tactics in males. "Adjacent Guarding" males were the largest and most aggressively successful males, earning the most time copulating with females. They are considered to have the highest resource holding potential (RHP) in MMA. By contrast, in MFA, some larger individuals fled from smaller individuals, indicating that RHP appears to be a function of both size and sex in intersexual aggression. This result suggests variation in aggressiveness, or potential for severe injury-even sexual cannibalism during MFA. Male-female aggression may also be influenced by the sexual nonreceptivity of some individuals, or attempts by both sexes to increase foraging behavior by delaying mate-guarding activity.

  9. Repeatability of decision-making behaviour in male threespine stickleback Gasterosteus aculeatus: Effects of dummy vs.Live stimuli

    Institute of Scientific and Technical Information of China (English)

    Teresa L. DZIEWECZYNSKI; Lindsay M. FORRETTE

    2011-01-01

    Individuals select from a number of behaviours when responding to various situations and the decisions they make may affect their fitness. The costs and benefits of these responses vary among individuals causing them to differ even in identical situations. One example of this type of situation is when territorial males encounter both a male and female simultaneously, generating a trade-off that likely leads to individual differences due to differing costs of various actions among males. This situation commonly occurs in threespine stickleback, Gasterosteus aculeatus. However, for selection to act effectively, individuals must behave in a consistent manner and measuring repeatability can aid in understanding how selection may shape such trade-offs.Males of this species exhibit consistent individual differences in their response to dummy males and females but it is unknown if patterns are similar when feedback from the stimuli is present. To assess this, male threespine stickleback were tested with dummy and live male and female conspecifics, presented separately and simultaneously. While the same trends were found regardless of stimulus type, males were more aggressive towards the live conspecifics than to the dummies. Repeatability values were similar within a treatment regardless of whether live or dummy conspecifics were used, suggesting that individuals show the same level of consistency. This study adds to our understanding of consistent individual differences by demonstrating that feedback may not affect responses to conflicting stimuli and that male threespine stickleback respond in a consistent manner to both dummy and live stimuli.

  10. INVAZIA GHIDRINULUI – GASTEROSTEUS ACULEATUS LINNAEUS, 1758 ÎN FLUVIUL NISTRU (LIMITELE REPUBLICII MOLDOVA ŞI FACTORII DETERMINANŢI

    Directory of Open Access Journals (Sweden)

    Dumitru BULAT

    2017-03-01

    Full Text Available În condiţiile intensificării presingului antropic în ecosistemele acvatice din Republica Moldova majoritatea speciilor stenobionte au devenit ameninţate cu dispariţia, însă unele, cu potenţial adaptiv înalt, dimpotrivă, pe fonul eliberării nişe­lor spaţiale, pot prolifera în exces şi chiar provoca efect invaziv. Pentru fluviul Nistru (limitele Republicii Moldova un exemplu elocvent este ghidrinul Gasterosteus aculeatus Linnaeus, 1758 care, după construcţia hidrocentralei dela Novodnestrovsk (1981 a devenit o specie multidominantă, formând până la or. Soroca o populaţie locală deosebit de numeroasă.În lucrare sunt analizate particularităţile bioecologice ale ghidrinului şi sunt evidenţiaţi factorii de mediu ce au con­tribuit la invazia taxonului în fl. Nistru (limitele Republicii Moldova.THE INVASION OF THREE-SPINED STICKLEBACK – GASTEROSTEUS ACULEATUS LINNAEUS, 1758 IN DNIESTER RIVER (LIMITS OF REPUBLIC OF MOLDOVA AND ITS DETERINANT FACTORS Under the intensification of anthropogenic pressure in aquatic ecosystems of Republic of Moldova, most of stenobionte species became threatened with extinction, but some species, potentially high adaptive, contrast, in present demonstrates an evident biological progression, in some hydrobiotops causing a stressed invasive effect. For Dniester River (limits of Republic of Moldova three-spined stickleback – Gasterosteus aculeatus Linnaeus, 1758 is a good example, after the construction of Novodnestrovsk hydropower (1981 became a multidominate species forming to Soroca city a particularly large local population.In this paper are analyzed bio- ecological peculiarities of three-spined stickleback and are highlighted environmental factors that contributed to taxon invasion in Dniester River (limits of Republic of Moldova.

  11. COMPARISON OF THE EXPRESSION IN Saccharomyces cerevisiae OF ENDOGLUCANASE II FROM Trichoderma reesei AND ENDOGLUCANASE I FROM Aspergillus aculeatus

    Directory of Open Access Journals (Sweden)

    Weina Zhang,

    2012-07-01

    Full Text Available Two distinct expression cassettes were synthesized by overlapping PCR for expressing the endoglucanase I gene (egl1 from Aspergillus aculeatus and the endoglucanase II gene (egl2 from Trichoderma reesei in a Saccharomyces cerevisiae host. One contained the anchored sequence from the S. cerevisiae cwp2 gene, while the other did not. The low and high copy number plasmids YCplac33 and YEplac195 were used. The enzymatic activities and viscosity changes in the YP-CMC medium varied between the eight recombinant yeast strains produced, and the greatest values were obtained with the YE-TrEII’ strain, which had an activity of 347.7 U/g dry cell weight (DCW and viscosity at 12 h of 4.7% of the initial control value, respectively; YE-TrEII’ was YEplac195-based and contained T. reesei egl2 and no Cwp2 sequence. Strains YC-AaEI and YC-TrEII showed the lowest enzyme activitiy (80.5 and 30.4 U/g DCW, respectively and viscosity changes at 12 h (20.5 and 26.2% of the initial control viscosity, respectively, which were YCplac33-based and contained the Cwp2 sequence. The results showed that gene copy number was the most significant factor to influence the expression of endoglucanases in S. cerevisiae, and the existence of Cwp2 sequence led to decreased enzymatic level and viscosity-reducing performance, while it was shown not to realize efficient surface display of these two endoglucanases.Keywords

  12. Repeatability of decision-making behaviour in male threespine stickleback Gasterosteus aculeatus: Effects of dummy vs. live stimuli

    Directory of Open Access Journals (Sweden)

    Teresa L. DZIEWECZYNSKI, Lindsay M. FORRETTE

    2011-02-01

    Full Text Available Individuals select from a number of behaviours when responding to various situations and the decisions they make may affect their fitness. The costs and benefits of these responses vary among individuals causing them to differ even in identical situations. One example of this type of situation is when territorial males encounter both a male and female simultaneously, gene- rating a trade-off that likely leads to individual differences due to differing costs of various actions among males. This situation commonly occurs in threespine stickleback, Gasterosteus aculeatus. However, for selection to act effectively, individuals must behave in a consistent manner and measuring repeatability can aid in understanding how selection may shape such trade-offs. Males of this species exhibit consistent individual differences in their response to dummy males and females but it is unknown if patterns are similar when feedback from the stimuli is present. To assess this, male threespine stickleback were tested with dummy and live male and female conspecifics, presented separately and simultaneously. While the same trends were found regardless of stimulus type, males were more aggressive towards the live conspecifics than to the dummies. Repeatability values were similar within a treatment regardless of whether live or dummy conspecifics were used, suggesting that individuals show the same level of consistency. This study adds to our understanding of consistent individual differences by demonstrating that feedback may not affect responses to conflicting stimuli and that male threespine stickleback respond in a consistent manner to both dummy and live stimuli [Current Zoology 57 (1: 101–108, 2011].

  13. Utilization of recombinant Trichoderma reesei expressing Aspergillus aculeatus β-glucosidase I (JN11) for a more economical production of ethanol from lignocellulosic biomass.

    Science.gov (United States)

    Treebupachatsakul, Treesukon; Shioya, Koki; Nakazawa, Hikaru; Kawaguchi, Takashi; Morikawa, Yasushi; Shida, Yosuke; Ogasawara, Wataru; Okada, Hirofumi

    2015-12-01

    The capacity of Trichoderma reesei cellulase to degrade lignocellulosic biomass has been enhanced by the construction of a recombinant T. reesei strain expressing Aspergillus aculeatus β-glucosidase I. We have confirmed highly efficient ethanol production from converge-milled Japanese cedar by recombinant T. reesei expressing A. aculeatus β-glucosidase I (JN11). We investigated the ethanol productivity of JN11 and compared it with the cocktail enzyme T. reesei PC-3-7 with reinforced cellobiase activity by the commercial Novozyme 188. Results showed that the ethanol production efficiency under enzymatic hydrolysis of JN11 was comparable to the cocktail enzyme both on simultaneous saccharification and fermentation (SSF) or separate hydrolysis and fermentation (SHF) processes. Moreover, the cocktail enzyme required more protein loading for attaining similar levels of ethanol conversion as JN11. We propose that JN11 is an intrinsically economical enzyme that can eliminate the supplementation of BGL for PC-3-7, thereby reducing the cost of industrial ethanol production from lignocellulosic biomass.

  14. Dicty_cDB: Contig-U02303-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available ) Tachyglossus aculeatus clone TA_Ba-474A7, complet... 46 1.5 1 ( EU587460 ) Ostrea conchaphila clone C125 ...microsatellite sequ... 46 1.5 1 ( EU587458 ) Ostrea conchaphila clone C121 microsatellite sequ... 46 1.5 1 (

  15. In situ effects of metal contamination from former uranium mining sites on the health of the three-spined stickleback (Gasterosteus aculeatus, L.).

    Science.gov (United States)

    Le Guernic, Antoine; Sanchez, Wilfried; Bado-Nilles, Anne; Palluel, Olivier; Turies, Cyril; Chadili, Edith; Cavalié, Isabelle; Delahaut, Laurence; Adam-Guillermin, Christelle; Porcher, Jean-Marc; Geffard, Alain; Betoulle, Stéphane; Gagnaire, Béatrice

    2016-08-01

    Human activities have led to increased levels of various pollutants including metals in aquatic ecosystems. Increase of metallic concentrations in aquatic environments represents a potential risk to exposed organisms, including fish. The aim of this study was to characterize the environmental risk to fish health linked to a polymetallic contamination from former uranium mines in France. This contamination is characterized by metals naturally present in the areas (manganese and iron), uranium, and metals (aluminum and barium) added to precipitate uranium and its decay products. Effects from mine releases in two contaminated ponds (Pontabrier for Haute-Vienne Department and Saint-Pierre for Cantal Department) were compared to those assessed at four other ponds outside the influence of mine tailings (two reference ponds/department). In this way, 360 adult three-spined sticklebacks (Gasterosteus aculeatus) were caged for 28 days in these six ponds before biomarker analyses (immune system, antioxidant system, biometry, histology, DNA integrity, etc.). Ponds receiving uranium mine tailings presented higher concentrations of uranium, manganese and aluminum, especially for the Haute-Vienne Department. This uranium contamination could explain the higher bioaccumulation of this metal in fish caged in Pontabrier and Saint-Pierre Ponds. In the same way, many fish biomarkers (antioxidant and immune systems, acetylcholinesterase activity and biometric parameters) were impacted by this environmental exposure to mine tailings. This study shows the interest of caging and the use of a multi-biomarker approach in the study of a complex metallic contamination.

  16. An overview of the safety evaluation of the Thermomyces lanuginosus xylanase enzyme (SP 628) and the Aspergillus aculeatus xylanase enzyme (SP 578).

    Science.gov (United States)

    Bergman, A; Broadmeadow, A

    1997-01-01

    Xylanases SP 628 and SP 578 were produced by submerged fermentation of Aspergillus oryzae, containing a gene code originating from Thermomyces lanuginosus and Aspergillus aculeatus, respectively. Both enzymes were subject to the same series of toxicological tests to document their safety in use. The enzymes are to be applied as processing aids in the baking industry and in wheat starch separation. Neither enzyme was found to be mutagenic in the Salmonella typhimurium reverse mutation assay, nor did they cause chromosomal aberrations in cultured human peripheral lymphocytes. No evidence of inhalation toxicity or skin and eye irritation was found. The enzymes are not regarded as skin-sensitizers, although the Buehler test with guinea-pigs revealed a minor potential. Oral administration up to 10.0 ml/kg bw/day (equivalent to a Total Organic Solids amount of 13.3% for SP 628 and of 11.3% for SP 578) in 13-week rat studies did not show any adverse effect.

  17. Characterization of mechanisms underlying degradation of sclerotia of Sclerotinia sclerotiorum by Aspergillus aculeatus Asp-4 using a combined qRT-PCR and proteomic approach.

    Science.gov (United States)

    Hu, Xiaojia; Qin, Lu; Roberts, Daniel P; Lakshman, Dilip K; Gong, Yangmin; Maul, Jude E; Xie, Lihua; Yu, Changbing; Li, Yinshui; Hu, Lei; Liao, Xiangsheng; Liao, Xing

    2017-08-31

    The biological control agent Aspergillus aculeatus Asp-4 colonizes and degrades sclerotia of Sclerotinia sclerotiorum resulting in reduced germination and disease caused by this important plant pathogen. Molecular mechanisms of mycoparasites underlying colonization, degradation, and reduction of germination of sclerotia of this and other important plant pathogens remain poorly understood. An RNA-Seq screen of Asp-4 growing on autoclaved, ground sclerotia of S. sclerotiorum for 48 h identified 997 up-regulated and 777 down-regulated genes relative to this mycoparasite growing on potato dextrose agar (PDA) for 48 h. qRT-PCR time course experiments characterized expression dynamics of select genes encoding enzymes functioning in degradation of sclerotial components and management of environmental conditions, including environmental stress. This analysis suggested co-temporal up-regulation of genes functioning in these two processes. Proteomic analysis of Asp-4 growing on this sclerotial material for 48 h identified 26 up-regulated and 6 down-regulated proteins relative to the PDA control. Certain proteins with increased abundance had putative functions in degradation of polymeric components of sclerotia and the mitigation of environmental stress. Our results suggest co-temporal up-regulation of genes involved in degradation of sclerotial compounds and mitigation of environmental stress. This study furthers the analysis of mycoparasitism of sclerotial pathogens by providing the basis for molecular characterization of a previously uncharacterized mycoparasite-sclerotial interaction.

  18. 棘孢曲霉中分离的2个新化合物%Isolation and Identification of Two New Compounds from Aspergillus Aculeatus

    Institute of Scientific and Technical Information of China (English)

    徐燕; 田沙沙; 俞和; 杨文智; 朱华结

    2015-01-01

    从土壤真菌棘孢曲霉( Aspergillus aculeatus)中分离得到2个新化合物和2个已知化合物,采用质谱(MS)、一维核磁共振波谱(1D NMR)、异核多键相关谱(HMBC)、异核单量子相关谱(HSQC)和旋转坐标NOE谱( ROESY)等方法对化合物的结构进行了鉴定,化合物2的顺反构型通过ROESY数据进一步确定。鉴定结果表明,2个新化合物分别为2-(2'-4'-6'-三羟基)-7-羟基-5-甲基色原酮{2-(2',4',6'-trihydroxyphenyl)-(7-hydroxy-5-methyl)chromone}(1)和(E)-4-羟基-3-[(3-甲基-4-羟基-2-丁烯)氧代]苯甲酸{(E)-4-hydroxy-3-[(4-hydroxy-3-methylbut-2-en-1-yl)oxy]benzoic acid}(2);2个已知化合物分别为(S)-2-[(2'-羟基)丙基]-5-甲基-7-羟基色原酮{2-(2'-hydroxypropyl)-5-methyl-7-hydroxychromone}(3)和(3R,4S)-8-羟基-3,4,5-三甲基-6酮-4,6-二氢-3H-异色烯-7-羧酸{(3R,4S)-8-hydroxy-3,4,5-trimethyl-6-oxo-4,6-dihydro-3H-isochromene-7-carbox-ylic acid}(4)。活性测试结果表明,这4个化合物均表现出一定的抗氧化活性。%In order to investigate new bioactive compounds, a piece of fungi Aspergillus aculeatus was obtained from the Jinyun mountain soil in Chongqing, China. By fermentation using Potato Dextrose( PD) within 14 d at 28 ℃, the extraction of ethyl acetate(103 g) was obtained. The extraction was then used for isolation of compounds through a series of study by classical separation methods, for example Octadecyl Silane( ODS) and Sephadex LH-20 . Two new compounds 2-( 2', 4', 6'-trihydroxy phenyl ) benzene-( 7-hydroxy-5-methyl ) chromone ( 1 ) and ( E )-4-hydroxy-3-[ ( 4-hydroxy-3-methylbut-2-en-1-yl ) oxy ] benzoic acid ( 2 ) were obtained. The structures were elucidated using mass spectrometry(MS), one demensional nuclear magnetic resonance spectroscopy ( 1 D NMR ) , heteronuclear multiple bond correlation ( HMQC ) , heteronuclear single quanturn correlation(HMBC) and rotating-frame overhauser effect spectroscopy(ROESY). Other two known compounds 2

  19. Schistocephalus solidus infections increase gonadotropins and gonadotropin releasing hormone (GnRH3) mRNA levels in the three-spined stickleback, Gasterosteus aculeatus.

    Science.gov (United States)

    Shao, Yi Ta; Tseng, Yung Che; Trombley, Susanne; Hwang, Pung Pung; Schmitz, Monika; Borg, Bertil

    2012-09-01

    Parasites often impair the reproduction of their hosts, one well known case being the cestode Schistocephalus solidus which is a common parasite in three-spined sticklebacks, Gasterosteus aculeatus. One of the possible ways that this could be exerted is by suppression on the brain-pituitary-gonadal (BPG) axis. In this study, mRNA levels of FSH-β and LH-β and of GnRH2 (cGnRH II) and GnRH3 (sGnRH) were measured via Q-PCR in infected and uninfected fish sampled from the field a few weeks before the onset of breeding. The pituitary mRNA levels of both FSH-β and LH-β were higher in infected males than in uninfected males. Also in females, FSH-β mRNA levels were higher in infected individuals than in others, whereas there was no significant difference found in LH-β expression. Brain mRNA levels of GnRH3 were higher in infected fish than in uninfected fish in both sexes, but no difference was found in GnRH2 mRNA levels. Thus, infection by S. solidus was able to alter the expressions not only of gonadotropins (GtHs), but also of GnRH which has not been observed previously. However, the effects are opposite to what should be expected if the parasite suppressed reproduction via actions on the brain-pituitary level. The gonads are perhaps more likely to be impaired by the parasites in other ways, and changed feedbacks on the BPG axis could then lead to the increases in GtHs and GnRH.

  20. Did sex chromosome turnover promote divergence of the major mammal groups?: De novo sex chromosomes and drastic rearrangements may have posed reproductive barriers between monotremes, marsupials and placental mammals.

    Science.gov (United States)

    Graves, Jennifer A M

    2016-08-01

    Comparative mapping and sequencing show that turnover of sex determining genes and chromosomes, and sex chromosome rearrangements, accompany speciation in many vertebrates. Here I review the evidence and propose that the evolution of therian mammals was precipitated by evolution of the male-determining SRY gene, defining a novel XY sex chromosome pair, and interposing a reproductive barrier with the ancestral population of synapsid reptiles 190 million years ago (MYA). Divergence was reinforced by multiple translocations in monotreme sex chromosomes, the first of which supplied a novel sex determining gene. A sex chromosome-autosome fusion may have separated eutherians (placental mammals) from marsupials 160 MYA. Another burst of sex chromosome change and speciation is occurring in rodents, precipitated by the degradation of the Y. And although primates have a more stable Y chromosome, it may be just a matter of time before the same fate overtakes our own lineage. Also watch the video abstract. © 2016 The Authors. BioEssays Published by WILEY Periodicals, Inc.

  1. Heterologously expressed Aspergillus aculeatus β-glucosidase in Saccharomyces cerevisiae is a cost-effective alternative to commercial supplementation of β-glucosidase in industrial ethanol production using Trichoderma reesei cellulases.

    Science.gov (United States)

    Treebupachatsakul, Treesukon; Nakazawa, Hikaru; Shinbo, Hideaki; Fujikawa, Hiroki; Nagaiwa, Asami; Ochiai, Nobuhiro; Kawaguchi, Takashi; Nikaido, Mitsuru; Totani, Kazuhide; Shioya, Koki; Shida, Yosuke; Morikawa, Yasushi; Ogasawara, Wataru; Okada, Hirofumi

    2016-01-01

    Trichoderma reesei is a filamentous organism that secretes enzymes capable of degrading cellulose to cellobiose. The culture supernatant of T. reesei, however, lacks sufficient activity to convert cellobiose to glucose using β-glucosidase (BGL1). In this study, we identified a BGL (Cel3B) from T. reesei (TrCel3B) and compared it with the active β-glucosidases from Aspergillus aculeatus (AaBGL1). AaBGL1 showed higher stability and conversion of sugars to ethanol compared to TrCel3B, and therefore we chose to express this recombinant protein for use in fermentation processes. We expressed the recombinant protein in the yeast Saccharomyces cerevisiae, combined it with the superb T. reesei cellulase machinery and used the combination in a simultaneous saccharification and fermentation (SSF) process, with the hope that the recombinant would supplement the BGL activity. As the sugars were processed, the yeast immediately converted them to ethanol, thereby eliminating the problem posed by end product inhibition. Recombinant AaBGL1 activity was compared with Novozyme 188, a commercially available supplement for BGL activity. Our results show that the recombinant protein is as effective as the commercial supplement and can process sugars with equal efficiency. Expression of AaBGL1 in S. cerevisiae increased ethanol production effectively. Thus, heterologous expression of AaBGL1 in S. cerevisiae is a cost-effective and efficient process for the bioconversion of ethanol from lignocellulosic biomass.

  2. Responses of electroreceptors in the snout of the echidna.

    Science.gov (United States)

    Gregory, J E; Iggo, A; McIntyre, A K; Proske, U

    1989-01-01

    1. This is a report of experiments which provide evidence in support of the existence of an electric sense in the echidna, or spiny anteater Tachyglossus aculeatus. It is the first known example of electroreception in a terrestrial animal. 2. In each of four animals anaesthetized with alpha-chloralose, afferent responses were recorded in dissected filaments of the infraorbital branch of the trigeminal nerve which supplies skin of the upper jaw. Recordings were obtained from a total of forty-seven units identified as electroreceptors, by their responses to weak voltage pulses using focal stimulation of the moist skin surface. 3. In the absence of a stimulus, some receptors had an irregular resting discharge; others were silent. The receptive field for each receptor consisted of a discrete spot. Receptive fields were restricted to the tip of the snout. Cathodal stimulation over the receptive spot was excitatory for the duration of an applied voltage pulse. Reversal of stimulus polarity silenced any on-going activity and was followed by a post-anodal rebound excitation. 4. Receptor threshold was best measured not in air but with the snout immersed in tap water. An electric field was applied between a pair of large plate electrodes on either side of the snout. Threshold for thirty receptors lay in the range 1.8-73 mV cm-1. Measurements of response latency and of conduction path length gave estimates of axonal conduction velocities for the afferent fibres of 10-18 m Receptors responded to sinusoidally changing voltage gradients over the range 0.5-200 Hz with a maximum sensitivity at 20 Hz. 5. In one experiment a receptor site was marked with fine pins. Serial sections of the piece of underlying skin revealed a large mucus-secreting gland at the marked spot. Similar glands in skin of the platypus have previously been shown to be the sites of electroreceptors. 6. In a behavioural experiment an echidna was trained to choose between two identical tap water-filled troughs

  3. 一株棘孢曲霉的鉴定及其柚苷酶合成规律%Identification and characterization of Aspergillus aculeatus JMUdb058 for naringinase production

    Institute of Scientific and Technical Information of China (English)

    王迪; 倪辉; 李利君; 陈峰; 肖安风; 蔡慧农; 苏文金

    2013-01-01

    [Objective] A new naringinase-producing strain,JMUdb058 was identified and characterized.[Methods]The strain was identified by morphological observation and 28S rDNA homogeneous analysis.Naringinase was identified by monitoring the hydrolysis of naringin to prunin and naringenin using a reversed phase High Performance Liquid Chromatography (HPLC).The regulation of naringinase expression was studied by measuring naringinase activity of 11 different carbon sources and 7 nitrogen sources in shaking cultivation.The naringinase-producing capacity was investigated in both solid-state fermentation and submerged fermentation.[Results] The macro-morphology and micro-morphology of JMUdb058 corresponded to the characteristics of Aspergillus section Nigri Gams,and the 28S rDNA sequences showed homogeneity at 100% to Aspergillus aculeatus.Crude enzymes prepared by both submerged fermentation and solid-state fermentation could hydrolyze naringin to prunin and naringenin.In addition,the enzyme could remove naringin from citrus juice effectively.Carbon resources,including hesperidin,naringin,rutin and rhamnose,and organic nitrogen resources,i.e.,tryptone,soybean meal,yeast extract and corn syrup were shown to express the naringinase.The strain had an outstanding ability to yield naringinase in the solid-state fermentation,which showed an α-L-rhamnosidase activity of 5903 U/gds by HPLC,and the naringinase of 1939U/gds by HPLC and 72232 U/gds by Davis method.[Conclusion] It is the first time to report a stain of Aspergillus aculeatus can produce naringinase,carbon source containing rhamnose groups are able to induce the enzyme expression.The stain JMUdb058 is a new microorganism source for high yield of naringinase,in particularly by the solid-state fermentation.%[目的]对一株新分离的柚苷酶产生菌株JMUdb058进行鉴定,并研究该菌株柚苷酶合成的基本规律.[方法]利用形态观察、28S rDNA序列分析对JMUdb058进行鉴定;通过反

  4. Consistent individual differences in fathering in threespined stickleback Gasterosteus aculeatus

    Institute of Scientific and Technical Information of China (English)

    Laura R. STEIN; Alison M. BELL

    2012-01-01

    There is growing evidence that individual animals show consistent differences in behavior.For example,individual threespined stickleback fish differ in how they react to predators and how aggressive they are during social interactions with conspecifics.A relatively unexplored but potentially important axis of variation is parental behavior.In sticklebacks,fathers provide all of the parental care that is necessary for offspring survival; therefore paternal care is directly tied to fimess.In this study,we assessed whether individual male sticklebacks differ consistently from each other in parental behavior.We recorded visits to nest,total time fanning,and activity levels of 11 individual males every day throughout one clutch,and then allowed the males to breed again.Half of the males were exposed to predation risk while parenting during the fast clutch,and the other half of the males experienced predation risk during the second clutch.We detected dramatic temporal changes in parental behaviors over the course of the clutch:for example,total time fanning increased six-fold prior to eggs hatching,then decreased to approximately zero.Despite these temporal changes,males retained their individually-distinctive parenting styles within a clutch that could not be explained by differences in body size or egg mass.Moreover,individual differences in parenting were maintained when males reproduced for a second time.Males that were exposed to simulated predation risk briefly decreased fanning and increased activity levels.Altogether,these results show that individual sticklebacks consistently differ from each other in how they behave as parents [Current Zoology 58 (1):45-52,2012].

  5. Consistent individual differences in fathering in threespined stickleback Gasterosteus aculeatus

    Directory of Open Access Journals (Sweden)

    Laura R. STEIN, Alison M. BELL

    2012-02-01

    Full Text Available There is growing evidence that individual animals show consistent differences in behavior. For example, individual threespined stickleback fish differ in how they react to predators and how aggressive they are during social interactions with conspecifics. A relatively unexplored but potentially important axis of variation is parental behavior. In sticklebacks, fathers provide all of the parental care that is necessary for offspring survival; therefore paternal care is directly tied to fitness. In this study, we assessed whether individual male sticklebacks differ consistently from each other in parental behavior. We recorded visits to nest, total time fanning, and activity levels of 11 individual males every day throughout one clutch, and then allowed the males to breed again. Half of the males were exposed to predation risk while parenting during the first clutch, and the other half of the males experienced predation risk during the second clutch. We detected dramatic temporal changes in parental behaviors over the course of the clutch: for example, total time fanning increased six-fold prior to eggs hatching, then decreased to approximately zero. Despite these temporal changes, males retained their individually-distinctive parenting styles within a clutch that could not be explained by differences in body size or egg mass. Moreover, individual differences in parenting were maintained when males reproduced for a second time. Males that were exposed to simulated predation risk briefly decreased fanning and increased activity levels. Altogether, these results show that individual sticklebacks consistently differ from each other in how they behave as parents [Current Zoology 58 (1: 45–52, 2012].

  6. Costly plastic morphological responses to predator specific odour cues in three-spined sticklebacks (Gasterosteus aculeatus)

    NARCIS (Netherlands)

    Frommen, Joachim G.; Herder, Fabian; Engqvist, Leif; Mehlis, Marion; Bakker, Theo C. M.; Schwarzer, Julia; Thuenken, Timo

    Predation risk is one of the major forces affecting phenotypic variation among and within animal populations. While fixed anti-predator morphologies are favoured when predation level is consistently high, plastic morphological responses are advantageous when predation risk is changing temporarily,

  7. Influence of ethylenediaminetetraacetic acid (EDTA) on the structural stability of endoglucanase from Aspergillus aculeatus.

    Science.gov (United States)

    Naika, Gajendra S; Tiku, Purnima Kaul

    2011-07-13

    The effect of the chelating agent ethylenediaminetetraacetic acid (EDTA) on the structure and function of endoglucanase is studied. In the presence of 2 mM EDTA, endoglucanase showed an enhanced enzymatic activity of 1.5-fold compared to control. No further change in activity was observed with increase in the concentration of EDTA to 5 mM. The K(m) values for control and in the presence of EDTA are 0.060 and 0.044%, respectively, and K(cat) was 1.9 min(-1) in the presence of EDTA. The kinetic parameters indicated a decrease in the K(m) with an increase in the K(cat). Far-ultraviolet circular dichroism (far-UV-CD) results showed a 20% decrease in ellipticity values at 217 nm in the presence of EDTA compared to native enzyme. The apparent T(m) shifted from a control value of 57 ± 1 to 76 ± 1 °C in the presence of EDTA (5 mM). The above results suggested that the enhanced activity in the presence of EDTA is due to an increase in the K(cat) and flexible conformation of the enzyme. The stability of endoglucanase increased in the presence of EDTA.

  8. Fructooligosaccharides synthesis by highly stable immobilized beta-fructofuranosidase from Aspergillus aculeatus

    NARCIS (Netherlands)

    Soibelmann Glock Lorenzoni, André; Aydos, Luiza F.; Klein, Manuela P.; Rodrigues, Rafael C.; Hertz, Plinho F.

    2014-01-01

    The enzymatic synthesis of fructooligosaccharides (FOS) was carried out using a partially purified beta-fructofuranosidase from the commercial enzyme preparation Viscozyme L. Partial purification of beta-fructofuranosidase from Viscozyme L was done by batch adsorption using ion-exchange resin DEAE-S

  9. Landscape genetics of Schistocephalus solidus parasites in threespine stickleback (Gasterosteus aculeatus from Alaska.

    Directory of Open Access Journals (Sweden)

    C Grace Sprehn

    Full Text Available The nature of gene flow in parasites with complex life cycles is poorly understood, particularly when intermediate and definitive hosts have contrasting movement potential. We examined whether the fine-scale population genetic structure of the diphyllobothriidean cestode Schistocephalus solidus reflects the habits of intermediate threespine stickleback hosts or those of its definitive hosts, semi-aquatic piscivorous birds, to better understand complex host-parasite interactions. Seventeen lakes in the Cook Inlet region of south-central Alaska were sampled, including ten in the Matanuska-Susitna Valley, five on the Kenai Peninsula, and two in the Bristol Bay drainage. We analyzed sequence variation across a 759 bp region of the mitochondrial DNA (mtDNA cytochrome oxidase I region for 1,026 S. solidus individuals sampled from 2009-2012. We also analyzed allelic variation at 8 microsatellite loci for 1,243 individuals. Analysis of mtDNA haplotype and microsatellite genotype variation recovered evidence of significant population genetic structure within S. solidus. Host, location, and year were factors in structuring observed genetic variation. Pairwise measures revealed significant differentiation among lakes, including a pattern of isolation-by-distance. Bayesian analysis identified three distinct genotypic clusters in the study region, little admixture within hosts and lakes, and a shift in genotype frequencies over time. Evidence of fine-scale population structure in S. solidus indicates that movement of its vagile, definitive avian hosts has less influence on gene flow than expected based solely on movement potential. Observed patterns of genetic variation may reflect genetic drift, behaviors of definitive hosts that constrain dispersal, life history of intermediate hosts, and adaptive specificity of S. solidus to intermediate host genotype.

  10. A flexible whole-genome microarray for transcriptomics in three-spine stickleback (Gasterosteus aculeatus

    Directory of Open Access Journals (Sweden)

    Primmer Craig R

    2009-09-01

    Full Text Available Abstract Background The use of microarray technology for describing changes in mRNA expression to address ecological and evolutionary questions is becoming increasingly popular. Since three-spine stickleback are an important ecological and evolutionary model-species as well as an emerging model for eco-toxicology, the ability to have a functional and flexible microarray platform for transcriptome studies will greatly enhance the research potential in these areas. Results We designed 43,392 unique oligonucleotide probes representing 19,274 genes (93% of the estimated total gene number, and tested the hybridization performance of both DNA and RNA from different populations to determine the efficacy of probe design for transcriptome analysis using the Agilent array platform. The majority of probes were functional as evidenced by the DNA hybridization success, and 30,946 probes (14,615 genes had a signal that was significantly above background for RNA isolated from liver tissue. Genes identified as being expressed in liver tissue were grouped into functional categories for each of the three Gene Ontology groups: biological process, molecular function, and cellular component. As expected, the highest proportions of functional categories belonged to those associated with metabolic functions: metabolic process, binding, catabolism, and organelles. Conclusion The probe and microarray design presented here provides an important step facilitating transcriptomics research for this important research organism by providing a set of over 43,000 probes whose hybridization success and specificity to liver expression has been demonstrated. Probes can easily be added or removed from the current design to tailor the array to specific experiments and additional flexibility lies in the ability to perform either one-color or two-color hybridizations.

  11. Phenotypic plasticity of the threespine stickleback Gasterosteus aculeatus telencephalon in response to experience in captivity

    Directory of Open Access Journals (Sweden)

    Peter J. PARK, Ivan CHASE, Michael A. BELL

    2012-02-01

    Full Text Available Threespine stickleback were used to examine phenotypic plasticity of telencephala in relation to inferred ecology. Fish from derived, allopatric, freshwater populations were sampled from three shallow, structurally complex lakes with benthic-foraging stickleback (benthics and from three deep, structurally simple lakes with planktivores (limnetics. The telencephalon of specimens preserved immediately after capture (field-preserved, field-caught fish held in aquaria for 90 days (lab-held, and lab-bred fish from crosses and raised in aquaria were compared. Field-preserved sea-run (ancestral stickleback were collected from two separate sites, and parents of lab-bred sea-run stickleback were collected from one of these sites. In field-preserved and lab-held fish, the telencephala of limnetics exhibited triangular dorsal shape, while those of benthics and sea-run fish had rounder shapes. No such pattern was detected in lab-bred fish. Within each treatment type, benthics had larger relative telencephalon sizes, using overall brain size as the covariate, than limnetics. Among field-preserved samples, sea-run fish had smaller telencephalon sizes than lake fish. Intra-population analyses of lake samples showed that field-preserved fish consistently had larger relative telencephalon sizes than lab-bred fish. The opposite was true of the sea-run population. In a separate study using one benthic population and one limnetic population, samples were preserved in the field immediately or held in the lab for 30, 60, and 90 days before they were sacrificed. In both populations, the telencephalon shapes of lab-held fish were similar to those of field-preserved fish but became progressively more like lab-bred ones over 90 days. In contrast, relative telencephalon size decreased dramatically by 30 days after which there was little change. In freshwater threespine stickleback, the telencephalon exhibits considerable phenotypic plasticity, which was probably present in the ancestor [Current Zoology 58 (1: 189–210, 2012].

  12. Housekeeping genes for quantitative expression studies in the three-spined stickleback Gasterosteus aculeatus

    NARCIS (Netherlands)

    Hibbeler, S.; Scharsack, J.P.; Becker, S.

    2008-01-01

    Background During the last years the quantification of immune response under immunological challenges, e.g. parasitation, has been a major focus of research. In this context, the expression of immune response genes in teleost fish has been surveyed for scientific and commercial purposes. Despite the

  13. Housekeeping genes for quantitative expression studies in the three-spined stickleback Gasterosteus aculeatus

    NARCIS (Netherlands)

    Hibbeler, S.; Scharsack, J.P.; Becker, S.

    2008-01-01

    Background During the last years the quantification of immune response under immunological challenges, e.g. parasitation, has been a major focus of research. In this context, the expression of immune response genes in teleost fish has been surveyed for scientific and commercial purposes. Despite the

  14. Housekeeping genes for quantitative expression studies in the three-spined stickleback Gasterosteus aculeatus

    OpenAIRE

    Becker Sven; Scharsack Joern P; Hibbeler Sascha

    2008-01-01

    Abstract Background During the last years the quantification of immune response under immunological challenges, e.g. parasitation, has been a major focus of research. In this context, the expression of immune response genes in teleost fish has been surveyed for scientific and commercial purposes. Despite the fact that it was shown in teleostei and other taxa that the gene for beta-actin is not the most stably expressed housekeeping gene (HKG), depending on the tissue and experimental treatmen...

  15. Infection-dependent MHC expression in the three-spined stickleback, Gasterosteus aculeatus

    OpenAIRE

    Hibbeler, S.

    2006-01-01

    The study focused on two main topics. On the one hand primers and a PCR protocol were developed to find a suitable housekeeping gene for quantitative real-time PCR. On the other hand this study explored the expression of genes related to an immune response in cell cultures and organs of living fish. The main focus lay on the genes of the major histocompatibility complex (MHC). The MHC has been studied for several years. This is mainly because of the central role of MHC molecules in the adapti...

  16. Individual variation in habituation: behaviour over time toward different stimuli in threespine sticklebacks (Gasterosteus aculeatus)

    OpenAIRE

    Bell, Alison M.; Peeke, Harman V.S.

    2012-01-01

    Habituation, or the relatively permanent waning of a response as a result of repeated stimulation, is a form of behavioural plasticity that allows animals to filter out irrelevant stimuli and to focus selectively on important stimuli. Individuals that fail to habituate might be at a disadvantage if they continue to respond to irrelevant stimuli; therefore, habituation can have adaptive significance. In this study we compared rates of behaviour over time toward three different ecologically-rel...

  17. Phenotypic plasticity of the threespine stickleback Gasterosteus aculeatus telencephalon in response to experience in captivity

    Institute of Scientific and Technical Information of China (English)

    Peter J. PARK; Ivan CHASE; Michael A. BELL

    2012-01-01

    Threespine stickleback were used to examine phenotypic plasticity of telencephala in relation to inferred ecology.Fish from derived,allopatric,freshwater populations were sampled from three shallow,structurally complex lakes with benthic-foraging stickleback (benthics) and from three deep,structurally simple lakes with planktivores (limnetics).The telencephaIon of specimens preserved immediately after capture (field-preserved),field-caught fish held in aquaria for 90 days (lab-held),and lab-bred fish from crosses and raised in aquaria were compared.Field-preserved sea-run (ancestral) stickleback were collected from two separate sites,and parents of lab-bred sea-run stickleback were collected from one of these sites.In field-preserved and lab-held fish,the telencephala of limnetics exhibited triangular dorsal shape,while those of benthics and sea-run fish had rounder shapes.No such pattern was detected in lab-bred fish.Within each treatment type,benthics had larger relative telencephalon sizes,using overall brain size as the covariate,than limnetics.Among field-preserved samples,sea-run fish had smaller telencephalon sizes than lake fish.Intra-population analyses of lake samples showed that field-preserved fish consistently had larger relative telencephalon sizes than lab-brel fish.The opposite was true of the sea-run population.In a separate study using one benthic population and one linnetic population,samples were preserved in the field immediately or held in the lab for 30,60,and 90 days before they were sacrificed.In both populations,the telencephalon shapes of lab-held fish were similar to those of field-preserved fish but became progressively more like lab-bred ones over 90 days.In contrast,relative telencephalon size decreased dramatically by 30 days after which there was little change.In freshwater threespine stickleback,the telencephalon exhibits considerable phenotypic plasticity,which was probably present in the ancestor [Current Zoology 58 (1):189-210,2012].

  18. Marsupial and monotreme serum immunoglobulin binding by proteins A, G and L and anti-kangaroo antibody.

    Science.gov (United States)

    Vaz, Paola K; Hartley, Carol A; Browning, Glenn F; Devlin, Joanne M

    2015-12-01

    Serological studies are often conducted to examine exposure to infectious agents in wildlife populations. However, specific immunological reagents for wildlife species are seldom available and can limit the study of infectious diseases in these animals. This study examined the ability of four commercially available immunoglobulin-binding reagents to bind serum immunoglobulins from 17 species within the Marsupialia and Monotremata. Serum samples were assessed for binding, using immunoblots and ELISAs (Enzyme-linked immunosorbent assays), to three microbially-derived proteins - staphylococcal protein A, streptococcal protein G and peptostreptococcal protein L. Additionally, an anti-kangaroo antibody was included for comparison. The inter- and intra-familial binding patterns of the reagents to serum immunoglobulins varied and evolutionary distance between animal species was not an accurate predictor of the ability of reagents to bind immunoglobulins. Results from this study can be used to inform the selection of appropriate immunological reagents in future serological studies in these clades.

  19. Taxonomy Icon Data: three-spined stickleback [Taxonomy Icon

    Lifescience Database Archive (English)

    Full Text Available three-spined stickleback Gasterosteus aculeatus Chordata/Vertebrata/Pisciformes Gasteros...teus_aculeatus_L.png Gasterosteus_aculeatus_NL.png Gasterosteus_aculeatus_S.png Gasterosteus_aculeatus_...NS.png http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Gasterosteus+aculeatus&t=L http://biosciencedbc.jp/t...axonomy_icon/icon.cgi?i=Gasterosteus+aculeatus&t=NL http://biosciencedbc.jp/taxon...omy_icon/icon.cgi?i=Gasterosteus+aculeatus&t=S http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Gasterosteus+aculeatus&t=NS ...

  20. Characterization of antibodies for quantitative determination of spiggin protein levels in male and female three-spined stickleback (Gasterosteus aculeatus

    Directory of Open Access Journals (Sweden)

    Karlsson Johnny

    2009-05-01

    Full Text Available Abstract Spiggin is an adhesive glycoprotein produced in the kidney of sticklebacks during the breeding season and is subsequently secreted into the urinary bladder from where it is employed for nest building. Since the production of the protein has been shown to be under androgenic control, spiggin has been suggested to be a useful biomarker for androgenic substances in the environment. In this study, two polyclonal spiggin antibodies based on synthetic peptides and one polyclonal antibody directed against native spiggin have been characterized. The antibodies ability to identify spiggin was investigated by quantitative immunoassay. For both peptide antibodies the quantification range was determined to be between 1 and 80 ng spiggin and determination of renal spiggin levels from immature and mature males displayed a 15-fold increase in total spiggin content of the kidney resulting in a 6-fold increase in male kidney weight due to hypertrophy. The kidney somatic index (KSI was found to correlate well with the total renal spiggin content and therefore it appears that KSI in sticklebacks could be used as an initial method to identify substances displaying androgenic effects. Furthermore, western blot analysis revealed that the polyclonal antibodies recognize different spiggin isoforms and that spiggin can be detected in the urinary bladder and kidney of both males and female sticklebacks. In order to develop a quantitative detection method for native spiggin it is necessary to produce a standard that can be used in a bioassay. Due to the adhesive and polymerization characteristics of spiggin the protein is difficult to use as a standard in bioassays. So far spiggin has been shown to exist in at least 14 isoforms, all of which contain polymerization domains. To overcome the solubility problem we have produced recombinant spiggin gamma, with only one polymerization domain, that can be expressed in E. coli. Western blot analysis demonstrated that the polyclonal antibodies were able to detect recombinant spiggin gamma protein in bacterial cell lysate, suggesting that it may be developed into a useful source of standard spiggin to be used for quantitative determination of androgen induced spiggin production in sticklebacks.

  1. A low-density SNP array for analyzing differential selection in freshwater and marine populations of threespine stickleback (Gasterosteus aculeatus)

    DEFF Research Database (Denmark)

    Ferchaud, Anne-Laure; Pedersen, Susanne H.; Bekkevold, Dorte

    2014-01-01

    have developed a cost-efficient low-density SNP array that allows for rapid screening of polymorphisms in threespine stickleback. The array provides a valuable tool for analyzing adaptive divergence between freshwater and marine stickleback populations beyond the well-established candidate gene...... stickleback populations at the phenotypic trait of lateral plate morphology and the underlying candidate gene Ectodysplacin (EDA). Many studies have focused on this trait and candidate gene, although other genes involved in marine-freshwater adaptation may be equally important. In order to develop a resource...... for rapid and cost efficient analysis of genetic divergence between freshwater and marine sticklebacks, we generated a low-density SNP (Single Nucleotide Polymorphism) array encompassing markers of chromosome regions under putative directional selection, along with neutral markers for background. Results...

  2. Non-parallel divergence across Danish freshwater and marine three-spined stickleback Gasterosteus aculeatus populations

    DEFF Research Database (Denmark)

    Pujolar, José Martin; Ferchaud, Anne-Laure; Bekkevold, Dorte

    2017-01-01

    at 13 sampling locations were screened for genetic variation using a combination of 70 genes putatively under selection and 26 neutral genes along with a marker linked to the ectodysplasin gene(eda), which is strongly correlated with plate armour morphs in the species. A highly significant genetic...

  3. Altered neurotransmitter function in CO2-exposed stickleback (Gasterosteus aculeatus): a temperate model species for ocean acidification research.

    Science.gov (United States)

    Lai, Floriana; Jutfelt, Fredrik; Nilsson, Göran E

    2015-01-01

    Studies on the consequences of ocean acidification for the marine ecosystem have revealed behavioural changes in coral reef fishes exposed to sustained near-future CO2 levels. The changes have been linked to altered function of GABAergic neurotransmitter systems, because the behavioural alterations can be reversed rapidly by treatment with the GABAA receptor antagonist gabazine. Characterization of the molecular mechanisms involved would be greatly aided if these can be examined in a well-characterized model organism with a sequenced genome. It was recently shown that CO2-induced behavioural alterations are not confined to tropical species, but also affect the three-spined stickleback, although an involvement of the GABAA receptor was not examined. Here, we show that loss of lateralization in the stickleback can be restored rapidly and completely by gabazine treatment. This points towards a worrying universality of disturbed GABAA function after high-CO2 exposure in fishes from tropical to temperate marine habitats. Importantly, the stickleback is a model species with a sequenced and annotated genome, which greatly facilitates future studies on underlying molecular mechanisms.

  4. Sexual maturation and changes in water and salt transport components in the kidney and intestine of three-spined stickleback (Gasterosteus aculeatus L.).

    Science.gov (United States)

    Madsen, Steffen S; Weber, Claus; Nielsen, Andreas M; Mohiseni, Mohammad; Bosssus, Maryline C; Tipsmark, Christian K; Borg, Bertil

    2015-10-01

    Mature three-spined stickleback males use spiggin threads secreted from their kidney to glue together nest material. This requires strongly hypertrophied renal proximal tubular cells, which compromises renal osmoregulatory function during the breeding period. Experimental evidence suggests that the intestine takes over hypotonic fluid secretion at that stage but the mechanism is unexplored. To unravel the molecular mechanism we analyzed and compared transcript levels of several membrane proteins involved in water and salt transport in intestinal and renal tissues, in non-mature males (NM), mature males (MM), and mature females (MF). Aquaporin paralogs aqp1a, -3a, -8aa, -8ab, -10a, and -10b, two Na(+),K(+)-ATPase alpha-1 subunit isoforms (nka547, nka976), Na(+),K(+),2Cl(-)-, and Na(+),Cl(-)-cotransporters (nkcc1a, nkcc2, ncc), the cystic fibrosis transmembrane conductance regulator (cftr) and two claudin isoforms (cldn2, cldn15a) were expressed in the intestine and kidney in all groups. There were no differences in aqp and cldn expression between intestines of NM and MM; nkcc2 was lower and nka levels tended to be higher in intestines of MM than in NM. In the kidney, aqp1 and aqp8ab levels were lower in MM than in NM, whereas aqp3a, nkcc1a, cldn15a, and spiggin were markedly elevated. This was accompanied by marked hypertrophy of kidney tubules in MM. The data support an altered kidney function in terms of water handling in mature males, whereas there was no support for modified trans-epithelial water permeability or salt-secretory activity in the intestine of mature males. Salt-absorptive activity in the intestine may, however, be down-regulated during male maturation.

  5. Waterborne citalopram has anxiolytic effects and increases locomotor activity in the three-spine stickleback (Gasterosteus aculeatus)

    DEFF Research Database (Denmark)

    Kellner, M; Porseryd, T; Hallgren, S;

    2016-01-01

    to analyse different aspects of behavioural effects of chronic citalopram exposure in fish. Our model species the three-spine stickleback is common in the entire northern hemisphere and is considered to be a good environmental sentinel species. Female three-spine sticklebacks were exposed to 0, 1.5 and 15μg...

  6. Androgen receptor-beta mRNA levels in different tissues in breeding and post-breeding male and female sticklebacks, Gasterosteus aculeatus

    Directory of Open Access Journals (Sweden)

    Hoffmann Erik

    2012-03-01

    Full Text Available Abstract Background Androgens induce male characters by activating androgen receptors (AR. Previous quantitative studies on AR in fishes have been limited to few tissues and/or a single season/reproductive state. The aim of this investigation was to study the possible role of AR-beta expression levels in the control of male traits in the three-spined stickleback. To that end, AR-beta expression levels in major tissues in breeding and post-breeding male and female sticklebacks were examined. Methods AR-beta mRNA levels were quantified in ten tissues; eye, liver, axial muscle, heart, brain, intestine, ovary, testis, kidney and pectoral muscle in six breeding and post-breeding males and females using reverse transcription quantitative PCR. Results Breeding in contrast to post-breeding males built nests and showed secondary sexual characters (e.g. kidney hypertrophy and elevated androgen levels. Post-breeding females had lower ovarian weights and testosterone levels than breeding females. AR-beta was expressed in all studied tissues in both sexes and reproductive states with the highest expression in the gonads and in the kidneys. The kidney is an androgen target organ in sticklebacks, from which breeding males produce the protein spiggin, which is used in nest-building. There was also high AR-beta expression in the intestine, an organ that appears to take over hyperosmo-regulation in fresh water when the kidney hypertrophies in mature males and largely loses this function. The only tissue that showed effects of sex or reproductive state on AR-beta mRNA levels was the kidneys, where post-breeding males displayed higher AR-beta mRNA levels than breeding males. Conclusion The results indicate that changes in AR-beta mRNA levels play no or little role in changes in androgen dependent traits in the male stickleback.

  7. Energetics of median and paired fin swimming, body and caudal fin swimming, and gait transition in parrotfish (Scarus schlegeli) and triggerfish (Rhinecanthus aculeatus)

    DEFF Research Database (Denmark)

    Korsmeyer, Keith E; Steffensen, John Fleng; Herskin, Jannik

    2002-01-01

    exclusively with the pectoral fins at prolonged swimming speeds up to 3.2 total lengths per second (L s(-1); 30 min critical swimming speed, U(crit)). At higher speeds, gait transferred to a burst-and-coast BCF swimming mode that resulted in rapid fatigue. The triggerfish swam using undulations of the soft...... dorsal and anal fins up to 1.5 L s(-1), beyond which BCF undulations were recruited intermittently. BCF swimming was used continuously above 3.5 L s(-1), and was accompanied by synchronous undulations of the dorsal and anal fins. The triggerfish were capable of high, prolonged swimming speeds of up to 4...

  8. The Relationship between the Ionic Composition of the Environment and the Secretory Activity of the Endocrine Cell Types of Stannius Corpuscles in the Teleost Gasterosteus aculeatus

    NARCIS (Netherlands)

    Wendelaar Bonga, S.E.; Greven, J.A.A.; Veenhuis, M.

    1976-01-01

    The corpuscles of Stannius of threespined sticklebacks contain two glandular cell types of presumed endocrine nature. To elucidate the function of both cell types the secretory activity of the cells was studied in fully adapted seawater and freshwater fishes and in specimens transferred from sea

  9. Biological conversion of stevioside to steviol by Aspergillus aculeatus and the purification of rebaudioside A%棘孢曲霉转化甜菊糖为甜菊醇及纯化莱鲍迪苷A

    Institute of Scientific and Technical Information of China (English)

    马迎迎; 陈育如; 张伟娜; 孙欢; 夏文静

    2014-01-01

    [目的]本工作对棘孢曲霉固体发酵抽提酶液转化甜菊糖进行了研究,并对转化产物进行鉴定及纯化分析.[方法]用高效液相色谱、液质联用及红外光谱等方法对转化新产物进行鉴定,对上清液中莱鲍迪苷A(RA)成分进行纯化.[结果]棘孢曲霉酶液在10 h内对甜菊糖中的甜菊苷(SS)、莱鲍迪苷C(RC)进行高效特异性转化,以沉淀的形式析出的转化产物经鉴定为甜菊醇,转化率高达98.0%,分离提纯后纯度为95.2%,回收率达84.0%.由于甜菊醇的沉淀分离,留在溶液中的RA更易被纯化.RA通过树脂吸附分离的回收率为80.5%.[结论]棘孢曲霉酶液对甜菊糖的一次转化可以同时得到甜菊醇和莱鲍迪苷A两种产品,是一种经济高效的工艺.

  10. Histological observations on presumed electroreceptors and mechanoreceptors in the beak skin of the long-beaked echidna, Zaglossus bruijnii.

    Science.gov (United States)

    Manger, P. R.; Collins, R.; Pettigrew, J. D.

    1997-01-01

    Sensory receptors in the rostral portion of the beak skin of a single specimen of the rare long-beaked echidna, Zaglossus bruijnii, are described. Mucous glands which have been modified to accommodate sensory innervation, similar to those seen in Ornithorhynchus, are found in the rostral 2 cm of the beak skin, anterior to the maxillofacial foramen, at a density of approximately 12/mm2. The papillary epidermal portion of the gland ducts are walled by concentric layers of keratinocytes, and each duct is innervated by 10–15 myelinated nerve terminals. The mucous gland receptors in Zaglossus are intermediate in structure between those of Ornithorhynchus and Tachyglossus, but are similar enough to the former to suggest that electroreception may play a major role in the sensory experience of Zaglossus. Push-rod mechanoreceptors also occur throughout the same region of beak skin, and appear similar to those described for Tachyglossus.

  11. Parallel Genetic Basis for Repeated Evolution of Armor Loss in Alaskan Threespine Stickleback Populations

    National Research Council Canada - National Science Library

    William A. Cresko; Angel Amores; Catherine Wilson; Joy Murphy; Mark Currey; Patrick Phillips; Michael A. Bell; Charles B. Kimmel; John H. Postlethwait; David B. Wake

    2004-01-01

    ... alleles at a small number of loci. To address this question, we examined the genetic basis of bony armor loss in three freshwater populations of Alaskan threespine stickleback, Gasterosteus aculeatus, that evolved from fully armored...

  12. Correlates of red throat coloration in female stickleback and their potential evolutionary significance

    NARCIS (Netherlands)

    Yong, Lengxob; Guo, Ruqing; Wright, Daniel S.; Mears, Samantha A.; Pierotti, Michele; McKinnon, Jeffrey S.

    Background: In two stream-resident populations of threespine stickleback (Gasterosteus aculeatus), females often exhibit male-typical red throat coloration. These fish inhabit the Little Campbell River (British Columbia) and Matadero Creek (California). An anadromous population that lacks such

  13. Male red throat coloration, pelvic spine coloration, and courtship behaviours in threespine stickleback

    NARCIS (Netherlands)

    Wright, Daniel Shane; Yong, Lengxob; Pierotti, Michele E. R.; McKinnon, Jeffrey S.

    Background: In addition to exhibiting red nuptial throat coloration, male threespine sticklebacks (Gasterosteus aculeatus) often possess red coloration on their pelvic spines. Although variation in throat colour has been shown to be associated with male reproductive behaviour, limited research has

  14. Genome analysis of the platypus reveals unique signatures of evolution.

    Science.gov (United States)

    Warren, Wesley C; Hillier, LaDeana W; Marshall Graves, Jennifer A; Birney, Ewan; Ponting, Chris P; Grützner, Frank; Belov, Katherine; Miller, Webb; Clarke, Laura; Chinwalla, Asif T; Yang, Shiaw-Pyng; Heger, Andreas; Locke, Devin P; Miethke, Pat; Waters, Paul D; Veyrunes, Frédéric; Fulton, Lucinda; Fulton, Bob; Graves, Tina; Wallis, John; Puente, Xose S; López-Otín, Carlos; Ordóñez, Gonzalo R; Eichler, Evan E; Chen, Lin; Cheng, Ze; Deakin, Janine E; Alsop, Amber; Thompson, Katherine; Kirby, Patrick; Papenfuss, Anthony T; Wakefield, Matthew J; Olender, Tsviya; Lancet, Doron; Huttley, Gavin A; Smit, Arian F A; Pask, Andrew; Temple-Smith, Peter; Batzer, Mark A; Walker, Jerilyn A; Konkel, Miriam K; Harris, Robert S; Whittington, Camilla M; Wong, Emily S W; Gemmell, Neil J; Buschiazzo, Emmanuel; Vargas Jentzsch, Iris M; Merkel, Angelika; Schmitz, Juergen; Zemann, Anja; Churakov, Gennady; Kriegs, Jan Ole; Brosius, Juergen; Murchison, Elizabeth P; Sachidanandam, Ravi; Smith, Carly; Hannon, Gregory J; Tsend-Ayush, Enkhjargal; McMillan, Daniel; Attenborough, Rosalind; Rens, Willem; Ferguson-Smith, Malcolm; Lefèvre, Christophe M; Sharp, Julie A; Nicholas, Kevin R; Ray, David A; Kube, Michael; Reinhardt, Richard; Pringle, Thomas H; Taylor, James; Jones, Russell C; Nixon, Brett; Dacheux, Jean-Louis; Niwa, Hitoshi; Sekita, Yoko; Huang, Xiaoqiu; Stark, Alexander; Kheradpour, Pouya; Kellis, Manolis; Flicek, Paul; Chen, Yuan; Webber, Caleb; Hardison, Ross; Nelson, Joanne; Hallsworth-Pepin, Kym; Delehaunty, Kim; Markovic, Chris; Minx, Pat; Feng, Yucheng; Kremitzki, Colin; Mitreva, Makedonka; Glasscock, Jarret; Wylie, Todd; Wohldmann, Patricia; Thiru, Prathapan; Nhan, Michael N; Pohl, Craig S; Smith, Scott M; Hou, Shunfeng; Nefedov, Mikhail; de Jong, Pieter J; Renfree, Marilyn B; Mardis, Elaine R; Wilson, Richard K

    2008-05-08

    We present a draft genome sequence of the platypus, Ornithorhynchus anatinus. This monotreme exhibits a fascinating combination of reptilian and mammalian characters. For example, platypuses have a coat of fur adapted to an aquatic lifestyle; platypus females lactate, yet lay eggs; and males are equipped with venom similar to that of reptiles. Analysis of the first monotreme genome aligned these features with genetic innovations. We find that reptile and platypus venom proteins have been co-opted independently from the same gene families; milk protein genes are conserved despite platypuses laying eggs; and immune gene family expansions are directly related to platypus biology. Expansions of protein, non-protein-coding RNA and microRNA families, as well as repeat elements, are identified. Sequencing of this genome now provides a valuable resource for deep mammalian comparative analyses, as well as for monotreme biology and conservation.

  15. Sex determination in mammals--before and after the evolution of SRY.

    Science.gov (United States)

    Wallis, M C; Waters, P D; Graves, J A M

    2008-10-01

    Therian mammals (marsupials and placentals) have an XX female: XY male sex chromosome system, which is homologous to autosomes in other vertebrates. The testis-determining gene, SRY, is conserved on the Y throughout therians, but is absent in other vertebrates, suggesting that the mammal system evolved about 310 million years ago (MYA). However, recent work on the basal monotreme mammals has completely changed our conception of how and when this change occurred. Platypus and echidna lack SRY, and the therian X and Y are represented by autosomes, implying that SRY evolved in therians after their divergence from monotremes only 166 MYA. Clues to the ancestral mechanism usurped by SRY in therians are provided by the monotremes, whose sex chromosomes are homologous to the ZW of birds. This suggests that the therian X and Y, and the SRY gene, evolved from an ancient bird-like sex chromosome system which predates the divergence of mammals and reptiles 310 MYA.

  16. Genome analysis of the platypus reveals unique signatures of evolution

    Science.gov (United States)

    Warren, Wesley C.; Hillier, LaDeana W.; Marshall Graves, Jennifer A.; Birney, Ewan; Ponting, Chris P.; Grützner, Frank; Belov, Katherine; Miller, Webb; Clarke, Laura; Chinwalla, Asif T.; Yang, Shiaw-Pyng; Heger, Andreas; Locke, Devin P.; Miethke, Pat; Waters, Paul D.; Veyrunes, Frédéric; Fulton, Lucinda; Fulton, Bob; Graves, Tina; Wallis, John; Puente, Xose S.; López-Otín, Carlos; Ordóñez, Gonzalo R.; Eichler, Evan E.; Chen, Lin; Cheng, Ze; Deakin, Janine E.; Alsop, Amber; Thompson, Katherine; Kirby, Patrick; Papenfuss, Anthony T.; Wakefield, Matthew J.; Olender, Tsviya; Lancet, Doron; Huttley, Gavin A.; Smit, Arian F. A.; Pask, Andrew; Temple-Smith, Peter; Batzer, Mark A.; Walker, Jerilyn A.; Konkel, Miriam K.; Harris, Robert S.; Whittington, Camilla M.; Wong, Emily S. W.; Gemmell, Neil J.; Buschiazzo, Emmanuel; Vargas Jentzsch, Iris M.; Merkel, Angelika; Schmitz, Juergen; Zemann, Anja; Churakov, Gennady; Kriegs, Jan Ole; Brosius, Juergen; Murchison, Elizabeth P.; Sachidanandam, Ravi; Smith, Carly; Hannon, Gregory J.; Tsend-Ayush, Enkhjargal; McMillan, Daniel; Attenborough, Rosalind; Rens, Willem; Ferguson-Smith, Malcolm; Lefèvre, Christophe M.; Sharp, Julie A.; Nicholas, Kevin R.; Ray, David A.; Kube, Michael; Reinhardt, Richard; Pringle, Thomas H.; Taylor, James; Jones, Russell C.; Nixon, Brett; Dacheux, Jean-Louis; Niwa, Hitoshi; Sekita, Yoko; Huang, Xiaoqiu; Stark, Alexander; Kheradpour, Pouya; Kellis, Manolis; Flicek, Paul; Chen, Yuan; Webber, Caleb; Hardison, Ross; Nelson, Joanne; Hallsworth-Pepin, Kym; Delehaunty, Kim; Markovic, Chris; Minx, Pat; Feng, Yucheng; Kremitzki, Colin; Mitreva, Makedonka; Glasscock, Jarret; Wylie, Todd; Wohldmann, Patricia; Thiru, Prathapan; Nhan, Michael N.; Pohl, Craig S.; Smith, Scott M.; Hou, Shunfeng; Renfree, Marilyn B.; Mardis, Elaine R.; Wilson, Richard K.

    2009-01-01

    We present a draft genome sequence of the platypus, Ornithorhynchus anatinus. This monotreme exhibits a fascinating combination of reptilian and mammalian characters. For example, platypuses have a coat of fur adapted to an aquatic lifestyle; platypus females lactate, yet lay eggs; and males are equipped with venom similar to that of reptiles. Analysis of the first monotreme genome aligned these features with genetic innovations. We find that reptile and platypus venom proteins have been co-opted independently from the same gene families; milk protein genes are conserved despite platypuses laying eggs; and immune gene family expansions are directly related to platypus biology. Expansions of protein, non-protein-coding RNA and microRNA families, as well as repeat elements, are identified. Sequencing of this genome now provides a valuable resource for deep mammalian comparative analyses, as well as for monotreme biology and conservation. PMID:18464734

  17. Phlebotomine sandflies of Kenya (Diptera: Psychodidae). I. The validity of Phlebotomus (Larroussius) elgonensis Ngoka, Madel and Mutinga.

    Science.gov (United States)

    Killick-Kendrick, R; Killick-Kendrick, M; Tang, Y; Sang, D K; Johnson, R N; Ngumbi, P M

    1993-04-01

    Sandflies collected in Kitum cave on the Kenyan side of Mount Elgon were identified as Phlebotomus (Larroussius) elgonensis Ngoka, Madel and Mutinga, a species synonymized with P. (L.) aculeatus Lewis, Minter and Ashford, by D. J. Lewis. A comparison of the flies from Kitum cave with P. aculeatus from Lake Elmentaita, Kenya, shows marked differences in the lengths of: (a) the spermathecal ducts of the female; (b) the style, coxite, genital pump and aedeagus of the male; and (c) the palpal segments of both sexes. Other notable differences are in the shape of the base of the spermathecal ducts; the position of spines on, and the shape of, the tip of the aedeagus; and the appearance of the pharyngeal armatures of both sexes. Phlebotomus elgonensis is redescribed and it is concluded that it is sufficiently different from P. aculeatus to deserve recognition as a valid species.

  18. New species from family Gasterosteidae in ichthyofauna of the Caspian Sea basin

    Directory of Open Access Journals (Sweden)

    M. M. Shikhshabekov

    2007-01-01

    Full Text Available There is described a new genus and species - Gasterosteus Aculeatus for the Dagestan part of the Middle Caspian from the genus Gasterosteus species Aculeatus, which differs from other kinds of family Gasterosteidae by presence of three needles on the back part of the body and by some ecological features. This species is well enough described in other southern reservoirs. In comparison of external attributes of the three-needle stickle-back of the Caspian and other southern reservoirs no special differences are revealed.

  19. Comparative aspects of the inner root sheath in adult and developing hairs of mammals in relation to the evolution of hairs.

    Science.gov (United States)

    Alibardi, Lorenzo

    2004-09-01

    The inner root sheath (IRS) allows the exit of hairs through the epidermal surface. The fine structure of monotreme and marsupial IRS and trichohyalin is not known. Using electron microscopy and immunocytochemistry, the localization of trichohyalin and transglutaminase have been studied in monotreme and marsupial hairs, and compared with trichohyalin localization in placental hairs. Trichohyalin in all mammalian species studied here is recognized by a polyclonal antibody against sheep trichohyalin. This generalized immunoreactivity suggests that common epitopes are present in trichohyalin across mammals. In differentiating IRS cells, trichohyalin granules of variable dimensions are composed of an immunolabelled amorphous matrix associated with a network of 10-12-nm-thick keratin filaments. Transglutaminase labelling is present among keratin bundles and trichohyalin granules, and in condensed nuclei of terminally differentiating cells of the inner root sheath. The IRS in monotreme hairs is multistratified but lacks a distinguishable Henle layer. Cornification of IRS determines the sculpturing of the fibre cuticle and later shedding from the follicle for the exit of the hair fibre on the epidermal surface. It is hypothesized that the stratification of IRS in Henle, Huxley and IRS cuticle layers is derived from a simpler organization, like that present in the IRS of monotremes. The IRS is regarded as a localized shedding/sloughing layer needed for the exit of hairs without injury to the epidermis. The formation of the IRS during the evolution of mammalian epidermis allowed the physiological exit of hairs produced inside the skin. The peculiar morphogenesis of hairs in possible primitive skins, such as those of the monotremes (mammals with some reptilian characteristics) or the tails of some rodents (a scaled skin), may elucidate the evolution of hairs. In monotreme and rodent tail skin, the dermal papilla remains localized on the proximal side of the hair peg and

  20. Correlates of red throat coloration in female stickleback and their potential evolutionary significance

    NARCIS (Netherlands)

    Yong, Lengxob; Guo, Ruqing; Wright, Daniel S.; Mears, Samantha A.; Pierotti, Michele; McKinnon, Jeffrey S.

    2013-01-01

    Background: In two stream-resident populations of threespine stickleback (Gasterosteus aculeatus), females often exhibit male-typical red throat coloration. These fish inhabit the Little Campbell River (British Columbia) and Matadero Creek (California). An anadromous population that lacks such color

  1. Male red throat coloration, pelvic spine coloration, and courtship behaviours in threespine stickleback

    NARCIS (Netherlands)

    Wright, Daniel Shane; Yong, Lengxob; Pierotti, Michele E. R.; McKinnon, Jeffrey S.

    2016-01-01

    Background: In addition to exhibiting red nuptial throat coloration, male threespine sticklebacks (Gasterosteus aculeatus) often possess red coloration on their pelvic spines. Although variation in throat colour has been shown to be associated with male reproductive behaviour, limited research has b

  2. Stickleback increase in the Baltic Sea : A thorny issue for coastal predatory fish

    NARCIS (Netherlands)

    Bergstrom, Ulf; Olsson, Jens; Casini, Michele; Eriksson, Britas Klemens; Fredriksson, Ronny; Wennhage, Hakan; Appelberg, Magnus

    2015-01-01

    In the Baltic Sea, the mesopredator three-spined stickleback (Gasterosteus aculeatus) spends a large part of its life cycle in the open sea, but reproduces in shallow coastal habitats. In coastal waters, it may occur in high abundances, is a potent predator on eggs and larvae of fish, and has been s

  3. Correlates of red throat coloration in female stickleback and their potential evolutionary significance

    NARCIS (Netherlands)

    Yong, Lengxob; Guo, Ruqing; Wright, Daniel S.; Mears, Samantha A.; Pierotti, Michele; McKinnon, Jeffrey S.

    2013-01-01

    Background: In two stream-resident populations of threespine stickleback (Gasterosteus aculeatus), females often exhibit male-typical red throat coloration. These fish inhabit the Little Campbell River (British Columbia) and Matadero Creek (California). An anadromous population that lacks such color

  4. Male red throat coloration, pelvic spine coloration, and courtship behaviours in threespine stickleback

    NARCIS (Netherlands)

    Wright, Daniel Shane; Yong, Lengxob; Pierotti, Michele E. R.; McKinnon, Jeffrey S.

    2016-01-01

    Background: In addition to exhibiting red nuptial throat coloration, male threespine sticklebacks (Gasterosteus aculeatus) often possess red coloration on their pelvic spines. Although variation in throat colour has been shown to be associated with male reproductive behaviour, limited research has b

  5. Description of a cellulose-binding domain and a linker sequence from Aspergillus fungi

    NARCIS (Netherlands)

    Quentin, M; Ebbelaar, M; Derksen, J; Mariani, C; van der Valk, H

    A family I cellulose-binding domain (CBD) and a serine- and threonine-rich linker peptide were cloned from the fungi Aspergillus japonicus and Aspergillus aculeatus. A glutathione S-transferase (GST) fusion protein comprising GST and a peptide linker with the CBD fused to its C-terminus, was

  6. Effect of Temperature and High Pressure on the Activity and Mode of Action of Fungal Pectin Methyl Esterase

    NARCIS (Netherlands)

    Duvetter, T.; Fraeye, I.; Sila, D.N.; Verlent, I.; Smout, C.; Clynen, E.; Schoofs, L.; Schols, H.A.; Hendrickx, M.; Loey, van A.

    2006-01-01

    Pectin was de-esterified with purified recombinant Aspergillus aculeatus pectin methyl esterase (PME) during isothermal-isobaric treatments. By measuring the release of methanol as a function of treatment time, the rate of enzymatic pectin conversion was determined. Elevated temperature and pressure

  7. Australian water mites of the subfamily Notoaturinae Besch (Acari: Hydrachnidia: Aturidae), with the description of 24 new species

    NARCIS (Netherlands)

    H. Smit

    2010-01-01

    New data are presented on the subfamily Notoaturinae from Australia. Twenty-four new species are described: Austraturus aculeatus n. sp., A. canaliculatus n. sp., A. lamingtonensis n. sp., A. longigenitalis n. sp., A. montanus n. sp., A. otwayensis n. sp., A. tasmanicus n. sp., Azugaturus gibberipal

  8. Australian water mites of the subfamily Notoaturinae Besch (Acari: Hydrachnidia: Aturidae), with the description of 24 new species

    NARCIS (Netherlands)

    Smit, H.

    2010-01-01

    New data are presented on the subfamily Notoaturinae from Australia. Twenty-four new species are described: Austraturus aculeatus n. sp., A. canaliculatus n. sp., A. lamingtonensis n. sp., A. longigenitalis n. sp., A. montanus n. sp., A. otwayensis n. sp., A. tasmanicus n. sp., Azugaturus

  9. Production of bioavailable flavonoid glucosides in fruit juices and green tea by use of fungal a-L-rhamnosidases

    NARCIS (Netherlands)

    Gonzalez-Barrio, R.; Trindade, L.M.; Manzanares, P.; Graaff, de L.H.; Tomas-Barberan, F.A.; Espin, J.C.

    2004-01-01

    Flavonoid glucosides have been reported to be more bioavailable than their rutinoside counterparts. The aim of this study is to describe a first step in the use of alpha-L-rhamnosidases (RhaA and RhaB) from Aspergillus aculeatus as a way to produce functional beverages based on their potentially inc

  10. [Evolution of genomic imprinting in mammals: what a zoo!].

    Science.gov (United States)

    Proudhon, Charlotte; Bourc'his, Déborah

    2010-05-01

    Genomic imprinting imposes an obligate mode of biparental reproduction in mammals. This phenomenon results from the monoparental expression of a subset of genes. This specific gene regulation mechanism affects viviparous mammals, especially eutherians, but also marsupials to a lesser extent. Oviparous mammals, or monotremes, do not seem to demonstrate monoparental allele expression. This phylogenic confinement suggests that the evolution of the placenta imposed a selective pressure for the emergence of genomic imprinting. This physiological argument is now complemented by recent genomic evidence facilitated by the sequencing of the platypus genome, a rare modern day case of a monotreme. Analysis of the platypus genome in comparison to eutherian genomes shows a chronological and functional coincidence between the appearance of genomic imprinting and transposable element accumulation. The systematic comparative analyses of genomic sequences in different species is essential for the further understanding of genomic imprinting emergence and divergent evolution along mammalian speciation.

  11. The evolution of gene expression levels in mammalian organs

    DEFF Research Database (Denmark)

    Brawand, David; Soumillon, Magali; Necsulea, Anamaria

    2011-01-01

    and chromosomes, owing to differences in selective pressures: transcriptome change was slow in nervous tissues and rapid in testes, slower in rodents than in apes and monotremes, and rapid for the X chromosome right after its formation. Although gene expression evolution in mammals was strongly shaped......Changes in gene expression are thought to underlie many of the phenotypic differences between species. However, large-scale analyses of gene expression evolution were until recently prevented by technological limitations. Here we report the sequencing of polyadenylated RNA from six organs across...... ten species that represent all major mammalian lineages (placentals, marsupials and monotremes) and birds (the evolutionary outgroup), with the goal of understanding the dynamics of mammalian transcriptome evolution. We show that the rate of gene expression evolution varies among organs, lineages...

  12. Comparative cranial morphology in living and extinct platypuses: Feeding behavior, electroreception, and loss of teeth.

    Science.gov (United States)

    Asahara, Masakazu; Koizumi, Masahiro; Macrini, Thomas E; Hand, Suzanne J; Archer, Michael

    2016-10-01

    The modern platypus, Ornithorhynchus anatinus, has an eye structure similar to aquatic mammals; however, platypuses also have a "sixth sense" associated with the bill electro- and mechanoreception that they use without opening their eyes underwater. We hypothesize that Ornithorhynchus and the Miocene taxon Obdurodon have different sensory capacities, which may have resulted from differences in foraging behavior. To estimate differences in foraging, sensory systems, and anatomical divergence between these monotremes, we compared their skull morphologies. Results indicate that the bill of Obdurodon is more dorsally deflected than that of Ornithorhynchus, suggesting a pelagic foraging behavior in Obdurodon compared to the bottom-feeding behavior in Ornithorhynchus. The infraorbital foramen of Obdurodon, through which the maxillary nerve passes sensory data from the bill to the brain, is relatively less developed than that of Ornithorhynchus. Whereas bill-focused sensory perception was likely shared among Mesozoic monotremes, the highly developed electrosensory system of Ornithorhynchus may represent an adaptation to foraging in cloudy water. Computed tomography imagery indicates that the enlarged infraorbital canal of Ornithorhynchus restricts the space available for maxillary tooth roots. Hence, loss of functional teeth in Ornithorhynchus may possibly have resulted from a shift in foraging behavior and coordinate elaboration of the electroreceptive sensory system. Well-developed electroreceptivity in monotremes is known at least as far back as the early Cretaceous; however, there are differences in the extent of elaboration of the feature among members of the ornithorhynchid lineage.

  13. Cyto- and chemoarchitecture of the sensory trigeminal nuclei of the echidna, platypus and rat.

    Science.gov (United States)

    Ashwell, Ken W S; Hardman, Craig D; Paxinos, George

    2006-02-01

    We have examined the cyto- and chemoarchitecture of the trigeminal nuclei of two monotremes using Nissl staining, enzyme reactivity for cytochrome oxidase, immunoreactivity for calcium binding proteins and non-phosphorylated neurofilament (SMI-32 antibody) and lectin histochemistry (Griffonia simplicifolia isolectin B4). The principal trigeminal nucleus and the oralis and interpolaris spinal trigeminal nuclei were substantially larger in the platypus than in either the echidna or rat, but the caudalis subnucleus was similar in size in both monotremes and the rat. The numerical density of Nissl stained neurons was higher in the principal, oralis and interpolaris nuclei of the platypus relative to the echidna, but similar to that in the rat. Neuropil immunoreactivity for parvalbumin was particularly intense in the principal trigeminal, oralis and interpolaris subnuclei of the platypus, but the numerical density of parvalbumin immunoreactive neurons was not particularly high in these nuclei of the platypus. Neuropil immunoreactivity for calbindin and calretinin was relatively weak in both monotremes, although calretinin immunoreactive somata made up a large proportion of neurons in the principal, oralis and interpolaris subnuclei of the echidna. Distribution of calretinin immunoreactivity and Griffonia simplicifolia B4 isolectin reactivity suggested that the caudalis subnucleus of the echidna does not have a clearly defined gelatinosus region. Our findings indicate that the trigeminal nuclei of the echidna do not appear to be highly specialized, but that the principal, oralis and interpolaris subnuclei of the platypus trigeminal complex are highly differentiated, presumably for processing of tactile and electrosensory information from the bill.

  14. Dicty_cDB: Contig-U16002-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available Dictyostelium discoideum cDNA clone:dds19d18, 5' ... 38 3.3 2 ( DB916077 ) Idiosepius paradoxus cDNA, clone:..., 5' e... 46 3.6 2 ( EL906265 ) INIT2_11_B01.b1_A006 G5 trophont cDNA (INIT2) Ich... 46 3.6 2 ( DB916080 ) Idiosepius...tage Plasmodi... 42 4.3 3 ( EK576016 ) 1095521191381 Global-Ocean-Sampling_GS-32-01-01-1... 32 4.3 2 ( DB916246 ) Idiosepius...aculeatus ... 46 6.6 1 ( DN720777 ) CNB135-F10.x1d-t SHGC-CNB Gasterosteus aculeatus ... 46 6.6 1 ( DB915443 ) Idiosepius

  15. Dicty_cDB: Contig-U15022-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 19_pDNRf_477214 Myzus persicae, line G... 56 1e-09 3 ( ES502028 ) BIG_AF_9845 Brine Shrimp diapaused embryos... (cysts... 64 3e-07 2 ( ES496160 ) BIG_AF_3976 Brine Shrimp Adult (20 days after ...hat... 64 4e-07 2 ( DT970853 ) CLJ130-H08.x1d-t SHGC-CLJ Gasterosteus aculeatus ... 64 9e-07 2 ( ES501542 ) BIG_AF_9359 Brine...ES512299 ) BIG_AF_20116 Brine Shrimp embryos, 10 hours after... 64 2e-05 1 ( BC133187 ) Xenopus laevis cDNA ...enopus laevis ... 48 2e-06 3 ( DT990548 ) CLJ250-C10.x1d-t SHGC-CLJ Gasterosteus aculeatus ... 56 5e-06 3 (

  16. Phlebotomine sandflies of Kenya (Diptera: Psychodidae). IV. The armature in the genital atrium of female Larroussius as a means of identification.

    Science.gov (United States)

    Killick-Kendrick, R; Tang, Y; Killick-Kendrick, M

    1994-08-01

    Descriptions are given of armatures in the genital atria of the six known Kenyan species of phlebotomine sandflies of the subgenus, Larroussius, namely Phlebotomus aculeatus, P. elgonensis, P. guggisbergi, P. longipes, P. orientalis and P. pedifer. Phlebotomus aculeatus, P. longipes and P. pedifer can be recognized by the shapes of their armatures. Differences in the length and arrangement of the spines in the armature of P. elgonensis and P. longipes are diagnostic features. The distinguishing feature of P. guggisbergi is a wide variation in spine thickness. The most notable feature of P. orientalis is the angle at which the spines lie. The appearance of the base of the spermathecal duct remains the method of choice for the identification of all six but, if this feature is not well displayed in dissected females, they can be distinguished by the armature. It is suggested that descriptions of new species should include an illustration of the armature in the genital atrium.

  17. Aspergillus saccharolyticus sp. nov., a new black Aspergillus species isolated in Denmark

    DEFF Research Database (Denmark)

    Sørensen, Annette; Lübeck, Peter S.; Lübeck, Mette

    2011-01-01

    A novel species, Aspergillus saccharolyticus sp. nov., belonging to the Aspergillus section Nigri group is described. This species was isolated in Denmark from treated hardwood. Its taxonomic status was determined using a polyphasic taxonomic approach including phenotypic (morphology and extrolite...... Aspergillus species that is morphologically similar to Aspergillus japonicus and Aspergillus aculeatus, but has a totally different extrolite profile compared to any known Aspergillus species. The type strain of A. saccharolyticus sp. nov. is CBS 127449T ( = IBT 28509T)....

  18. Underwater bipedal locomotion by octopuses in disguise.

    Science.gov (United States)

    Huffard, Christine L; Boneka, Farnis; Full, Robert J

    2005-03-25

    Here we report bipedal movement with a hydrostatic skeleton. Two species of octopus walk on two alternating arms using a rolling gait and appear to use the remaining six arms for camouflage. Octopus marginatus resembles a coconut, and Octopus (Abdopus) aculeatus, a clump of floating algae. Using underwater video, we analyzed the kinematics of their strides. Each arm was on the sand for more than half of the stride, qualifying this behavior as a form of walking.

  19. Aspergillus saccharolyticus sp. nov., a new black Aspergillus species isolated in Denmark

    DEFF Research Database (Denmark)

    Sørensen, Annette; Lübeck, Peter S.; Lübeck, Mette

    2011-01-01

    A novel species, Aspergillus saccharolyticus sp. nov., belonging to the Aspergillus section Nigri group is described. This species was isolated in Denmark from treated hardwood. Its taxonomic status was determined using a polyphasic taxonomic approach including phenotypic (morphology and extrolite...... Aspergillus species that is morphologically similar to Aspergillus japonicus and Aspergillus aculeatus, but has a totally different extrolite profile compared to any known Aspergillus species. The type strain of A. saccharolyticus sp. nov. is CBS 127449T ( = IBT 28509T)....

  20. The fish sexual development test: an OECD test guideline proposal with possible relevance for environmental risk assessment. Results from the validation programme

    DEFF Research Database (Denmark)

    Holbech, Henrik; Brande-Lavridsen, Nanna; Kinnberg, Karin Lund;

    2010-01-01

    The Fish Sexual Development Test (FSDT) has gone through two validations as an OECD test guideline for the detection of endocrine active chemicals with different modes of action. The validation has been finalized on four species: Zebrafish (Danio rerio), Japanese medaka (Oryzias latipes), three...... spined stickleback (Gasterosteus aculeatus) and fathead minnow (Pimephales promelas) and with four model compounds: the weak estrogens 4-tert Octylphenol and 4-tert pentylphenol, the aromatase inhibitor prochloraz and the androgen dihydrotestosterone. All species were tested in different laboratories...

  1. Morphological Characterization and Topographic Analysis of Multiple Photoreceptor Types in the Retinae of Mesopelagic Hatchetfishes with Tubular Eyes

    OpenAIRE

    Biagioni, Lauren M.; Hunt, David M.; Collin, Shaun P.

    2016-01-01

    Marine hatchetfishes, Argyropelecus spp., are one of the 14 genera of mesopelagic teleosts, which possess tubular eyes. The tubular eyes are positioned dorsally on the head and consist of a main retina, which subtends a large dorsal binocular field, and an accessory retina, which subtends the lateral monocular visual field. The topographic distribution of photoreceptors in the retina of Argyropelecus sladeni, Argyropelecus affinis, and Argyropelecus aculeatus was determined using a random, un...

  2. Time of harvest affects the yield of soluble polysaccharides extracted enzymatically from potato pulp

    DEFF Research Database (Denmark)

    Ravn, Helle Christine; Sørensen, Ole Bandsholm; Meyer, Anne S.

    2015-01-01

    potato polysaccharides applying a recently developed enzymatic process using 1.0% (w/w) [enzyme/substrate (E/S)] pectin lyase from Aspergillus nidulans and 1.0% (w/w) [E/S] polygalacturonase from A. aculeatus at 60 °C, 100 mM citric acid, pH 6.0 for 1 min. Seven samples drawn within the potato starch...

  3. Definition and characterization of enzymes for maximal biocatalytic solubilization of prebiotic polysaccharides from potato pulp

    DEFF Research Database (Denmark)

    Thomassen, Lise Vestergaard; Larsen, Dorte Møller; Mikkelsen, Jørn Dalgaard

    2011-01-01

    of these polysaccharides from the potato pulp. The pH and temperature optima of two selected pectin lyases from Emericella nidulans (formerly known as Aspergillus nidulans) and Aspergillus niger were determined to 8.6 and 4.0, respectively, at ≥100°C within 1min of reaction. The optima for the two selected...... polygalacturonases from E. nidulans and Aspergillus aculeatus were determined to pH 4.4 and 46°C, and pH 3.7 and ≥80°C, respectively. The polygalacturonase from A. aculeatus was 4–42 times more heat-resistant at 50°C than the other enzymes. The difference in pH optima of the pectin lyases and the exceptional thermal....../w) enzyme/substrate (E/S) pectin lyase from E. nidulans and 1% (w/w) E/S polygalacturonase from A. aculeatus at pH 6.0 and 60°C for 1min....

  4. Electroreception in the Guiana dolphin (Sotalia guianensis).

    Science.gov (United States)

    Czech-Damal, Nicole U; Liebschner, Alexander; Miersch, Lars; Klauer, Gertrud; Hanke, Frederike D; Marshall, Christopher; Dehnhardt, Guido; Hanke, Wolf

    2012-02-22

    Passive electroreception is a widespread sense in fishes and amphibians, but in mammals this sensory ability has previously only been shown in monotremes. While the electroreceptors in fish and amphibians evolved from mechanosensory lateral line organs, those of monotremes are based on cutaneous glands innervated by trigeminal nerves. Electroreceptors evolved from other structures or in other taxa were unknown to date. Here we show that the hairless vibrissal crypts on the rostrum of the Guiana dolphin (Sotalia guianensis), structures originally associated with the mammalian whiskers, serve as electroreceptors. Histological investigations revealed that the vibrissal crypts possess a well-innervated ampullary structure reminiscent of ampullary electroreceptors in other species. Psychophysical experiments with a male Guiana dolphin determined a sensory detection threshold for weak electric fields of 4.6 µV cm(-1), which is comparable to the sensitivity of electroreceptors in platypuses. Our results show that electroreceptors can evolve from a mechanosensory organ that nearly all mammals possess and suggest the discovery of this kind of electroreception in more species, especially those with an aquatic or semi-aquatic lifestyle.

  5. Electroreception and electrolocation in platypus.

    Science.gov (United States)

    Scheich, H; Langner, G; Tidemann, C; Coles, R B; Guppy, A

    Electroreceptors with sensitivity in the microvolt range, which mainly function to detect live prey, are well known in phylogenetically old fishes and some amphibians. In African mormyriform and South American gymnotiform fishes this sense has evolved to an active system using an electric organ as a source for impedance measurement of the environment and for communication. Electroreception in higher vertebrates has not previously been reported. Here we establish that the platypus, the Australian nocturnal diving monotreme, can locate and avoid objects on the basis of d.c. fields. High-frequency sensitivity to a.c. could allow the detection of muscle activity of animals, such as crustaceans, which are preyed on by the platypus. Recordings of cortical evoked potentials showed that the bill of the platypus, previously considered to be exclusively mechanoreceptive, is also an electroreceptive organ with behavioural and electrophysiological sensitivity of approximately 50 microV cm-1. Several lines of evidence suggest that electroreception has evolved independently in this monotreme.

  6. Myoglobin of the shark Heterodontus portusjacksoni: isolation and amino acid sequence.

    Science.gov (United States)

    Fisher, W K; Thompson, E O

    1979-06-01

    Myoglobin isolated from red muscle of the shark H. portusjacksoni was purified by ion-exchange chromatography on sulfopropyl-Sephadex and gel-filtration. Amino acid analysis and sequence determination showed 148 amino acid residues. The amino terminal residue is acetylated as shown by mass spectrographic analysis of N-terminal peptides. There is a deletion of four residues at the amino terminal end as well as one residue in the CD interhelical area relative to other myoglobins. The complete amino acid sequence has been determined following digestion with trypsin, chymotrypsin, pepsin and staphylococcal protease. Sequences of the purified peptides were determined by the dansyl-Edman procedure. The amino acid sequence showed approximately 85 differences from mammalian, monotreme and bird myoglobins. The date of divergence of the shark H. portusjacksoni from these other orders was estimated at 450 +/- 16 million years, based on the number of amino acid differences between species and allowing for multiple mutations during the evolutionary period. This estimate agrees well with similar estimates made using alpha- and beta-globin sequences, in contrast to widely differing estimates of dates of divergence for monotremes using the same three globin chains. Compared with myoglobins from species previously studied, there are many more differences in amino acid sequences, and in many positions residues are found that are more characteristic of alpha- and beta-globins, suggesting a conservation of residues over a long period of evolutionary time. There are fewer stabilizing hydrogen bonds and salt-linkages than in other myoglobins.

  7. Role of the epididymis in sperm competition

    Institute of Scientific and Technical Information of China (English)

    Russell C. Jones; Jean-Louis Dacheux; Brett Nixon; Heath W. Ecroyd

    2007-01-01

    Although it is generally understood that the testes recruited kidney ducts for reproductive function during the evolution of vertebrates, little is understood of the biological significance of the adaptation. In the context of the evolution of the mammalian epididymis, this report provides evidence that a major role of the epididymis is to enhance a male's chance of achieving paternity in a competitive mating system. A unique example of sperm cooperation in monotremes is used as evidence that the epididymis produces sperm competition proteins to form groups of 100 sperm into bundles that have a forward motility nearly thrice that of individual spermatozoa. As it required 3-h incubation in vitro under capacitation conditions to release motile sperm from the bundles, it is suggested that the monotremes provide an example of capacitation that is quite different from capacitation in higher mammals. It is Suggested that variation between species in the intensity of sperm competition could explain the variation that occurs between species in the amount of post-testicular sperm maturation and storage in the epididymis, an explanation of why the human epididymis does not play as important a role in reproduction as the epididymis of most mammals.

  8. Evolution of the turtle bauplan: the topological relationship of the scapula relative to the ribcage.

    Science.gov (United States)

    Lyson, Tyler R; Joyce, Walter G

    2012-12-23

    The turtle shell and the relationship of the shoulder girdle inside or 'deep' to the ribcage have puzzled neontologists and developmental biologists for more than a century. Recent developmental and fossil data indicate that the shoulder girdle indeed lies inside the shell, but anterior to the ribcage. Developmental biologists compare this orientation to that found in the model organisms mice and chickens, whose scapula lies laterally on top of the ribcage. We analyse the topological relationship of the shoulder girdle relative to the ribcage within a broader phylogenetic context and determine that the condition found in turtles is also found in amphibians, monotreme mammals and lepidosaurs. A vertical scapula anterior to the thoracic ribcage is therefore inferred to be the basal amniote condition and indicates that the condition found in therian mammals and archosaurs (which includes both developmental model organisms: chickens and mice) is derived and not appropriate for studying the developmental origin of the turtle shell. Instead, among amniotes, either monotreme mammals or lepidosaurs should be used.

  9. Variability and constraint in the mammalian vertebral column.

    Science.gov (United States)

    Asher, R J; Lin, K H; Kardjilov, N; Hautier, L

    2011-05-01

    Patterns of vertebral variation across mammals have seldom been quantified, making it difficult to test hypotheses of covariation within the axial skeleton and mechanisms behind the high level of vertebral conservatism among mammals. We examined variation in vertebral counts within 42 species of mammals, representing monotremes, marsupials and major clades of placentals. These data show that xenarthrans and afrotherians have, on average, a high proportion of individuals with meristic deviations from species' median series counts. Monotremes, xenarthrans, afrotherians and primates show relatively high variation in thoracolumbar vertebral count. Among the clades sampled in our dataset, rodents are the least variable, with several species not showing any deviations from median vertebral counts, or vertebral anomalies such as asymmetric ribs or transitional vertebrae. Most mammals show significant correlations between sacral position and length of the rib cage; only a few show a correlation between sacral position and number of sternebrae. The former result is consistent with the hypothesis that adult axial skeletal structures patterned by distinct mesodermal tissues are modular and covary; the latter is not. Variable levels of correlation among these structures may indicate that the boundaries of prim/abaxial mesodermal precursors of the axial skeleton are not uniform across species. We do not find evidence for a higher frequency of vertebral anomalies in our sample of embryos or neonates than in post-natal individuals of any species, contrary to the hypothesis that stabilizing selection plays a major role in vertebral patterning.

  10. Mammalian development does not recapitulate suspected key transformations in the evolutionary detachment of the mammalian middle ear.

    Science.gov (United States)

    Ramírez-Chaves, Héctor E; Wroe, Stephen W; Selwood, Lynne; Hinds, Lyn A; Leigh, Chris; Koyabu, Daisuke; Kardjilov, Nikolay; Weisbecker, Vera

    2016-01-13

    The ectotympanic, malleus and incus of the developing mammalian middle ear (ME) are initially attached to the dentary via Meckel's cartilage, betraying their origins from the primary jaw joint of land vertebrates. This recapitulation has prompted mostly unquantified suggestions that several suspected--but similarly unquantified--key evolutionary transformations leading to the mammalian ME are recapitulated in development, through negative allometry and posterior/medial displacement of ME bones relative to the jaw joint. Here we show, using µCT reconstructions, that neither allometric nor topological change is quantifiable in the pre-detachment ME development of six marsupials and two monotremes. Also, differential ME positioning in the two monotreme species is not recapitulated. This challenges the developmental prerequisites of widely cited evolutionary scenarios of definitive mammalian middle ear (DMME) evolution, highlighting the requirement for further fossil evidence to test these hypotheses. Possible association between rear molar eruption, full ME ossification and ME detachment in marsupials suggests functional divergence between dentary and ME as a trigger for developmental, and possibly also evolutionary, ME detachment. The stable positioning of the dentary and ME supports suggestions that a 'partial mammalian middle ear' as found in many mammaliaforms--probably with a cartilaginous Meckel's cartilage--represents the only developmentally plausible evolutionary DMME precursor.

  11. Toward conservation of genetic and phenotypic diversity in Japanese sticklebacks.

    Science.gov (United States)

    Kitano, Jun; Mori, Seiichi

    2016-10-13

    Stickleback fishes have been established as a leading model system for studying the genetic mechanisms that underlie naturally occurring phenotypic diversification. Because of the tremendous diversification achieved by stickleback species in various environments, different geographical populations have unique phenotypes and genotypes, which provide us with unique opportunities for evolutionary genetic research. Among sticklebacks, Japanese species have several unique characteristics that have not been found in other populations. The sympatric marine threespine stickleback species Gasterosteus aculeatus and G. nipponicus (Japan Sea stickleback) are a good system for speciation research. Gasterosteus nipponicus also has several unique characteristics, such as neo-sex chromosomes and courtship behaviors, that differ from those of G. aculeatus. Several freshwater populations derived from G. aculeatus (Hariyo threespine stickleback) inhabit spring-fed ponds and streams in central Honshu and exhibit year-round reproduction, which has never been observed in other stickleback populations. Four species of ninespine stickleback, including Pungitius tymensis and the freshwater, brackish water and Omono types of the P. pungitius-P. sinensis complex, are also excellent model systems for speciation research. Anthropogenic alteration of environments, however, has exposed several Japanese stickleback populations to the risk of extinction and has actually led to extinction of several populations and species. Pungitius kaibarae, which is endemic to East Asia, used to inhabit Kyoto and Hyogo prefectures, but is now extinct. Causes of extinction include depletion of spring water, landfill of habitats, and construction of river-mouth weirs. Here, we review the importance of Japanese sticklebacks as genetic resources, the status of several endangered stickleback populations and species, and the factors putting these populations at risk.

  12. Biomolecular proteomics discloses ATP synthase as the main target of the natural glycoside deglucoruscin.

    Science.gov (United States)

    Del Gaudio, Federica; Festa, Carmen; Mozzicafreddo, Matteo; Vasaturo, Michele; Casapullo, Agostino; De Marino, Simona; Riccio, Raffaele; Monti, Maria Chiara

    2016-10-20

    Extracts of Ruscus aculeatus are a rich source of bioactive steroidal glycosides, such as ruscogenins which are reported to act against chronic venous disorders. Nowadays, several preparations of its roots, commonly used in traditional medicine, are on the market as food supplements for health care and maintenance. Although spirostanol deglucoruscin is one of the main metabolites in these extracts, literature reports about its pharmacological profile are scarce. In this paper, a multi-disciplinary approach, based on chemical proteomics, molecular modelling and bio-organic assays, has been used to disclose the whole interactome of deglucoruscin and the F0-F1 ATP synthase complex has been found as its main target.

  13. Estatus actual de conservación de seis especies de peces dulceacuícolas de la península de Baja California, México

    OpenAIRE

    Gorgonio Ruiz-Campos; Faustino Camarena-Rosales; Adrián F. González-Acosta; Alejandro M. Maeda-Martínez; García de León, Francisco J.; Alejandro Varela-Romero; Asunción Andreu-Soler

    2014-01-01

    Se determinó el estatus actual de conservación de 6 peces dulceacuícolas nativos de la península de Baja California ( Entosphenus tridentatus , Oncorhynchus mykiss nelsoni , Fundulus lima , Cyprinodon macularius , Gasterosteus aculeatus y Gobiesox juniperoserrai ), incluidos en la Norma Oficial Mexicana 059-2010, a partir de la información obtenida durante el periodo 2000-2014. Con excepción de E. tridentatus en la cuenca del río Santo Domingo y de G. juniperoserrai en la cuenca de Las Pocita...

  14. Dicty_cDB: Contig-U12531-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available SHGC-CLJ Gasterosteus aculeatus ... 48 0.77 1 ( EY497720 ) CBBP3718.rev CBBP Hirudo medicinalis hermaphrodi...t... 48 0.77 1 ( EY496316 ) CBBP2847.fwd CBBP Hirudo medicinalis hermaphrodit... 48 0.77 1 ( EY496315 ) CBBP2847.rev CBBP Hirudo medi...cinalis hermaphrodit... 48 0.77 1 ( EY484422 ) CBBP13571.fwd CBBP Hirudo medicina...lis hermaphrodi... 48 0.77 1 ( EY484421 ) CBBP13571.rev CBBP Hirudo medicinalis her...maphrodi... 48 0.77 1 ( EY483641 ) CBBP13100.fwd CBBP Hirudo medicinalis hermaphrodi... 48 0.77 1 ( EY483640

  15. Observations on the flight pattern of some Phlaeothripidae (Thysanoptera species by using suction trap in Hungary

    Directory of Open Access Journals (Sweden)

    Orosz Szilvia

    2016-12-01

    Full Text Available In this study, the seasonal flight activity of the Phlaeothripidae (Thysanoptera species was studied by using suction trap, in South-East Hungary, in the years 2000 and 2004 from April to October. The flight period of two dominant species, namely Haplothrips angusticornis Priesner and Haplothrips aculeatus Fabricius (Thysanoptera: Phlaeothripidae, was observed in high number in Europe. Also, it was the first record of mass flight observation of H. angusticornis. In addition, the effect of meteorological factors, such as temperature, sunshine duration, relative humidity, air pressure, and their influences, were evaluated.

  16. Enzymatic solubilisation and degradation of soybean fibre demonstrated by viscosity, fibre analysis and microscopy

    DEFF Research Database (Denmark)

    Ravn, Jonas Laukkonen; Martens, Helle Juel; Pettersson, Dan

    2015-01-01

    The effect of a commercial multienzyme product obtained by fermentation from Aspergillus aculeatus on soybean and soybean meal was investigated using viscosity measurements, dietary fibre component analysis and different microscopy techniques utilizing histochemical dyes and antibody labelling...... and hemicellulose components of soybean cell wall were also used to visualize several enzyme activities in the commercial enzyme preparation The challenges of using commercial antibodies elicited from a given plant source to detect similar epitiopes on another plant source are also discussed. Non...... soybean cell wall components as part of the undesirable antinutrients in animal feed....

  17. Crystal packing in two pH-dependent crystal forms of rhamnogalacturonan acetylesterase

    DEFF Research Database (Denmark)

    Mølgaard, Anne; Larsen, S.

    2004-01-01

    The glycoprotein rhamnogalacturonan acetylesterase from Aspergillus aculeatus has been crystallized in two crystal forms, an orthorhombic and a trigonal crystal form. In the orthorhombic crystal form, the covalently bound carbohydrate at one of the two N-glycosylation sites is involved in crystal...... contacts. The orthorhombic crystal form was obtained at pH 5.0 and the trigonal crystal form at pH 4.5. In one case, the two crystal forms were found in the same drop at pH 4.7. The differences in crystal packing in the two crystal forms can be explained by the pH-dependent variation in the protonation...

  18. Baseline identification in stable -isotope studies of temperate lotic systems and implications for calculated trophic positions

    DEFF Research Database (Denmark)

    Kristensen, Peter Brinkmann; Riis, Tenna; Dylmer, Hans Erik;

    2016-01-01

    of two common fish species (three-spined stickleback, Gasterosteus aculeatus, and brown trout Salmo trutta) differed markedly depending on the baseline chosen. The estimated trophic position was lowest when based on Baetidae and highest when using Simuliidae. The trophic position of Gasterosteus...... in the catchment and had a slope deviating from zero for both fish species, despite gut content analysis revealed no such trophic level dependency of land use. This suggests that Baetidae are not good baseline indicators of trophic position, perhaps because their main food item (periphyton) may include nitrogen...

  19. Predation vulnerability of planktonic copepods: consequences of predator foraging strategies and prey sensory abilities

    DEFF Research Database (Denmark)

    Viitasalo, M; Kiørboe, T; Flinkman, J.;

    1998-01-01

    We investigated the vulnerability of 2 copepod species (Eurytemora affinis and Temora longicornis) to predation by predators with different foraging modes, three-spined stickleback Gasterosteus aculeatus juveniles and mysid shrimps Neomysis integer. Copepods were videofilmed escaping from predators...... of the sticklebacks was higher than that of mysids. In the case of sticklebacks foraging on E. affinis, copepod reaction distance was significantly correlated with stickleback approaching speed; sticklebacks captured a copepod only if they were able to slowly approach to within a strike distance of...

  20. Imaging of Bacterial and Fungal Cells Using Fluorescent Carbon Dots Prepared from Carica papaya Juice.

    Science.gov (United States)

    Kasibabu, Betha Saineelima B; D'souza, Stephanie L; Jha, Sanjay; Kailasa, Suresh Kumar

    2015-07-01

    In this paper, we have described a simple hydrothermal method for preparation of fluorescent carbon dots (C-dots) using Carica papaya juice as a precursor. The synthesized C-dots show emission peak at 461 nm with a quantum yield of 7.0 %. The biocompatible nature of C-dots was confirmed by a cytotoxicity assay on E. coli. The C-dots were used as fluorescent probes for imaging of bacterial (Bacillus subtilis) and fungal (Aspergillus aculeatus) cells and emitted green and red colors under different excitation wavelengths, which indicates that the C-dots can be used as a promising material for cell imaging.

  1. Dicty_cDB: Contig-U05475-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available . 46 1.3 1 ( DY594159 ) KIDNEYF042327N20 POSSUM_01-POSSUM-KIDNEY-2KB Tric... 46 1.3 1 ( DB871834 ) Lipochromis sp. 'matumbi hunter...' cDNA clone:hm764... 46 1.3 1 ( DB870676 ) Lipochromis sp. 'matumbi hunter...' cDNA clone:hm750... 46 1.3 1 ( DB864953 ) Lipochromis sp. 'matumbi hunter' cDNA clone:hm78..... 44 5.3 1 ( DN683050 ) CGX27-G02.x1d-t SHGC-CGX Gasterosteus aculeatus c... 44 5.3 1 ( DB874016 ) Lipochromis sp. 'matumbi hunter

  2. Five new Talaromyces species with ampulliform-like phialides and globose rough walled conidia resembling T. verruculosus

    DEFF Research Database (Denmark)

    Visagie, Cobus M.; Yilmaz, Neriman; Frisvad, Jens Christian

    2015-01-01

    Talaromyces verruculosus, T. aculeatus and T. apiculatus are the only Talaromyces species that produce conidiophores with ampulliform phialides, which taper into very thin necks and have rough walled, globose conidia. In this study, we introduce five new species with similar micromorphological...... to grow on CYA at 37 °C. Talaromyces veerkampii (CBS 500.78T) grows rapidly on MEA (38–42 mm) and colonies on YES has a bronze green reverse. Talaromyces fuscoviridis (CBS 193.69T) colonies have dark green reverses on MEA and commonly produces red exudates on other media. Talaromyces stellenboschiensis...

  3. The lamina cribrosa of Ornithorhynchus (Monotremata, Mammalia).

    Science.gov (United States)

    Zeller, U

    1988-01-01

    A vestigial and transitory lamina cribrosa was found in nestling platypus (Ornithorhynchus anatinus). The heads of two nest-young (180 and 333 mm length), one subadult and one adult Ornithorhynchus were serially sectioned and studied with special reference to the development of the nasal region. In nest-young Ornithorhynchus an irregularly shaped bar of cartilage develops at the foramen olfactorium advehens. In the subadult it is largely resorbed, and in the osseous skull of the adult it is completely lacking. Ontogeny and topographical relationships of this bar of cartilage indicate that it is part of a lamina cribrosa. It embraces the ramus medialis of the nervus ethmoidalis and the arteria ethmoidalis, as do the corresponding parts of the lamina cribrosa of Tachyglossus. Compared to other parts of the chondrocranium this bar develops late in ontogeny, as does the lamina cribrosa of other mammals. Therefore, it can be concluded that part of the lamina cribrosa is present for a short period during the ontogeny of Ornithorhynchus, contrary to earlier reports. As in many other water-adapted mammals, the olfactory system of Ornithorhynchus is reduced. This suggests that the rest of the lamina cribrosa of Ornithorhynchus is secondarily reduced. The common ancestor of Ornithorhynchus and Tachyglossidae most probably possessed a lamina cribrosa which can be traced back to the common mammalian stock. The lamina cribrosa developed only once in the phylogeny of mammals. Its lack in the adult Ornithorhynchus is not a "reptilian" character.

  4. Sequencing the Black Aspergilli species complex

    Energy Technology Data Exchange (ETDEWEB)

    Kuo, Alan; Salamov, Asaf; Zhou, Kemin; Otillar, Robert; Baker, Scott; Grigoriev, Igor

    2011-03-11

    The ~15 members of the Aspergillus section Nigri species complex (the "Black Aspergilli") are significant as platforms for bioenergy and bioindustrial technology, as members of soil microbial communities and players in the global carbon cycle, and as food processing and spoilage agents and agricultural toxigens. Despite their utility and ubiquity, the morphological and metabolic distinctiveness of the complex's members, and thus their taxonomy, is poorly defined. We are using short read pyrosequencing technology (Roche/454 and Illumina/Solexa) to rapidly scale up genomic and transcriptomic analysis of this species complex. To date we predict 11197 genes in Aspergillus niger, 11624 genes in A. carbonarius, and 10845 genes in A. aculeatus. A. aculeatus is our most recent genome, and was assembled primarily from 454-sequenced reads and annotated with the aid of >2 million 454 ESTs and >300 million Solexa ESTs. To most effectively deploy these very large numbers of ESTs we developed 2 novel methods for clustering the ESTs into assemblies. We have also developed a pipeline to propose orthologies and paralogies among genes in the species complex. In the near future we will apply these methods to additional species of Black Aspergilli that are currently in our sequencing pipeline.

  5. Screening and Identification of Novel Ochratoxin A-Producing Fungi from Grapes

    Directory of Open Access Journals (Sweden)

    Xiaoyun Zhang

    2016-11-01

    Full Text Available Ochratoxin A (OTA contamination has been established as a world-wide problem. In this study, the strains with the ability of OTA production were screened by analyzing the green fluorescence of the isolates colonies from the grapes in Zhenjiang with 365 nm UV light and confirmed by HPLC with fluorescent detection (HPLC-FLD. The results showed that seven isolates acquired the characteristic of the fluorescence, of which only five showed the ability of OTA production as confirmed by HPLC-FLD analysis. The five OTA-producing strains were identified based on comparative sequence analysis of three conserved genes (ITS, BenA and RPB2 of the strains, and they are Talaromyces rugulosus (O1 and Q3, Penicillium commune (V5-1, Penicillium rubens (MQ-5 and Aspergillus aculeatus (MB1-1. There are two Penicillium species of the five OTA-producing strains and our study is the first to report that P. rubens, T. rugulosus and A. aculeatus can produce OTA. This work would contribute to comprehensively understanding the fungi with an OTA-producing ability in grapes before harvest and then take effective measures to prevent OTA production.

  6. Screening and Identification of Novel Ochratoxin A-Producing Fungi from Grapes

    Science.gov (United States)

    Zhang, Xiaoyun; Li, Yulin; Wang, Haiying; Gu, Xiangyu; Zheng, Xiangfeng; Wang, Yun; Diao, Junwei; Peng, Yaping; Zhang, Hongyin

    2016-01-01

    Ochratoxin A (OTA) contamination has been established as a world-wide problem. In this study, the strains with the ability of OTA production were screened by analyzing the green fluorescence of the isolates colonies from the grapes in Zhenjiang with 365 nm UV light and confirmed by HPLC with fluorescent detection (HPLC-FLD). The results showed that seven isolates acquired the characteristic of the fluorescence, of which only five showed the ability of OTA production as confirmed by HPLC-FLD analysis. The five OTA-producing strains were identified based on comparative sequence analysis of three conserved genes (ITS, BenA and RPB2) of the strains, and they are Talaromyces rugulosus (O1 and Q3), Penicillium commune (V5-1), Penicillium rubens (MQ-5) and Aspergillus aculeatus (MB1-1). There are two Penicillium species of the five OTA-producing strains and our study is the first to report that P. rubens, T. rugulosus and A. aculeatus can produce OTA. This work would contribute to comprehensively understanding the fungi with an OTA-producing ability in grapes before harvest and then take effective measures to prevent OTA production. PMID:27845758

  7. The genome sequence of taurine cattle: a window to ruminant biology and evolution.

    Science.gov (United States)

    Elsik, Christine G; Tellam, Ross L; Worley, Kim C; Gibbs, Richard A; Muzny, Donna M; Weinstock, George M; Adelson, David L; Eichler, Evan E; Elnitski, Laura; Guigó, Roderic; Hamernik, Debora L; Kappes, Steve M; Lewin, Harris A; Lynn, David J; Nicholas, Frank W; Reymond, Alexandre; Rijnkels, Monique; Skow, Loren C; Zdobnov, Evgeny M; Schook, Lawrence; Womack, James; Alioto, Tyler; Antonarakis, Stylianos E; Astashyn, Alex; Chapple, Charles E; Chen, Hsiu-Chuan; Chrast, Jacqueline; Câmara, Francisco; Ermolaeva, Olga; Henrichsen, Charlotte N; Hlavina, Wratko; Kapustin, Yuri; Kiryutin, Boris; Kitts, Paul; Kokocinski, Felix; Landrum, Melissa; Maglott, Donna; Pruitt, Kim; Sapojnikov, Victor; Searle, Stephen M; Solovyev, Victor; Souvorov, Alexandre; Ucla, Catherine; Wyss, Carine; Anzola, Juan M; Gerlach, Daniel; Elhaik, Eran; Graur, Dan; Reese, Justin T; Edgar, Robert C; McEwan, John C; Payne, Gemma M; Raison, Joy M; Junier, Thomas; Kriventseva, Evgenia V; Eyras, Eduardo; Plass, Mireya; Donthu, Ravikiran; Larkin, Denis M; Reecy, James; Yang, Mary Q; Chen, Lin; Cheng, Ze; Chitko-McKown, Carol G; Liu, George E; Matukumalli, Lakshmi K; Song, Jiuzhou; Zhu, Bin; Bradley, Daniel G; Brinkman, Fiona S L; Lau, Lilian P L; Whiteside, Matthew D; Walker, Angela; Wheeler, Thomas T; Casey, Theresa; German, J Bruce; Lemay, Danielle G; Maqbool, Nauman J; Molenaar, Adrian J; Seo, Seongwon; Stothard, Paul; Baldwin, Cynthia L; Baxter, Rebecca; Brinkmeyer-Langford, Candice L; Brown, Wendy C; Childers, Christopher P; Connelley, Timothy; Ellis, Shirley A; Fritz, Krista; Glass, Elizabeth J; Herzig, Carolyn T A; Iivanainen, Antti; Lahmers, Kevin K; Bennett, Anna K; Dickens, C Michael; Gilbert, James G R; Hagen, Darren E; Salih, Hanni; Aerts, Jan; Caetano, Alexandre R; Dalrymple, Brian; Garcia, Jose Fernando; Gill, Clare A; Hiendleder, Stefan G; Memili, Erdogan; Spurlock, Diane; Williams, John L; Alexander, Lee; Brownstein, Michael J; Guan, Leluo; Holt, Robert A; Jones, Steven J M; Marra, Marco A; Moore, Richard; Moore, Stephen S; Roberts, Andy; Taniguchi, Masaaki; Waterman, Richard C; Chacko, Joseph; Chandrabose, Mimi M; Cree, Andy; Dao, Marvin Diep; Dinh, Huyen H; Gabisi, Ramatu Ayiesha; Hines, Sandra; Hume, Jennifer; Jhangiani, Shalini N; Joshi, Vandita; Kovar, Christie L; Lewis, Lora R; Liu, Yih-Shin; Lopez, John; Morgan, Margaret B; Nguyen, Ngoc Bich; Okwuonu, Geoffrey O; Ruiz, San Juana; Santibanez, Jireh; Wright, Rita A; Buhay, Christian; Ding, Yan; Dugan-Rocha, Shannon; Herdandez, Judith; Holder, Michael; Sabo, Aniko; Egan, Amy; Goodell, Jason; Wilczek-Boney, Katarzyna; Fowler, Gerald R; Hitchens, Matthew Edward; Lozado, Ryan J; Moen, Charles; Steffen, David; Warren, James T; Zhang, Jingkun; Chiu, Readman; Schein, Jacqueline E; Durbin, K James; Havlak, Paul; Jiang, Huaiyang; Liu, Yue; Qin, Xiang; Ren, Yanru; Shen, Yufeng; Song, Henry; Bell, Stephanie Nicole; Davis, Clay; Johnson, Angela Jolivet; Lee, Sandra; Nazareth, Lynne V; Patel, Bella Mayurkumar; Pu, Ling-Ling; Vattathil, Selina; Williams, Rex Lee; Curry, Stacey; Hamilton, Cerissa; Sodergren, Erica; Wheeler, David A; Barris, Wes; Bennett, Gary L; Eggen, André; Green, Ronnie D; Harhay, Gregory P; Hobbs, Matthew; Jann, Oliver; Keele, John W; Kent, Matthew P; Lien, Sigbjørn; McKay, Stephanie D; McWilliam, Sean; Ratnakumar, Abhirami; Schnabel, Robert D; Smith, Timothy; Snelling, Warren M; Sonstegard, Tad S; Stone, Roger T; Sugimoto, Yoshikazu; Takasuga, Akiko; Taylor, Jeremy F; Van Tassell, Curtis P; Macneil, Michael D; Abatepaulo, Antonio R R; Abbey, Colette A; Ahola, Virpi; Almeida, Iassudara G; Amadio, Ariel F; Anatriello, Elen; Bahadue, Suria M; Biase, Fernando H; Boldt, Clayton R; Carroll, Jeffery A; Carvalho, Wanessa A; Cervelatti, Eliane P; Chacko, Elsa; Chapin, Jennifer E; Cheng, Ye; Choi, Jungwoo; Colley, Adam J; de Campos, Tatiana A; De Donato, Marcos; Santos, Isabel K F de Miranda; de Oliveira, Carlo J F; Deobald, Heather; Devinoy, Eve; Donohue, Kaitlin E; Dovc, Peter; Eberlein, Annett; Fitzsimmons, Carolyn J; Franzin, Alessandra M; Garcia, Gustavo R; Genini, Sem; Gladney, Cody J; Grant, Jason R; Greaser, Marion L; Green, Jonathan A; Hadsell, Darryl L; Hakimov, Hatam A; Halgren, Rob; Harrow, Jennifer L; Hart, Elizabeth A; Hastings, Nicola; Hernandez, Marta; Hu, Zhi-Liang; Ingham, Aaron; Iso-Touru, Terhi; Jamis, Catherine; Jensen, Kirsty; Kapetis, Dimos; Kerr, Tovah; Khalil, Sari S; Khatib, Hasan; Kolbehdari, Davood; Kumar, Charu G; Kumar, Dinesh; Leach, Richard; Lee, Justin C-M; Li, Changxi; Logan, Krystin M; Malinverni, Roberto; Marques, Elisa; Martin, William F; Martins, Natalia F; Maruyama, Sandra R; Mazza, Raffaele; McLean, Kim L; Medrano, Juan F; Moreno, Barbara T; Moré, Daniela D; Muntean, Carl T; Nandakumar, Hari P; Nogueira, Marcelo F G; Olsaker, Ingrid; Pant, Sameer D; Panzitta, Francesca; Pastor, Rosemeire C P; Poli, Mario A; Poslusny, Nathan; Rachagani, Satyanarayana; Ranganathan, Shoba; Razpet, Andrej; Riggs, Penny K; Rincon, Gonzalo; Rodriguez-Osorio, Nelida; Rodriguez-Zas, Sandra L; Romero, Natasha E; Rosenwald, Anne; Sando, Lillian; Schmutz, Sheila M; Shen, Libing; Sherman, Laura; Southey, Bruce R; Lutzow, Ylva Strandberg; Sweedler, Jonathan V; Tammen, Imke; Telugu, Bhanu Prakash V L; Urbanski, Jennifer M; Utsunomiya, Yuri T; Verschoor, Chris P; Waardenberg, Ashley J; Wang, Zhiquan; Ward, Robert; Weikard, Rosemarie; Welsh, Thomas H; White, Stephen N; Wilming, Laurens G; Wunderlich, Kris R; Yang, Jianqi; Zhao, Feng-Qi

    2009-04-24

    To understand the biology and evolution of ruminants, the cattle genome was sequenced to about sevenfold coverage. The cattle genome contains a minimum of 22,000 genes, with a core set of 14,345 orthologs shared among seven mammalian species of which 1217 are absent or undetected in noneutherian (marsupial or monotreme) genomes. Cattle-specific evolutionary breakpoint regions in chromosomes have a higher density of segmental duplications, enrichment of repetitive elements, and species-specific variations in genes associated with lactation and immune responsiveness. Genes involved in metabolism are generally highly conserved, although five metabolic genes are deleted or extensively diverged from their human orthologs. The cattle genome sequence thus provides a resource for understanding mammalian evolution and accelerating livestock genetic improvement for milk and meat production.

  8. Metabolism of dinosaurs as determined from their growth

    Science.gov (United States)

    Lee, Scott A.

    2015-09-01

    A model based on cellular properties is used to analyze the mass growth curves of 20 dinosaurs. This analysis yields the first measurement of the average cellular metabolism of dinosaurs. The organismal metabolism is also determined. The cellular metabolism of dinosaurs is found to decrease with mass at a slower rate than is observed in extant animals. The organismal metabolism increases with the mass of the dinosaur. These results come from both the Saurischia and Ornithischia branches of Dinosauria, suggesting that the observed metabolic features were common to all dinosaurs. The results from dinosaurs are compared to data from extant placental and marsupial mammals, a monotreme, and altricial and precocial birds, reptiles, and fish. Dinosaurs had cellular and organismal metabolisms in the range observed in extant mesotherms.

  9. Sir William Turner and his studies on the mammalian placenta.

    Science.gov (United States)

    Magee, Reginald

    2003-06-01

    William Turner was appointed Professor of Anatomy at the University of Edinburgh in 1867, and from 1903 until his death in 1916, he was Principal and Vice-Chancellor. He was an outstanding teacher and many of those he taught went on to occupy chairs of anatomy. He published widely on anatomical subjects and one of his interests was comparative anatomy and physiology of the placenta. This paper takes a brief look at Turner's studies on the anatomical structure of the placenta, its comparative anatomy, his thoughts about its physiology and its place in the evolutionary process. At the time, these lectures constituted an anatomical and physiological classic. At the time Turner prepared his lectures, which were delivered in 1875 and 1876, little was known about the gestatory process in marsupials or monotremes. These mammals have a very brief period of intrauterine gestation and placentation and mention is made of studies that have been done in recent times on this subject.

  10. New gliding mammaliaforms from the Jurassic

    Science.gov (United States)

    Meng, Qing-Jin; Grossnickle, David M.; Liu, Di; Zhang, Yu-Guang; Neander, April I.; Ji, Qiang; Luo, Zhe-Xi

    2017-08-01

    Stem mammaliaforms are Mesozoic forerunners to mammals, and they offer critical evidence for the anatomical evolution and ecological diversification during the earliest mammalian history. Two new eleutherodonts from the Late Jurassic period have skin membranes and skeletal features that are adapted for gliding. Characteristics of their digits provide evidence of roosting behaviour, as in dermopterans and bats, and their feet have a calcaneal calcar to support the uropagatium as in bats. The new volant taxa are phylogenetically nested with arboreal eleutherodonts. Together, they show an evolutionary experimentation similar to the iterative evolutions of gliders within arboreal groups of marsupial and placental mammals. However, gliding eleutherodonts possess rigid interclavicle-clavicle structures, convergent to the avian furculum, and they retain shoulder girdle plesiomorphies of mammaliaforms and monotremes. Forelimb mobility required by gliding occurs at the acromion-clavicle and glenohumeral joints, is different from and convergent to the shoulder mobility at the pivotal clavicle-sternal joint in marsupial and placental gliders.

  11. Ancient antimicrobial peptides kill antibiotic-resistant pathogens: Australian mammals provide new options.

    Science.gov (United States)

    Wang, Jianghui; Wong, Emily S W; Whitley, Jane C; Li, Jian; Stringer, Jessica M; Short, Kirsty R; Renfree, Marilyn B; Belov, Katherine; Cocks, Benjamin G

    2011-01-01

    To overcome the increasing resistance of pathogens to existing antibiotics the 10×'20 Initiative declared the urgent need for a global commitment to develop 10 new antimicrobial drugs by the year 2020. Naturally occurring animal antibiotics are an obvious place to start. The recently sequenced genomes of mammals that are divergent from human and mouse, including the tammar wallaby and the platypus, provide an opportunity to discover novel antimicrobials. Marsupials and monotremes are ideal potential sources of new antimicrobials because they give birth to underdeveloped immunologically naïve young that develop outside the sterile confines of a uterus in harsh pathogen-laden environments. While their adaptive immune system develops innate immune factors produced either by the mother or by the young must play a key role in protecting the immune-compromised young. In this study we focus on the cathelicidins, a key family of antimicrobial peptide genes. We identified 14 cathelicidin genes in the tammar wallaby genome and 8 in the platypus genome. The tammar genes were expressed in the mammary gland during early lactation before the adaptive immune system of the young develops, as well as in the skin of the pouch young. Both platypus and tammar peptides were effective in killing a broad range of bacterial pathogens. One potent peptide, expressed in the early stages of tammar lactation, effectively killed multidrug-resistant clinical isolates of Pseudomonas aeruginosa, Klebsiella pneumoniae and Acinetobacter baumannii. Marsupial and monotreme young are protected by antimicrobial peptides that are potent, broad spectrum and salt resistant. The genomes of our distant relatives may hold the key for the development of novel drugs to combat multidrug-resistant pathogens.

  12. Definition and characterization of enzymes for maximal biocatalytic solubilization of prebiotic polysaccharides from potato pulp.

    Science.gov (United States)

    Thomassen, Lise V; Larsen, Dorte M; Mikkelsen, Jørn D; Meyer, Anne S

    2011-08-10

    Potato pulp is a high-volume co-processing product resulting from industrial potato starch manufacturing. Potato pulp is particularly rich in pectin, notably galactan branched rhamnogalacturonan I polysaccharides, which are highly bifidogenic when solubilized. The objective of the present study was to characterize and compare four homogalacturonan degrading enzymes capable of catalyzing the required solubilization of these pectinaceous polysaccharides from potato pulp in a 1 min reaction. An additional purpose was to assess the influence of the pH and the potential buffer chelating effects on the release of these polysaccharides from the potato pulp. The pH and temperature optima of two selected pectin lyases from Emericella nidulans (formerly known as Aspergillus nidulans) and Aspergillus niger were determined to 8.6 and 4.0, respectively, at ≥100 °C within 1 min of reaction. The optima for the two selected polygalacturonases from E. nidulans and Aspergillus aculeatus were determined to pH 4.4 and 46 °C, and pH 3.7 and ≥80 °C, respectively. The polygalacturonase from A. aculeatus was 4-42 times more heat-resistant at 50 °C than the other enzymes. The difference in pH optima of the pectin lyases and the exceptional thermal stabilities of some of the enzymes are proposed to be related to specific amino acid substitutions, stabilizing hydrogen bonding and structural traits of the enzymes. The K(M) and V(max) values ranged from 0.3-0.6g/L and 0.5-250.5 U/mg protein, respectively. Phosphate buffer induced release of a higher amount of dry matter than Tris-acetate buffer at pH 6, indicating a chelating effect of the phosphate. Moreover, the phosphate had a higher chelating effect at pH 6 than at pH 4. The optimal conditions for a high yield of polysaccharides from potato pulp were therefore: 1% (w/w) potato pulp treated with 1% (w/w) enzyme/substrate (E/S) pectin lyase from E. nidulans and 1% (w/w) E/S polygalacturonase from A. aculeatus at pH 6.0 and 60 °C for

  13. Mapping present and future potential distribution patterns for a meso-grazer guild in the Baltic Sea.

    Science.gov (United States)

    Leidenberger, Sonja; De Giovanni, Renato; Kulawik, Robert; Williams, Alan R; Bourlat, Sarah J; Maggs, Christine

    2015-02-01

    The Baltic Sea is one of the world's largest semi-enclosed brackish water bodies characterized by many special features, including endemic species that may be particularly threatened by climate change. We mapped potential distribution patterns under present and future conditions for a community with three trophic levels. We analysed climate-induced changes in the species' distribution patterns and examined possible consequences for the chosen food web. Baltic Sea and northern Europe. We developed two open-source workflow-based analytical tools: one for ecological niche modelling and another for raster layer comparison to compute the extent and intensity of change in species' potential distributions. Individual ecological niche models were generated under present conditions and then projected into a future climate change scenario (2050) for a food web consisting of a guild of meso-grazers (Idotea spp.), their host algae (Fucus vesiculosus and Fucus radicans) and their fish predator (Gasterosteus aculeatus). We used occurrence data from the Global Biodiversity Information Facility (GBIF), literature and museum collections, together with five environmental layers at a resolution of 5 and 30 arc-minutes. Habitat suitability for Idotea balthica and Idotea chelipes in the Baltic Sea seems to be mostly determined by temperature and ice cover rather than by salinity. 2050 predictions for all modelled species show a northern/north-eastern shift in the Baltic Sea. The distribution ranges for Idotea granulosa and G. aculeatus are predicted to become patchier in the Baltic than in the rest of northern Europe, where the species will gain more suitable habitats. For the Baltic Sea, climate-induced changes resulted in a gain of suitable habitats for F. vesiculosus,I. chelipes and I. balthica, whereas lower habitat suitability was predicted for I. granulosa,F. radicans and G. aculeatus. The predicted north-eastern shift of I. balthica and I. chelipes into the distribution area of

  14. Mapping present and future potential distribution patterns for a meso-grazer guild in the Baltic Sea

    Science.gov (United States)

    Leidenberger, Sonja; De Giovanni, Renato; Kulawik, Robert; Williams, Alan R; Bourlat, Sarah J; Maggs, Christine

    2015-01-01

    Aim The Baltic Sea is one of the world's largest semi-enclosed brackish water bodies characterized by many special features, including endemic species that may be particularly threatened by climate change. We mapped potential distribution patterns under present and future conditions for a community with three trophic levels. We analysed climate-induced changes in the species' distribution patterns and examined possible consequences for the chosen food web. Location Baltic Sea and northern Europe. Methods We developed two open-source workflow-based analytical tools: one for ecological niche modelling and another for raster layer comparison to compute the extent and intensity of change in species' potential distributions. Individual ecological niche models were generated under present conditions and then projected into a future climate change scenario (2050) for a food web consisting of a guild of meso-grazers (Idotea spp.), their host algae (Fucus vesiculosus and Fucus radicans) and their fish predator (Gasterosteus aculeatus). We used occurrence data from the Global Biodiversity Information Facility (GBIF), literature and museum collections, together with five environmental layers at a resolution of 5 and 30 arc-minutes. Results Habitat suitability for Idotea balthica and Idotea chelipes in the Baltic Sea seems to be mostly determined by temperature and ice cover rather than by salinity. 2050 predictions for all modelled species show a northern/north-eastern shift in the Baltic Sea. The distribution ranges for Idotea granulosa and G. aculeatus are predicted to become patchier in the Baltic than in the rest of northern Europe, where the species will gain more suitable habitats. Main conclusions For the Baltic Sea, climate-induced changes resulted in a gain of suitable habitats for F. vesiculosus,I. chelipes and I. balthica, whereas lower habitat suitability was predicted for I. granulosa,F. radicans and G. aculeatus. The predicted north-eastern shift of I. balthica

  15. Inbreeding avoidance through non-random mating in sticklebacks.

    Science.gov (United States)

    Frommen, Joachim G; Bakker, Theo C M

    2006-06-22

    Negative effects of inbreeding are well documented in a wide range of animal taxa. Hatching success and survival of inbred offspring is reduced in many species and inbred progeny are often less attractive to potential mates. Thus, individuals should avoid mating with close kin. However, experimental evidence for inbreeding avoidance through non-random mating in vertebrates is scarce. Here, we show that gravid female three-spined sticklebacks (Gasterosteus aculeatus) when given the choice between a courting familiar brother and a courting unfamiliar non-sib prefer to mate with the non-sib and thus avoid the disadvantages of incest. We controlled for differences in males' body size and red intensity of nuptial coloration. Thus, females adjust their courting behaviour to the risk of inbreeding.

  16. Bioethanol production from the nutrient stress-induced microalga Chlorella vulgaris by enzymatic hydrolysis and immobilized yeast fermentation.

    Science.gov (United States)

    Kim, Kyoung Hyoun; Choi, In Seong; Kim, Ho Myeong; Wi, Seung Gon; Bae, Hyeun-Jong

    2014-02-01

    The microalga Chlorella vulgaris is a potential feedstock for bioenergy due to its rapid growth, carbon dioxide fixation efficiency, and high accumulation of lipids and carbohydrates. In particular, the carbohydrates in microalgae make them a candidate for bioethanol feedstock. In this study, nutrient stress cultivation was employed to enhance the carbohydrate content of C. vulgaris. Nitrogen limitation increased the carbohydrate content to 22.4% from the normal content of 16.0% on dry weight basis. In addition, several pretreatment methods and enzymes were investigated to increase saccharification yields. Bead-beating pretreatment increased hydrolysis by 25% compared with the processes lacking pretreatment. In the enzymatic hydrolysis process, the pectinase enzyme group was superior for releasing fermentable sugars from carbohydrates in microalgae. In particular, pectinase from Aspergillus aculeatus displayed a 79% saccharification yield after 72h at 50°C. Using continuous immobilized yeast fermentation, microalgal hydrolysate was converted into ethanol at a yield of 89%.

  17. Rhamnogalacturonan lyase reveals a unique three-domain modular structure for polysaccharide lyase family 4

    DEFF Research Database (Denmark)

    McDonough, Michael A.; Kadirvelraj, Renuka; Harris, Pernille

    2004-01-01

    Rhamnogalacturonan lyase (RG-lyase) specifically recognizes and cleaves alpha-1,4 glycosidic bonds between L-rhamnose and D-galacturonic acids in the backbone of rhamno galacturonan-I, a major component of the plant cell wall polysaccharide, pectin. The three-dimensional structure of RG-lyase fro...... structural homology to non-catalytic domains from other carbohydrate active enzymes.......Rhamnogalacturonan lyase (RG-lyase) specifically recognizes and cleaves alpha-1,4 glycosidic bonds between L-rhamnose and D-galacturonic acids in the backbone of rhamno galacturonan-I, a major component of the plant cell wall polysaccharide, pectin. The three-dimensional structure of RG-lyase from...... Aspergillus aculeatus has been determined to 1.5 Angstrom resolution representing the first known structure from polysaccharide lyase family 4 and of an enzyme with this catalytic specificity. The 508-amino acid polypeptide displays a unique arrangement of three distinct modular domains. Each domain shows...

  18. Enzymatic solubilization of a pectinaceous dietary fiber fraction from potato pulp: Optimization of the fiber extraction process

    DEFF Research Database (Denmark)

    Meyer, Anne S.; Dam, Birgitte P; Lærke, Helle N.

    2009-01-01

    Upgrading of potato pulp, a byproduct stream from industrial manufacture of potato starch, is important for the continued economic competitiveness of the potato starch industry. The major part of potato pulp consists of the tuber plant cell wall material which is particularly rich in galactan...... branched rhamnogalacturonan I type pectin. In the work reported here, the release of high-molecular weight pectinaceous dietary fiber polysaccharides from starch free potato pulp was accomplished by use of a multicomponent pectinase preparation from Aspergillus aculeatus (Viscozyme® L). The enzyme reaction...... that they were rich in galactose and uronic acid indicating that the solubilized fibers were mainly made up of galactan branched rhamnogalacturonan I type pectin polymers....

  19. Arm injury produces long-term behavioral and neural hypersensitivity in octopus.

    Science.gov (United States)

    Alupay, Jean S; Hadjisolomou, Stavros P; Crook, Robyn J

    2014-01-13

    Cephalopod molluscs are the most neurally and behaviorally complex invertebrates, with brains rivaling those of some vertebrates in size and complexity. This has fostered the opinion that cephalopods, particularly octopuses, may experience vertebrate-like pain when injured. However, it is not known whether octopuses possess nociceptors or if their somatic sensory neurons exhibit sensitization after injury. Here we show that the octopus Abdopus aculeatus expresses nocifensive behaviors including arm autotomy, and displays marked neural hyperexcitability both in injured and uninjured arms for at least 24h after injury. These findings do not demonstrate that octopuses experience pain-like states; instead they add to the minimal existing literature on how cephalopods receive, process, and integrate noxious sensory information, potentially informing and refining regulations governing use of cephalopods in scientific research.

  20. Aspergillus uvarum sp. nov., an uniseriate black Aspergillus species isolated from grapes in Europe

    DEFF Research Database (Denmark)

    Perrone, Giancarlo; Varga, János; Susca, Antonia

    2008-01-01

    A novel species, Aspergillus uvarum sp. nov., is described within Aspergillus section Nigri. This species can be distinguished from other black aspergilli based on internal transcribed spacers (ITS), beta-tubulin and calmodulin gene sequences, by AFLP analysis and by extrolite profiles. Aspergillus...... uvarum sp. nov. isolates produced secalonic acid, common to other Aspergillus japonicus-related taxa, and geodin, erdin and dihydrogeodin, which are not produced by any other black aspergilli. None of the isolates were found to produce ochratoxin A. The novel species is most closely related to two...... atypical strains of Aspergillus aculeatus, CBS 114.80 and CBS 620.78, and was isolated from grape berries in Portugal, Italy, France, Israel, Greece and Spain. The type strain of Aspergillus uvarum sp. nov. is IMI 388523(T)=CBS 127591(T)= ITEM 4834(T)= IBT26606(T)....

  1. Review of secondary metabolites and mycotoxins from the Aspergillus niger group

    DEFF Research Database (Denmark)

    Nielsen, Kristian Fog; Mogensen, Jesper Mølgaard; Johansen, Maria

    2009-01-01

    Filamentous fungi in the Aspergillus section Nigri (the black aspergilli) represent some of the most widespread food and feed contaminants known but they are also some of the most important workhorses used by the biotechnological industry. The Nigri section consists of six commonly found species...... (excluding A. aculeatus and its close relatives) from which currently 145 different secondary metabolites have been isolated and/or detected. From a human and animal safety point of view, the mycotoxins ochratoxin A (from A. carbonarius and less frequently A. niger) and fumonisin B2 (from A. niger...... since it is consistently produced by A. tubingensis (177 of 177 strains tested) and A. acidus (47 of 47 strains tested) but never by A. niger (140 strains tested). Naptho-γ-pyrones are the compounds produced in the highest quantities and are produced by all six common species in the group (A. niger 134...

  2. DRIFTSEL: an R package for detecting signals of natural selection in quantitative traits.

    Science.gov (United States)

    Karhunen, M; Merilä, J; Leinonen, T; Cano, J M; Ovaskainen, O

    2013-07-01

    Approaches and tools to differentiate between natural selection and genetic drift as causes of population differentiation are of frequent demand in evolutionary biology. Based on the approach of Ovaskainen et al. (2011), we have developed an R package (DRIFTSEL) that can be used to differentiate between stabilizing selection, diversifying selection and random genetic drift as causes of population differentiation in quantitative traits when neutral marker and quantitative genetic data are available. Apart from illustrating the use of this method and the interpretation of results using simulated data, we apply the package on data from three-spined sticklebacks (Gasterosteus aculeatus) to highlight its virtues. DRIFTSEL can also be used to perform usual quantitative genetic analyses in common-garden study designs. © 2013 John Wiley & Sons Ltd.

  3. Nickel oxide nanoparticles film produced by dead biomass of filamentous fungus

    Science.gov (United States)

    Salvadori, Marcia Regina; Nascimento, Cláudio Augusto Oller; Corrêa, Benedito

    2014-09-01

    The synthesis of nickel oxide nanoparticles in film form using dead biomass of the filamentous fungus Aspergillus aculeatus as reducing agent represents an environmentally friendly nanotechnological innovation. The optimal conditions and the capacity of dead biomass to uptake and produce nanoparticles were evaluated by analyzing the biosorption of nickel by the fungus. The structural characteristics of the film-forming nickel oxide nanoparticles were analyzed by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and atomic force microscopy (AFM). These techniques showed that the nickel oxide nanoparticles had a size of about 5.89 nm and were involved in a protein matrix which probably permitted their organization in film form. The production and uptake of nickel oxide nanoparticles organized in film form by dead fungal biomass bring us closer to sustainable strategies for the biosynthesis of metal oxide nanoparticles.

  4. The Effect of Salinity on Egg Development and Viability of Schistocephalus solidus (Cestoda: Diphyllobothriidea).

    Science.gov (United States)

    Simmonds, Natalie E; Barber, Iain

    2016-02-01

    Schistocephalus solidus plerocercoids commonly infect three-spined stickleback Gasterosteus aculeatus populations in brackish and freshwaters, but infections are typically absent from marine populations. Here we provide an experimental test of the salinity tolerance of S. solidus eggs, to determine the role of salinity in limiting the distribution of infection in coastal zones. We find that S. solidus eggs, derived from the in vitro culture of 3 different plerocercoids, developed normally in salinities of up to 12.5‰, but above this egg viability dropped rapidly, and no egg hatching was observed at salinities above 20‰. Our results are consistent with the distribution of infections in natural stickleback populations and add resolution to previous descriptive observations on salinity tolerance in S. solidus. They also demonstrate that S. solidus presents a novel disease challenge to marine populations of three-spined sticklebacks entering brackish and freshwater environments.

  5. Wild food plants used on the Dubrovnik coast (south-eastern Croatia

    Directory of Open Access Journals (Sweden)

    Katija Dolina

    2014-09-01

    Full Text Available Croatia’s versatile plant use traditions are still not sufficiently documented. The aim of this study was to record local traditions of wild food plant use on the Dubrovnik coast. We interviewed 40 inhabitants of 23 villages, mainly knowledgeable informants. On average 19 species were listed, which in total produced an inventory of 95 food plant species (including species whose leaves or inflorescences are used as recreational teas. The most commonly collected are: Sonchus oleraceus and S. asper, Asparagus acutifolius, Dioscorea communis, Cichorium intybus, Crepis zacintha, Allium ampeloprasum, Picris echioides and Foeniculum vulgare (all of them used as vegetables, the fruits of Rubus ulmifolius (mainly eaten raw, the fruits of roses (Rosa sempervirens and R. canina and the leaves of Salvia officinalis (both roses and salvia are used for making recreational teas. A particular feature of the local gastronomy is the collection of young Ruscus aculeatus shoots.

  6. Ecological causes of morphological evolution in the three-spined stickleback.

    Science.gov (United States)

    Spence, Rowena; Wootton, Robert J; Barber, Iain; Przybylski, Mirosław; Smith, Carl

    2013-06-01

    The central assumption of evolutionary theory is that natural selection drives the adaptation of populations to local environmental conditions, resulting in the evolution of adaptive phenotypes. The three-spined stickleback (Gasterosteus aculeatus) displays remarkable phenotypic variation, offering an unusually tractable model for understanding the ecological mechanisms underpinning adaptive evolutionary change. Using populations on North Uist, Scotland we investigated the role of predation pressure and calcium limitation on the adaptive evolution of stickleback morphology and behavior. Dissolved calcium was a significant predictor of plate and spine morph, while predator abundance was not. Stickleback latency to emerge from a refuge varied with morph, with populations with highly reduced plates and spines and high predation risk less bold. Our findings support strong directional selection in three-spined stickleback evolution, driven by multiple selective agents.

  7. Short-and long term niche segregation and individual specialization of brown trout (Salmo trutta) in species poor Faroese lakes

    DEFF Research Database (Denmark)

    Brodersen, Jakob; Malmquist, Hilmar J.; Landkildehus, Frank

    2012-01-01

    by comparing relative abundance, stable isotope ratios and diet in multiple habitats. In the presence of three-spined sticklebacks (Gasterosteus aculeatus), a higher proportion of the trout population was found in the pelagic habitat, and trout in general relied on a more pelagic diet base as compared to trout...... living in allopatry or in sympatry with Arctic charr (Salvelinus alpinus). Diet analyses revealed, however, that niche-segregation may be more complex than described on a one-dimensional pelagic-littoral axis. Trout from both littoral and offshore benthic habitats had in the presence of sticklebacks...... a less benthic diet as compared to trout living in allopatry or in sympatry with charr. Furthermore, we found individual habitat specialization between littoral/benthic and pelagic trout in deep lakes. Hence, our findings indicate that for trout populations interspecific competition can drive shifts...

  8. Male competition fitness landscapes predict both forward and reverse speciation.

    Science.gov (United States)

    Keagy, Jason; Lettieri, Liliana; Boughman, Janette W

    2016-01-01

    Speciation is facilitated when selection generates a rugged fitness landscape such that populations occupy different peaks separated by valleys. Competition for food resources is a strong ecological force that can generate such divergent selection. However, it is unclear whether intrasexual competition over resources that provide mating opportunities can generate rugged fitness landscapes that foster speciation. Here we use highly variable male F2 hybrids of benthic and limnetic threespine sticklebacks, Gasterosteus aculeatus Linnaeus, 1758, to quantify the male competition fitness landscape. We find that disruptive sexual selection generates two fitness peaks corresponding closely to the male phenotypes of the two parental species, favouring divergence. Most surprisingly, an additional region of high fitness favours novel hybrid phenotypes that correspond to those observed in a recent case of reverse speciation after anthropogenic disturbance. Our results reveal that sexual selection through male competition plays an integral role in both forward and reverse speciation.

  9. 中国耳孔蜈蚣属(蜈蚣目:蜈蚣科)部分种类研究%On Some Centipede Species of the Genus Otostigmus From China (Scolopendromorpha: Scolopendridae)

    Institute of Scientific and Technical Information of China (English)

    宋志顺; 盖永华; 宋大祥; 朱明生

    2005-01-01

    记述我国蜈蚣目Scolopendromorph耳孔蜈蚣亚科Otosigminae耳孔蜈蚣属Otostigmus(耳孔蜈蚣亚属Otostigmus)6种.其中对平耳孔蜈蚣Otostigmus(Otostigmuts)politus Karsch、糙耳孔蜈蚣O.(O.)scaber Porat和多刺耳孔蜈蚣O.(O.)aculeatus Hasse进行了重新描述;马氏耳孔蜈蚣O.(O.)martensi Lewis和贝氏耳孔蜈蚣O.(O.)beroni Lewis为2个我国新记录;刘易斯耳孔蜈蚣O.(O.)lewisi sp.nov.为1新种.附有各种特征图,并编制了种检索表.

  10. Validation and application of HPLC-ESI-MS/MS method for the quantification of RBBR decolorization, a model for highly toxic molecules, using several fungi strains.

    Science.gov (United States)

    Perlatti, Bruno; da Silva, Maria Fátima das Graças Fernandes; Fernandes, João Batista; Forim, Moacir Rossi

    2012-11-01

    A novel analytical method using HPLC-MS/MS operating in selected reaction monitoring (SRM) for evaluation of fungi efficacy to decolorize Remazol Brilliant Blue R (RBBR) dye solution was developed, validated and applied. The method shows high sensibility allowing the detection of 4.6 pM of RBBR. Four fungal strains were tested in liquid medium, three strains of Aspergillus (Aspergillus aculeatus, Aspergillus flavus and Aspergillus fumigatus) and Phanerochaete chrysosporium. All fungi were able to degrade the dye, with efficiencies ranging from 40% for P. chrysosporium up to 99% for A. flavus during a 30-day incubation period. During the experiment, increased accumulation of degradation products was observed in A. flavus cultures containing RBBR. Through the use of full scan HPLC-MS technique it was possible to propose the biogenesis of the microbial metabolic degradation pathway. Screening using microorganisms and RBBR may be hereafter used to investigate microbial biodegradation of high toxicity molecules such as dioxins.

  11. Analysis Of Phytochemical Constituents And Antimicrobial Activities Of Alpinia calcarata Against Clinical Pathogens

    Directory of Open Access Journals (Sweden)

    Jency George

    2014-09-01

    Full Text Available To study the antimicrobial activity and phytochemical characterization of essential oil isolated from the rhizome of Alpinia calcarata against pathogenic bacteria and fungi. Fresh rhizomes of Alpinia calcarata were subjected to hydro distillation process to obtain essential oil and characterized by Gas Chromatography- Mass Spectroscopy (GC-MS. The essential oil was evaluated for antibacterial and antifungal activity against ten pathogenic bacteria and seven fungi by the disc diffusion method. GC – MS analysis of the essential oil extracted from the rhizome of Alpinia calcarata contained the derivatives of 2-octanone, camphene, 1,8-cineole, α fenchyl acetate, 2 hexanone, 4 methyl- 2- hexanone and other minor compounds. The antimicrobial activity of the oil showed significant inhibitory activity against the human pathogenic bacteria, no activity was observed against the fungi Aspergillus aculeatus and Fusarium oxysporum. The findings of the present study indicate that the rhizome extract of Alpinia calcarata possess secondary metabolites and potential to develop antimicrobial drugs.

  12. Parasites of sticklebacks (Actinopterygii: Gasterosteidae) from South-Eastern Baltic Sea (Poland).

    Science.gov (United States)

    Sulgostowska, Teresa; Vojtkova, Ludmila

    2005-01-01

    A total of 142 individuals of Gasterosteus aculeatus L. and 22 individuals of Pungitius pungitius (L.) from several areas of the coastal waters of the Gdańsk Bay both brackish- and freshwater were examined for parasites. The survey was carried out within 1988-1991. Six parasite species, namely: Gyrodactylus arcuatus, Apatemon gracilis, Sphaerostomum bramae, Phyllodistomumfolium, Neoechinorhynchus rutili, and Argulus foliaceus were recovered from sticklebacks caught in freshwater habitats; while the other 4 parasites: Apatemon annuligerum, Bothriocephalus sp., Schistocephalus solidus, Proteocephalus percae occurred only in fish from brackish-water areas. Additional 5 parasites: Trichodina domerguei, Diplostomum pungitii, Diplostomum spathaceum, Rhaphidascaris acus, and Thersitina gasterostei were recorded in fishes from both habitats.

  13. [Isolation of Aspergillus section Nigri strains in yerba mate in Posadas (Misiones, Argentina) and evaluation of their ochratoxigenic potential].

    Science.gov (United States)

    Castrillo, María L; Horianski, Marta A; Jerke, Gladis

    2013-01-01

    The objectives of the present work were to investigate the isolation frequency of genus Aspergillus in canchada yerba mate (YMCH) and elaborated yerba mate (YME) (Ilex paraguariensis) and the proportion of section Nigri isolates, as well as to determine ochratoxin A production by Aspergillus species section Nigri. Three hundred twenty eight Aspergillus strains from 20 samples of YMCH and 1306 Aspergillus strains from 36 samples of YME were isolated; of the total, 279 from the first group of strains and 1215 from the latter group, belonged to section Nigri. For the detection of ochratoxin A production, the strains were cultivated on Czapeck yeast extract agar and the toxin was detected by thin layer chromatography under UV light. Uniserate species predominance was observed in the 1494 strains of Aspergillus section Nigri obtained (Aspergillus japonicus var. japonicus and Aspergillus japonicus var. aculeatus), whereas none of the strains analysed showed ochratoxin A production in vitro at the detection level of the methodology employed.

  14. The Isolation and Identification of Endophytic Fungi Producing Flavonoids in Sugarcane Leaves%产黄酮甘蔗叶内生真菌的分离与鉴定

    Institute of Scientific and Technical Information of China (English)

    周宁; 赵晓璐; 谢庆武

    2016-01-01

    采用显色反应、薄层层析色谱和紫外吸收光谱法,对甘蔗叶内16株内生真菌的代谢产物进行黄酮类化合物检测.结果共筛选到3株能够产黄酮类化合物的内生真菌(GZ-1、GZ-4和GZ-5).依据真菌的形态特征及ITS序列分析,鉴定结果表明菌株GZ-1、GZ-5为棘孢曲霉(Aspergillus aculeatus),菌株GZ-4为黑曲霉(Aspergillus niger).

  15. Olfactory receptor gene family evolution in stickleback and medaka fishes

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Interaction of olfactory receptor (OR) genes with environmental odors is regarded as the first step of olfaction.In this study,OR genes of two fish,medaka (Oryzias latipes) and stickleback (Gasterosteus aculeatus),were identified and an evolutional analysis was conducted.The selection pressure of different TM regions and complete coding region were compared.Three TM regions (TM4,TM5 and TM6) were found to have higher average Ka/Ks values,which might be partly caused by positive selection as suggested by subsequent positive selection analysis.Further analysis showed that many PTSs overlap,or are adjacent to previously deduced binding sites in mammals.These results support the hypothesis that binding sites of fish OR genes may evolved under positive selection.

  16. Biodegradation of 1,2,3,4-tetrachlorodibenzo-p-dioxin in liquid broth by brown-rot fungi.

    Science.gov (United States)

    Perlatti, Bruno; da Silva, Maria Fátima das Graças Fernandes; Fernandes, João Batista; Forim, Moacir Rossi

    2013-11-01

    Dioxins are a class of extremely hazardous molecules that might pose a threat to the environment. This work evaluated the microbial degradation of 1,2,3,4-tetrachlorodibenzo-p-dioxin (1,2,3,4-TCDD), in liquid broth using three brown-rot fungi and one white-rot fungi as control. A fast and reliable extraction method with recoveries of over 98% together with a validated GC-MS method was developed, and applied to quantify 1,2,3,4-TCDD in liquid broth, mycelia and reaction flask, with detection limits of 10 ppb. Among the four strains tested, brown-rot fungus Aspergillus aculeatus showed best results, removing up to 21% of dioxin after 30-day incubation. The results open both a path for biotechnological interest in bioremediation purposes and environmental behavior studies by using brown-rot fungus.

  17. Predation of Threespine Stickleback by Dragonfly Naiads.

    Science.gov (United States)

    Lescak, Emily A; von Hippel, Frank A; Lohman, Brian K; Sherbick, Mary L

    2012-10-01

    Threespine stickleback (Gasterosteus aculeatus) populations that have evolved pelvic girdle reduction are most commonly found in lakes with low dissolved ion concentration, a lack of piscivorous fishes, and abundant macroinvertebrate predators. Researchers have speculated that macroinvertebrates have a propensity to consume prey with pelvic spines. If this is true, perhaps macroinvertebrates use the stickleback's spines to facilitate capture and manipulation. This study tested whether dragonfly naiads differentially prey upon stickleback possessing either a complete or reduced pelvis and documented naiad hunting and capturing behavior. Results from an arena experiment suggest that naiads do not prey more heavily upon individuals with one pelvic phenotype over the other. However, results from trials where the naiads were presented with one stickleback with pelvic spines and another without suggest that naiads prey more heavily upon small stickleback with pelvic spines and large stickleback without pelvic spines and that they adjust their predatory behavior based upon the pelvic phenotype of the prey.

  18. Coral reef fish perceive lightness illusions

    Science.gov (United States)

    Simpson, Elisha E.; Marshall, N. Justin; Cheney, Karen L.

    2016-01-01

    Visual illusions occur when information from images are perceived differently from the actual physical properties of the stimulus in terms of brightness, size, colour and/or motion. Illusions are therefore important tools for sensory perception research and from an ecological perspective, relevant for visually guided animals viewing signals in heterogeneous environments. Here, we tested whether fish perceived a lightness cube illusion in which identical coloured targets appear (for humans) to return different spectral outputs depending on the apparent amount of illumination they are perceived to be under. Triggerfish (Rhinecanthus aculeatus) were trained to peck at coloured targets to receive food rewards, and were shown to experience similar shifts in colour perception when targets were placed in illusory shadows. Fish therefore appear to experience similar simultaneous contrast mechanisms to humans, even when targets are embedded in complex, scene-type illusions. Studies such as these help unlock the fundamental principles of visual system mechanisms. PMID:27748401

  19. Different phylogenomic approaches to resolve the evolutionary relationships among model fish species.

    Science.gov (United States)

    Negrisolo, Enrico; Kuhl, Heiner; Forcato, Claudio; Vitulo, Nicola; Reinhardt, Richard; Patarnello, Tomaso; Bargelloni, Luca

    2010-12-01

    Comparative genomics holds the promise to magnify the information obtained from individual genome sequencing projects, revealing common features conserved across genomes and identifying lineage-specific characteristics. To implement such a comparative approach, a robust phylogenetic framework is required to accurately reconstruct evolution at the genome level. Among vertebrate taxa, teleosts represent the second best characterized group, with high-quality draft genome sequences for five model species (Danio rerio, Gasterosteus aculeatus, Oryzias latipes, Takifugu rubripes, and Tetraodon nigroviridis), and several others are in the finishing lane. However, the relationships among the acanthomorph teleost model fishes remain an unresolved taxonomic issue. Here, a genomic region spanning over 1.2 million base pairs was sequenced in the teleost fish Dicentrarchus labrax. Together with genomic data available for the above fish models, the new sequence was used to identify unique orthologous genomic regions shared across all target taxa. Different strategies were applied to produce robust multiple gene and genomic alignments spanning from 11,802 to 186,474 amino acid/nucleotide positions. Ten data sets were analyzed according to Bayesian inference, maximum likelihood, maximum parsimony, and neighbor joining methods. Extensive analyses were performed to explore the influence of several factors (e.g., alignment methodology, substitution model, data set partitions, and long-branch attraction) on the tree topology. Although a general consensus was observed for a closer relationship between G. aculeatus (Gasterosteidae) and Di. labrax (Moronidae) with the atherinomorph O. latipes (Beloniformes) sister taxon of this clade, with the tetraodontiform group Ta. rubripes and Te. nigroviridis (Tetraodontiformes) representing a more distantly related taxon among acanthomorph model fish species, conflicting results were obtained between data sets and methods, especially with respect

  20. Variáveis que influenciam a produção de celulases e xilanase por espécies de Aspergillus

    Directory of Open Access Journals (Sweden)

    Marilia Ribeiro Sales

    2010-11-01

    Full Text Available O objetivo deste trabalho foi determinar as variáveis que influenciam a produção simultânea de celulases e xilanase por Aspergillus aculeatus URM 4953 e A. phoenicis URM 4924, com uso de bagaço de cana-de-açúcar como substrato. As variáveis avaliadas foram pH inicial, tempo de cultivo, concentração do substrato, agitação, concentração do inóculo, temperatura, tipo de bagaço de cana-de-açúcar e espécie de Aspergillus. Foi utilizado o planejamento fatorial fracionário 2(8-4, com três repetições no ponto central. Todas as variáveis analisadas influenciaram a produção de pelo menos uma das enzimas. As maiores atividades enzimáticas observadas foram: celulases totais, 0,45 UI mL-1; endoglucanase, 0,60 UI mL-1; exoglucanase, 0,17 U mL-1 ; celobiase 6,42 UI mL-1; e xilanase, 30,05 U mL-1. As melhores condições para produção das enzimas foram: pH 6,0; tempo de cultivo de 168 horas; bagaço de cana-de-açúcar residual como substrato; e A. aculeatus URM 4953, que produziu as celulases e a xilanase simultaneamente. As variáveis que influenciam a produção simultânea das celulases e xilanase são pH, tempo de cultivo, tipo de bagaço de cana-de-açúcar e espécie de Aspergillus.

  1. Platypus globin genes and flanking loci suggest a new insertional model for beta-globin evolution in birds and mammals.

    Science.gov (United States)

    Patel, Vidushi S; Cooper, Steven J B; Deakin, Janine E; Fulton, Bob; Graves, Tina; Warren, Wesley C; Wilson, Richard K; Graves, Jennifer A M

    2008-07-25

    Vertebrate alpha (alpha)- and beta (beta)-globin gene families exemplify the way in which genomes evolve to produce functional complexity. From tandem duplication of a single globin locus, the alpha- and beta-globin clusters expanded, and then were separated onto different chromosomes. The previous finding of a fossil beta-globin gene (omega) in the marsupial alpha-cluster, however, suggested that duplication of the alpha-beta cluster onto two chromosomes, followed by lineage-specific gene loss and duplication, produced paralogous alpha- and beta-globin clusters in birds and mammals. Here we analyse genomic data from an egg-laying monotreme mammal, the platypus (Ornithorhynchus anatinus), to explore haemoglobin evolution at the stem of the mammalian radiation. The platypus alpha-globin cluster (chromosome 21) contains embryonic and adult alpha- globin genes, a beta-like omega-globin gene, and the GBY globin gene with homology to cytoglobin, arranged as 5'-zeta-zeta'-alphaD-alpha3-alpha2-alpha1-omega-GBY-3'. The platypus beta-globin cluster (chromosome 2) contains single embryonic and adult globin genes arranged as 5'-epsilon-beta-3'. Surprisingly, all of these globin genes were expressed in some adult tissues. Comparison of flanking sequences revealed that all jawed vertebrate alpha-globin clusters are flanked by MPG-C16orf35 and LUC7L, whereas all bird and mammal beta-globin clusters are embedded in olfactory genes. Thus, the mammalian alpha- and beta-globin clusters are orthologous to the bird alpha- and beta-globin clusters respectively. We propose that alpha- and beta-globin clusters evolved from an ancient MPG-C16orf35-alpha-beta-GBY-LUC7L arrangement 410 million years ago. A copy of the original beta (represented by omega in marsupials and monotremes) was inserted into an array of olfactory genes before the amniote radiation (>315 million years ago), then duplicated and diverged to form orthologous clusters of beta-globin genes with different expression

  2. Receptors in the bill of the platypus.

    Science.gov (United States)

    Gregory, J E; Iggo, A; McIntyre, A K; Proske, U

    1988-01-01

    receptors were characterized by their low threshold to mechanical stimuli, irregular discharge and significant dynamic sensitivity. Vibration receptors showed maintained responses to sinusoidal vibration of the skin up to 600 Hz. 7. These experiments confirm an earlier report that the platypus bill is an electrodetector organ. The presence of electroreceptors of a unique structure and supplied by the trigeminal nerve indicates that electroreception has evolved independently in monotremes. This in turn emphasizes that monotremes are a highly evolved group which split off from the main mammalian stem a long time ago. Images Plate 1 PMID:3418529

  3. Evolution of the patellar sesamoid bone in mammals

    Science.gov (United States)

    Samuels, Mark E.; Regnault, Sophie

    2017-01-01

    The patella is a sesamoid bone located in the major extensor tendon of the knee joint, in the hindlimb of many tetrapods. Although numerous aspects of knee morphology are ancient and conserved among most tetrapods, the evolutionary occurrence of an ossified patella is highly variable. Among extant (crown clade) groups it is found in most birds, most lizards, the monotreme mammals and almost all placental mammals, but it is absent in most marsupial mammals as well as many reptiles. Here, we integrate data from the literature and first-hand studies of fossil and recent skeletal remains to reconstruct the evolution of the mammalian patella. We infer that bony patellae most likely evolved between four and six times in crown group Mammalia: in monotremes, in the extinct multituberculates, in one or more stem-mammal genera outside of therian or eutherian mammals and up to three times in therian mammals. Furthermore, an ossified patella was lost several times in mammals, not including those with absent hindlimbs: once or more in marsupials (with some re-acquisition) and at least once in bats. Our inferences about patellar evolution in mammals are reciprocally informed by the existence of several human genetic conditions in which the patella is either absent or severely reduced. Clearly, development of the patella is under close genomic control, although its responsiveness to its mechanical environment is also important (and perhaps variable among taxa). Where a bony patella is present it plays an important role in hindlimb function, especially in resisting gravity by providing an enhanced lever system for the knee joint. Yet the evolutionary origins, persistence and modifications of a patella in diverse groups with widely varying habits and habitats—from digging to running to aquatic, small or large body sizes, bipeds or quadrupeds—remain complex and perplexing, impeding a conclusive synthesis of form, function, development and genetics across mammalian evolution

  4. Evolution of the patellar sesamoid bone in mammals

    Directory of Open Access Journals (Sweden)

    Mark E. Samuels

    2017-03-01

    Full Text Available The patella is a sesamoid bone located in the major extensor tendon of the knee joint, in the hindlimb of many tetrapods. Although numerous aspects of knee morphology are ancient and conserved among most tetrapods, the evolutionary occurrence of an ossified patella is highly variable. Among extant (crown clade groups it is found in most birds, most lizards, the monotreme mammals and almost all placental mammals, but it is absent in most marsupial mammals as well as many reptiles. Here, we integrate data from the literature and first-hand studies of fossil and recent skeletal remains to reconstruct the evolution of the mammalian patella. We infer that bony patellae most likely evolved between four and six times in crown group Mammalia: in monotremes, in the extinct multituberculates, in one or more stem-mammal genera outside of therian or eutherian mammals and up to three times in therian mammals. Furthermore, an ossified patella was lost several times in mammals, not including those with absent hindlimbs: once or more in marsupials (with some re-acquisition and at least once in bats. Our inferences about patellar evolution in mammals are reciprocally informed by the existence of several human genetic conditions in which the patella is either absent or severely reduced. Clearly, development of the patella is under close genomic control, although its responsiveness to its mechanical environment is also important (and perhaps variable among taxa. Where a bony patella is present it plays an important role in hindlimb function, especially in resisting gravity by providing an enhanced lever system for the knee joint. Yet the evolutionary origins, persistence and modifications of a patella in diverse groups with widely varying habits and habitats—from digging to running to aquatic, small or large body sizes, bipeds or quadrupeds—remain complex and perplexing, impeding a conclusive synthesis of form, function, development and genetics across

  5. Platypus globin genes and flanking loci suggest a new insertional model for beta-globin evolution in birds and mammals

    Directory of Open Access Journals (Sweden)

    Warren Wesley C

    2008-07-01

    Full Text Available Abstract Background Vertebrate alpha (α- and beta (β-globin gene families exemplify the way in which genomes evolve to produce functional complexity. From tandem duplication of a single globin locus, the α- and β-globin clusters expanded, and then were separated onto different chromosomes. The previous finding of a fossil β-globin gene (ω in the marsupial α-cluster, however, suggested that duplication of the α-β cluster onto two chromosomes, followed by lineage-specific gene loss and duplication, produced paralogous α- and β-globin clusters in birds and mammals. Here we analyse genomic data from an egg-laying monotreme mammal, the platypus (Ornithorhynchus anatinus, to explore haemoglobin evolution at the stem of the mammalian radiation. Results The platypus α-globin cluster (chromosome 21 contains embryonic and adult α- globin genes, a β-like ω-globin gene, and the GBY globin gene with homology to cytoglobin, arranged as 5'-ζ-ζ'-αD-α3-α2-α1-ω-GBY-3'. The platypus β-globin cluster (chromosome 2 contains single embryonic and adult globin genes arranged as 5'-ε-β-3'. Surprisingly, all of these globin genes were expressed in some adult tissues. Comparison of flanking sequences revealed that all jawed vertebrate α-globin clusters are flanked by MPG-C16orf35 and LUC7L, whereas all bird and mammal β-globin clusters are embedded in olfactory genes. Thus, the mammalian α- and β-globin clusters are orthologous to the bird α- and β-globin clusters respectively. Conclusion We propose that α- and β-globin clusters evolved from an ancient MPG-C16orf35-α-β-GBY-LUC7L arrangement 410 million years ago. A copy of the original β (represented by ω in marsupials and monotremes was inserted into an array of olfactory genes before the amniote radiation (>315 million years ago, then duplicated and diverged to form orthologous clusters of β-globin genes with different expression profiles in different lineages.

  6. The Molecular Architecture for the Intermediate Filaments of Hard [alpha]-Keratin Based on the Superlattice Data Obtained from a Study ofMammals Using Synchrotron Fibre Diffraction

    Energy Technology Data Exchange (ETDEWEB)

    James, Veronica (ANU)

    2014-09-24

    High- and low-angle X-ray diffraction studies of hard {alpha}-keratin have been studied, and various models have been proposed over the last 70 years. Most of these studies have been confined to one or two forms of alpha keratin. This high- and low-angle synchrotron fibre diffraction study extends the study to cover all available data for all known forms of hard {alpha}-keratin including hairs, fingernails, hooves, horn, and quills from mammals, marsupials, and a monotreme, and it confirms that the model proposed is universally acceptable for all mammals. A complete Bragg analysis of the meridional diffraction patterns, including multiple-time exposures to verify any weak reflections, verified the existence of a superlattice consisting of two infinite lattices and three finite lattices. An analysis of the equatorial patterns establishes the radii of the oligomeric levels of dimers, tetramers, and intermediate filaments (IFs) together with the centre to centre distance for the IFs, thus confirming the proposed helices within helices molecular architecture for hard {alpha}-keratin. The results verify that the structure proposed by Feughelman and James meets the criteria for a valid {alpha}-keratin structure.

  7. Widespread horizontal transfer of retrotransposons.

    Science.gov (United States)

    Walsh, Ali Morton; Kortschak, R Daniel; Gardner, Michael G; Bertozzi, Terry; Adelson, David L

    2013-01-15

    In higher organisms such as vertebrates, it is generally believed that lateral transfer of genetic information does not readily occur, with the exception of retroviral infection. However, horizontal transfer (HT) of protein coding repetitive elements is the simplest way to explain the patchy distribution of BovB, a long interspersed element (LINE) about 3.2 kb long, that has been found in ruminants, marsupials, squamates, monotremes, and African mammals. BovB sequences are a major component of some of these genomes. Here we show that HT of BovB is significantly more widespread than believed, and we demonstrate the existence of two plausible arthropod vectors, specifically reptile ticks. A phylogenetic tree built from BovB sequences from species in all of these groups does not conform to expected evolutionary relationships of the species, and our analysis indicates that at least nine HT events are required to explain the observed topology. Our results provide compelling evidence for HT of genetic material that has transformed vertebrate genomes.

  8. The head and neck muscles of the serval and tiger: homologies, evolution, and proposal of a mammalian and a veterinary muscle ontology.

    Science.gov (United States)

    Diogo, Rui; Pastor, Francisco; De Paz, Felix; Potau, Josep M; Bello-Hellegouarch, Gaëlle; Ferrero, Eva M; Fisher, Rebecca E

    2012-12-01

    Here we describe the head and neck muscles of members of the two extant felid subfamilies (Leptailurus serval: Felinae; Panthera tigris: Pantherinae) and compare these muscles with those of other felids, other carnivorans (e.g., domestic dogs), other eutherian mammals (e.g., rats, tree-shrews and modern humans), and noneutherian mammals including monotremes. Another major goal of the article is to discuss and help clarify nomenclatural discrepancies found in the Nomina Anatomica Veterinaria and in veterinary atlases and textbooks that use cats and dogs as models to understand the anatomy of domestic mammals and to stress differences with modern humans. We propose a unifying nomenclature that is expanded to all the head and neck muscles and to all mammalian taxa in order to help build veterinary and mammalian muscle ontologies. Our observations and comparisons and the specific use of this nomenclature point out that felids such as tigers and servals and other carnivorans such as dogs have more facial muscle structures related to the mobility of both the auricular and orbital regions than numerous other mammals, including modern humans, which might be the result of an ancient adaptation related to the remarkable predatory capacities of carnivorans. Interestingly, the skeletal differences, mainly concerning the hyoid apparatus, pharynx, and larynx, that are likely associated with the different types of vocalizations seen in the Felinae (mainly purring) and Pantherinae (mainly roaring) are not accompanied by clear differences in the musculature connected to these structures in the feline L. serval and the pantherine P. tigris.

  9. The evolutionary history of testicular externalization and the origin of the scrotum

    Indian Academy of Sciences (India)

    Karel Kleisner; Richard Ivell; Jaroslav Flegr

    2010-03-01

    This paper re-examines the evolution of the scrotum and testicular descent in the context of the recent phylogeny of mammals. The adaptive significance of testicular descent and scrotality is briefly discussed. We mapped four character states reflecting the position of testes and presence of scrotum onto recent mammalian phylogeny. Our results are interpreted as follows: as to the presence of testicondy in Monotremata and most of Atlantogenata, which represent the basal group of all eutherians, we argue that primary testicondy represents a plesiomorphic condition for Eutheria as well as for all mammals. This is in opposition to the previous hypothesis of Werdelin and Nilsonne that the scrotum may have evolved before the origin of mammals and then repeatedly disappeared in many groups including monotremes. We suggest that the scrotum evolved at least twice during the evolutionary history of mammals, within Marsupialia and Boreoeutheria, and has subsequently been lost by many groups; this trend is especially strong in Laurasiatheria. We suggest that the recent diversity in testicular position within mammals is the result of multiple selection pressures stemming from the need to provide conditions suitable for sperm development and storage, or to protect the male gonads from excessive physical and physiological disturbance.

  10. Origin of INSL3-mediated testicular descent in therian mammals.

    Science.gov (United States)

    Park, Jae-Il; Semyonov, Jenia; Chang, Chia Lin; Yi, Wei; Warren, Wesley; Hsu, Sheau Yu Teddy

    2008-06-01

    Testicular descent is a unique physiological adaptation found in therian mammals allowing optimal spermatogenesis below core body temperature. Recent studies show that INSL3, produced by Leydig cells, and its receptor LGR8 (RXFP2) are essential for mediating the transabdominal phase of testicular descent during early development. However, the origin and genetic basis for this physiological adaptation is not clear. Using syntenic mapping and the functional characterization of contemporary and resurrected relaxin family hormones, we show that derivation of INSL3-mediated testicular descent involved the duplication of an ancestral RLN3-like gene that encodes an indiscriminate ligand for LGR7 (RXFP1) and LGR8. This event was followed by acquisition of the LGR7-selective characteristics by a daughter gene (RLN3) prior to the evolution of the common ancestor of monotremes, marsupials, and placentals. A subsequent mutation of the other daughter gene (INSL3) occurred before the emergence of therian mammals, which then led to the derivation of the reciprocal LGR8-specific characteristics of INSL3. The stepwise evolution of these independent signaling pathways through gene duplication and subsequent divergence is consistent with Darwinian theory of selection and adaptation, and the temporal proximity suggests an association between these genetic events and the concurrent evolution of testicular descent in ancestral therian mammals.

  11. Passive electroreception in aquatic mammals.

    Science.gov (United States)

    Czech-Damal, Nicole U; Dehnhardt, Guido; Manger, Paul; Hanke, Wolf

    2013-06-01

    Passive electroreception is a sensory modality in many aquatic vertebrates, predominantly fishes. Using passive electroreception, the animal can detect and analyze electric fields in its environment. Most electric fields in the environment are of biogenic origin, often produced by prey items. These electric fields can be relatively strong and can be a highly valuable source of information for a predator, as underlined by the fact that electroreception has evolved multiple times independently. The only mammals that possess electroreception are the platypus (Ornithorhynchus anatinus) and the echidnas (Tachyglossidae) from the monotreme order, and, recently discovered, the Guiana dolphin (Sotalia guianensis) from the cetacean order. Here we review the morphology, function and origin of the electroreceptors in the two aquatic species, the platypus and the Guiana dolphin. The morphology shows certain similarities, also similar to ampullary electroreceptors in fishes, that provide cues for the search for electroreceptors in more vertebrate and invertebrate species. The function of these organs appears to be very similar. Both species search for prey animals in low-visibility conditions or while digging in the substrate, and sensory thresholds are within one order of magnitude. The electroreceptors in both species are innervated by the trigeminal nerve. The origin of the accessory structures, however, is completely different; electroreceptors in the platypus have developed from skin glands, in the Guiana dolphin, from the vibrissal system.

  12. Vascularization of the gray whale palate (Cetacea, Mysticeti, Eschrichtius robustus): soft tissue evidence for an alveolar source of blood to baleen.

    Science.gov (United States)

    Ekdale, Eric G; Deméré, Thomas A; Berta, Annalisa

    2015-04-01

    The origin of baleen in mysticetes heralded a major transition during cetacean evolution. Extant mysticetes are edentulous in adulthood, but rudimentary teeth develop in utero within open maxillary and mandibular alveolar grooves. The teeth are resorbed prenatally and the alveolar grooves close as baleen germ develops. Arteries supplying blood to highly vascularized epithelial tissue from which baleen develops pass through lateral nutrient foramina in the area of the embryonic alveolar grooves and rudimentary teeth. Those vessels are hypothesized to be branches of the superior alveolar artery, but branches of the greater palatine arteries may play a role in the baleen vascularization. Through a combination of latex injection, CT, and traditional dissection of the palate of a neonatal gray whale (Eschrichtius robustus), we confirm that the baleen receives blood from vessels within the superior alveolar canal via the lateral foramina. The greater palatine artery is restricted to its own passage with no connections to the baleen. This study has implications for the presence of baleen in extinct taxa by identifying the vessels and bony canals that supply blood to the epithelium from which baleen develops. The results indicate that the lateral foramina in edentulous mysticete fossils are bony correlates for the presence of baleen, and the results can be used to help identify bony canals and foramina that have been used to reconstruct baleen in extinct mysticetes that retained teeth in adulthood. Further comparisons are made with mammals that also possess oral keratin structures, including ruminants, ornithorhynchid monotremes, and sirenians.

  13. The nocturnal bottleneck and the evolution of activity patterns in mammals

    Science.gov (United States)

    Gerkema, Menno P.; Davies, Wayne I. L.; Foster, Russell G.; Menaker, Michael; Hut, Roelof A.

    2013-01-01

    In 1942, Walls described the concept of a ‘nocturnal bottleneck’ in placental mammals, where these species could survive only by avoiding daytime activity during times in which dinosaurs were the dominant taxon. Walls based this concept of a longer episode of nocturnality in early eutherian mammals by comparing the visual systems of reptiles, birds and all three extant taxa of the mammalian lineage, namely the monotremes, marsupials (now included in the metatherians) and placentals (included in the eutherians). This review describes the status of what has become known as the nocturnal bottleneck hypothesis, giving an overview of the chronobiological patterns of activity. We review the ecological plausibility that the activity patterns of (early) eutherian mammals were restricted to the night, based on arguments relating to endothermia, energy balance, foraging and predation, taking into account recent palaeontological information. We also assess genes, relating to light detection (visual and non-visual systems) and the photolyase DNA protection system that were lost in the eutherian mammalian lineage. Our conclusion presently is that arguments in favour of the nocturnal bottleneck hypothesis in eutherians prevail. PMID:23825205

  14. Identification of a novel PNMA-MS1 gene in marsupials suggests the LTR retrotransposon-derived PNMA genes evolved differently in marsupials and eutherians.

    Science.gov (United States)

    Iwasaki, Sawa; Suzuki, Shunsuke; Pelekanos, Matthew; Clark, Helen; Ono, Ryuichi; Shaw, Geoff; Renfree, Marilyn B; Kaneko-Ishino, Tomoko; Ishino, Fumitoshi

    2013-10-01

    Two major gene families derived from Ty3/Gypsy long terminal repeat (LTR) retrotransposons were recently identified in mammals. The sushi-ichi retrotransposon homologue (SIRH) family comprises 12 genes: 11 in eutherians including Peg10 and Peg11/Rtl1 that have essential roles in the eutherian placenta and 1 that is marsupial specific. Fifteen and 12 genes were reported in the second gene family, para-neoplastic antigen MA (PNMA), in humans and mice, respectively, although their biological functions and evolutionary history remain largely unknown. Here, we identified two novel candidate PNMA genes, PNMA-MS1 and -MS2 in marsupials. Like all eutherian-specific PNMA genes, they exhibit the highest homology to a Gypsy12_DR (DR, Danio rerio) Gag protein. PNMA-MS1 is conserved in both Australian and South American marsupial species, the tammar wallaby and grey short-tailed opossum. However, no PNMA-MS1 orthologue was found in eutherians, monotremes or non-mammalian vertebrates. PNMA-MS1 was expressed in the ovary, mammary gland and brain during development and growth in the tammar, suggesting that PNMA-MS1 may have acquired a marsupial-specific function. However, PNMA-MS2 seems to be a pseudogene. The absence of marsupial orthologues of eutherian PNMA genes suggests that the retrotransposition events of the Gypsy12_DR-related retrotransposons that gave rise to the PNMA family occurred after the divergence of marsupials and eutherians.

  15. Morphological and molecular evolution of the ultimobranchial gland of nonmammalian vertebrates, with special reference to the chicken C cells.

    Science.gov (United States)

    Kameda, Yoko

    2017-10-01

    This review summarizes the current understanding of the nonmammalian ultimobranchial gland from morphological and molecular perspectives. Ultimobranchial anlage of all animal species develops from the last pharyngeal pouch. The genes involved in the development of pharyngeal pouches are well conserved across vertebrates. The ultimobranchial anlage of nonmammalian vertebrates and monotremes does not merge with the thyroid, remaining as an independent organ throughout adulthood. Although C cells of all animal species secrete calcitonin, the shape, cellular components and location of the ultimobranchial gland vary from species to species. Avian ultimobranchial gland is unique in several phylogenic aspects; the organ is located between the vagus and recurrent laryngeal nerves at the upper thorax and is densely innervated by branches emanating from them. In chick embryos, TuJ1-, HNK-1-, and PGP 9.5-immunoreactive cells that originate from the distal vagal (nodose) ganglion, colonize the ultimobranchial anlage and differentiate into C cells; neuronal cells give rise to C cells. Like C cells of mammals, the cells of fishes, amphibians, reptiles, and also a subset of C cells of birds, appear to be derived from the endodermal epithelium forming ultimobranchial anlage. Thus, the avian ultimobranchial C cells may have dual origins, neural progenitors and endodermal epithelium. Developmental Dynamics 246:719-739, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  16. A comparative approach to understanding tissue-specific expression of uncoupling protein 1 expression in adipose tissue

    Directory of Open Access Journals (Sweden)

    Andrew eShore

    2013-01-01

    Full Text Available The thermoregulatory function of brown adipose tissue (BAT is due to the tissue-specific expression of uncoupling protein 1 (UCP1 which is thought to have evolved in early mammals. We report that a CpG island close to the UCP1 transcription start site is highly conserved in all 29 vertebrates examined apart from the mouse and xenopus. Using methylation sensitive restriction digest and bisulphite mapping we show that the CpG island in both the bovine and human is largely un-methylated and is not related to differences in UCP1 expression between white and brown adipose tissue. Tissue-specific expression of UCP1 has been proposed to be regulated by a conserved 5’ distal enhancer which has been reported to be absent in marsupials. We demonstrate that the enhancer, is also absent in 5 eutherians as well as marsupials, monotremes, amphibians and fish, is present in pigs despite UCP1 having become a pseudogene, and that absence of the enhancer element does not relate to brown adipose tissue-specific UCP1 expression. We identify an additional putative 5’ regulatory unit which is conserved in 14 eutherian species but absent in other eutherians and vertebrates, but again unrelated to UCP1 expression. We conclude that despite clear evidence of conservation of regulatory elements in the UCP1 5’ untranslated region, this does not appear to be related to species or tissues-specific expression of UCP1.

  17. Weird mammals provide insights into the evolution of mammalian sex chromosomes and dosage compensation

    Indian Academy of Sciences (India)

    Jennifer A. Marshall Graves

    2015-12-01

    The deep divergence of mammalian groups 166 and 190 million years ago (MYA) provide genetic variation to explore the evolution of DNA sequence, gene arrangement and regulation of gene expression in mammals. With encouragement from the founder of the field, Mary Lyon, techniques in cytogenetics and molecular biology were progressively adapted to characterize the sex chromosomes of kangaroos and other marsupials, platypus and echidna—and weird rodent species. Comparative gene mapping reveals the process of sex chromosome evolution from their inception 190 MYA (they are autosomal in platypus) to their inevitable end (the Y has disappeared in two rodent lineages). Our X and Y are relatively young, getting their start with the evolution of the sex-determining gene, which triggered progressive degradation of the Y chromosome. Even more recently, sex chromosomes of placental mammals fused with an autosomal region which now makes up most of the Y. Exploration of gene activity patterns over four decades showed that dosage compensation via X-chromosome inactivation is unique to therian mammals, and that this whole chromosome control process is different in marsupials and absent in monotremes and reptiles, and birds. These differences can be exploited to deduce how mammalian sex chromosomes and epigenetic silencing evolved.

  18. First Molecular Characterization of Theileria ornithorhynchi Mackerras, 1959: yet Another Challenge to the Systematics of the Piroplasms.

    Science.gov (United States)

    Paparini, Andrea; Macgregor, James; Ryan, Una M; Irwin, Peter J

    2015-12-01

    Piroplasms, tick-transmitted Apicomplexa of the genera Theileria, Babesia and Cytauxzoon, are blood-borne parasites of clinical and veterinary importance. The order Piroplasmida shows a puzzling systematics characterized by multiple clades, soft polytomies and paraphyletic/polyphyletic genera. In the present study, screening of platypuses (Ornithorhynchus anatinus), was performed to infer the parasite molecular phylogeny. DNA was extracted from blood, ectoparasites and tick eggs and the 18S rRNA- hsp70-genes were used for the phylogenetic reconstructions. Microscopic analyses detected pleomorphic intra-erythrocytic organisms and tetrads consistent with previous descriptions of Theileria ornithorhynchi Mackerras, 1959, but observation of possible schizonts could not be confirmed. DNA sequences obtained from blood and ticks allowed resolving the systematics of the first piroplasm infecting a monotreme host. Molecularly, T. ornithorhynchi formed a novel monophyletic group, basal to most known piroplasms' clades. The ancestral position of this clade, isolated from an ancient lineage of mammalian host appears particularly fascinating. The present paper discusses the inadequacies of the current molecular systematics for the Piroplasmida and the consequences of incomplete sampling, morphology-based classification and ambiguous microscopic identifications. Likely when the current sampling bias is rectified and more sequence data is made available, the phylogenetic position of T. ornithorhynchi will be further contextualized without ambiguity. Copyright © 2015 Elsevier GmbH. All rights reserved.

  19. Phylogenetic origins of early alterations in brain region proportions.

    Science.gov (United States)

    Charvet, Christine J; Sandoval, Alexis L; Striedter, Georg F

    2010-01-01

    Adult galliform birds (e.g. chickens) exhibit a relatively small telencephalon and a proportionately large optic tectum compared with parrots and songbirds. We previously examined the embryonic origins of these adult species differences and found that the optic tectum is larger in quail than in parakeets and songbirds at early stages of development, prior to tectal neurogenesis onset. The aim of this study was to determine whether a proportionately large presumptive tectum is a primitive condition within birds or a derived feature of quail and other galliform birds. To this end, we examined embryonic brains of several avian species (emus, parrots, songbirds, waterfowl, galliform birds), reptiles (3 lizard species, alligators, turtles) and a monotreme (platypuses). Brain region volumes were estimated from serial Nissl-stained sections. We found that the embryos of galliform birds and lizards exhibit a proportionally larger presumptive tectum than all the other examined species. The presumptive tectum of the platypus is unusually small. The most parsimonious interpretation of these data is that the expanded embryonic tectum of lizards and galliform birds is a derived feature in both of these taxonomic groups.

  20. Evolution and survival on eutherian sex chromosomes.

    Directory of Open Access Journals (Sweden)

    Melissa A Wilson

    2009-07-01

    Full Text Available Since the two eutherian sex chromosomes diverged from an ancestral autosomal pair, the X has remained relatively gene-rich, while the Y has lost most of its genes through the accumulation of deleterious mutations in nonrecombining regions. Presently, it is unclear what is distinctive about genes that remain on the Y chromosome, when the sex chromosomes acquired their unique evolutionary rates, and whether X-Y gene divergence paralleled that of paralogs located on autosomes. To tackle these questions, here we juxtaposed the evolution of X and Y homologous genes (gametologs in eutherian mammals with their autosomal orthologs in marsupial and monotreme mammals. We discovered that genes on the X and Y acquired distinct evolutionary rates immediately following the suppression of recombination between the two sex chromosomes. The Y-linked genes evolved at higher rates, while the X-linked genes maintained the lower evolutionary rates of the ancestral autosomal genes. These distinct rates have been maintained throughout the evolution of X and Y. Specifically, in humans, most X gametologs and, curiously, also most Y gametologs evolved under stronger purifying selection than similarly aged autosomal paralogs. Finally, after evaluating the current experimental data from the literature, we concluded that unique mRNA/protein expression patterns and functions acquired by Y (versus X gametologs likely contributed to their retention. Our results also suggest that either the boundary between sex chromosome strata 3 and 4 should be shifted or that stratum 3 should be divided into two strata.

  1. Physical mapping of the elephant X chromosome: conservation of gene order over 105 million years.

    Science.gov (United States)

    Delgado, Claudia Leticia Rodríguez; Waters, Paul D; Gilbert, Clément; Robinson, Terence J; Graves, Jennifer A Marshall

    2009-01-01

    All therian mammals (eutherians and marsupials) have an XX female/XY male sex chromosome system or some variant of it. The X and Y evolved from a homologous pair of autosomes over the 166 million years since therian mammals diverged from monotremes. Comparing the sex chromosomes of eutherians and marsupials defined an ancient X conserved region that is shared between species of these mammalian clades. However, the eutherian X (and the Y) was augmented by a recent addition (XAR) that is autosomal in marsupials. XAR is part of the X in primates, rodents, and artiodactyls (which belong to the eutherian clade Boreoeutheria), but it is uncertain whether XAR is part of the X chromosome in more distantly related eutherian mammals. Here we report on the gene content and order on the X of the elephant (Loxodonta africana)-a representative of Afrotheria, a basal endemic clade of African mammals-and compare these findings to those of other documented eutherian species. A total of 17 genes were mapped to the elephant X chromosome. Our results support the hypothesis that the eutherian X and Y chromosomes were augmented by the addition of autosomal material prior to eutherian radiation. Not only does the elephant X bear the same suite of genes as other eutherian X chromosomes, but gene order appears to have been maintained across 105 million years of evolution, perhaps reflecting strong constraints posed by the eutherian X inactivation system.

  2. Reassessing the relationship between brain size, life history, and metabolism at the marsupial/placental dichotomy.

    Science.gov (United States)

    Weisbecker, Vera; Goswami, Anjali

    2014-09-01

    A vigorous discussion surrounds the question as to what enables some mammals--including primates and cetaceans--to evolve large brains. We recently published a study suggesting that the radiation of marsupial mammals is highly relevant to this question because of the unique reproductive and metabolic traits within this clade. In particular, we controversially suggested that marsupial brain sizes are not systematically smaller than those of placentals, and that elevated basal metabolic rates (BMR) are not linked to larger marsupial brains. As our dataset was found to contain some erroneous body size data, derived from a published source, we here use an updated and corrected dataset and employ standard as well as phylogenetically corrected analyses to re-assess and elaborate on our original conclusions. Our proposal that marsupials are not systematically smaller-brained than placentals remains supported, particularly when the unusually large-brained placental clade, Primates, is excluded. Use of the new dataset not only confirms that high metabolic rates are not associated with larger brain size in marsupials, but we additionally find some support for a striking negative correlation between BMR and brain size. The best supported correlates of large brain size remain the reproductive traits of weaning age and litter size. These results support our suggestion that mammalian brain sizes (including, by inference, those of monotremes) are predominantly constrained by the ability of females to fuel the growth of their offspring's large brains, rather than by the maintenance requirements of the adult brain.

  3. Status of dosage compensation of X chromosome in bovine genome.

    Science.gov (United States)

    Ka, Sojeong; Ahn, Hyeonju; Seo, Minseok; Kim, Heebal; Kim, Jin Nam; Lee, Hyun-Jeong

    2016-08-01

    Dosage compensation system with X chromosome upregulation and inactivation have evolved to overcome the genetic imbalance between sex chromosomes in both male and female of mammals. Although recent development of chromosome-wide technologies has allowed us to test X upregulation, discrete data processing and analysis methods draw disparate conclusions. A series of expression studies revealed status of dosage compensation in some species belonging to monotremes, marsupials, rodents and primates. However, X upregulation in the Artiodactyla order including cattle have not been studied yet. In this study, we surveyed the genome-wide transcriptional upregulation in X chromosome in cattle RNA-seq data using different gene filtration methods. Overall examination of RNA-seq data revealed that X chromosome in the pituitary gland expressed more genes than in other peripheral tissues, which was consistent with the previous results observed in human and mouse. When analyzed with globally expressed genes, a median X:A expression ratio was 0.94. The ratio of 1-to-1 ortholog genes between chicken and mammals, however, showed considerable reduction to 0.68. These results indicate that status of dosage compensation for cattle is not deviated from those found in rodents and primate, and this is consistent with the evolutionary history of cattle.

  4. Characterisation of the immune compounds in koala milk using a combined transcriptomic and proteomic approach

    Science.gov (United States)

    Morris, Katrina M.; O’Meally, Denis; Zaw, Thiri; Song, Xiaomin; Gillett, Amber; Molloy, Mark P.; Polkinghorne, Adam; Belov, Katherine

    2016-01-01

    Production of milk is a key characteristic of mammals, but the features of lactation vary greatly between monotreme, marsupial and eutherian mammals. Marsupials have a short gestation followed by a long lactation period, and milk constituents vary greatly across lactation. Marsupials are born immunologically naïve and rely on their mother’s milk for immunological protection. Koalas (Phascolarctos cinereus) are an iconic Australian species that are increasingly threatened by disease. Here we use a mammary transcriptome, two milk proteomes and the koala genome to comprehensively characterise the protein components of koala milk across lactation, with a focus on immune constituents. The most abundant proteins were well-characterised milk proteins, including β-lactoglobulin and lactotransferrin. In the mammary transcriptome, 851 immune transcripts were expressed, including immunoglobulins and complement components. We identified many abundant antimicrobial peptides, as well as novel proteins with potential antimicrobial roles. We discovered that marsupial VELP is an ortholog of eutherian Glycam1, and likely has an antimicrobial function in milk. We also identified highly-abundant koala endogenous-retrovirus sequences, identifying a potential transmission route from mother to young. Characterising the immune components of milk is key to understanding protection of marsupial young, and the novel immune compounds identified may have applications in clinical research. PMID:27713568

  5. Extreme telomere length dimorphism in the Tasmanian devil and related marsupials suggests parental control of telomere length.

    Directory of Open Access Journals (Sweden)

    Hannah S Bender

    Full Text Available Telomeres, specialised structures that protect chromosome ends, play a critical role in preserving chromosome integrity. Telomere dynamics in the Tasmanian devil (Sarcophilus harrisii are of particular interest in light of the emergence of devil facial tumour disease (DFTD, a transmissible malignancy that causes rapid mortality and threatens the species with extinction. We used fluorescent in situ hybridisation to investigate telomere length in DFTD cells, in healthy Tasmanian devils and in four closely related marsupial species. Here we report that animals in the Order Dasyuromorphia have chromosomes characterised by striking telomere length dimorphism between homologues. Findings in sex chromosomes suggest that telomere length dimorphism may be regulated by events in the parental germlines. Long telomeres on the Y chromosome imply that telomere lengthening occurs during spermatogenesis, whereas telomere diminution occurs during oogenesis. Although found in several somatic cell tissue types, telomere length dimorphism was not found in DFTD cancer cells, which are characterised by uniformly short telomeres. This is, to our knowledge, the first report of naturally occurring telomere length dimorphism in any species and suggests a novel strategy of telomere length control. Comparative studies in five distantly related marsupials and a monotreme indicate that telomere dimorphism evolved at least 50 million years ago.

  6. Fast running restricts evolutionary change of the vertebral column in mammals.

    Science.gov (United States)

    Galis, Frietson; Carrier, David R; van Alphen, Joris; van der Mije, Steven D; Van Dooren, Tom J M; Metz, Johan A J; ten Broek, Clara M A

    2014-08-05

    The mammalian vertebral column is highly variable, reflecting adaptations to a wide range of lifestyles, from burrowing in moles to flying in bats. However, in many taxa, the number of trunk vertebrae is surprisingly constant. We argue that this constancy results from strong selection against initial changes of these numbers in fast running and agile mammals, whereas such selection is weak in slower-running, sturdier mammals. The rationale is that changes of the number of trunk vertebrae require homeotic transformations from trunk into sacral vertebrae, or vice versa, and mutations toward such transformations generally produce transitional lumbosacral vertebrae that are incompletely fused to the sacrum. We hypothesize that such incomplete homeotic transformations impair flexibility of the lumbosacral joint and thereby threaten survival in species that depend on axial mobility for speed and agility. Such transformations will only marginally affect performance in slow, sturdy species, so that sufficient individuals with transitional vertebrae survive to allow eventual evolutionary changes of trunk vertebral numbers. We present data on fast and slow carnivores and artiodactyls and on slow afrotherians and monotremes that strongly support this hypothesis. The conclusion is that the selective constraints on the count of trunk vertebrae stem from a combination of developmental and biomechanical constraints.

  7. [Current views on vision of mammals].

    Science.gov (United States)

    Khokhlova, T V

    2012-01-01

    In the review, research data are presented on mammals' vision including visual pigments, color and contrast vision, and visual behaviour in different species. It is shown that in course of evolution mammals were gradually losing the elements of daylight cone vision system that are typical of other vertebrates. In monotremes, visual pigments SWS2 (cone blue-sensitive 2) and MWS/LWS (green/red-sensitive) are still present, as well as rod RH1. Theria, except some primates, also have two cone visual pigments: SWS1 (ultraviolet/violet or blue-sensitive 1) and MWS/LWS along with rod RH1. Humans and some other higher primates evolved the new visual pigment, MWS, and acquired trichromatic vision. Marine mammals (cetaceans and pinnipeds) and some species of other orders have lost also the visual pigment SWS1, probably due to specificity of processing the information received by these cones. Current view on mammals' vision with two cone pigments and rods is presented. Data on maximum spectral sensitivity of visual pigments in different species and orders are given along with data on spatial contrast sensation. High visual acuity has been acquired by ungulates, artiodactyls, and primates, while the highest one--by humans with their specialized fovea.

  8. Non-coding RNAs and the acquisition of genomic imprinting in mammals

    Institute of Scientific and Technical Information of China (English)

    ZHANG YiJun; QU LiangHu

    2009-01-01

    Genomic imprinting, representing parent-specific expression of alleles at a locus, Is mainly evident in flowering plants and placental mammals. Most imprinted genes, including numerous non-coding RNAs, are located in clusters regulated by imprinting control regions (ICRs). The acquisition and evolution of genomic imprinting is among the most fundamental genetic questions. Discoveries about the transition of mammalian imprinted gene domains from their non-imprinted ancestors, especially recent studies undertaken on the most ancient mammalian clades - the marsupials and monotremes from which model species genomes have recently been sequenced, are of high value. By reviewing and analyzing these studies, a close connection between non-coding RNAs and the acquisition of genomic imprinting in mammals is demonstrated. The evidence comes from two observations accompanied with the ac-quisition of the imprinting: (i) many novel non-coding RNA genes emerged in imprinted regions; (ii) the expressions of some conserved non-coding RNAs have changed dramatically. Furthermore, a system-atical analysis of imprinted snoRNA (small nucleolar RNA) genes from 15 vertebrates suggests that the origination of imprinted snoRNAs occurred after the divergence between eutherians and marsupials, followed by a rapid expansion leading to the fixation of major gene families in the eutherian ancestor prior to the radiation of modern placental mammals. Involved in the regulation of imprinted silencing and mediating the ohromatins epigenetic modification may be the major roles that non-coding RNAs play during the acquisition of genomic imprinting in mammals.

  9. Microsatellite landscape evolutionary dynamics across 450 million years of vertebrate genome evolution.

    Science.gov (United States)

    Adams, Richard H; Blackmon, Heath; Reyes-Velasco, Jacobo; Schield, Drew R; Card, Daren C; Andrew, Audra L; Waynewood, Nyimah; Castoe, Todd A

    2016-05-01

    The evolutionary dynamics of simple sequence repeats (SSRs or microsatellites) across the vertebrate tree of life remain largely undocumented and poorly understood. In this study, we analyzed patterns of genomic microsatellite abundance and evolution across 71 vertebrate genomes. The highest abundances of microsatellites exist in the genomes of ray-finned fishes, squamate reptiles, and mammals, while crocodilian, turtle, and avian genomes exhibit reduced microsatellite landscapes. We used comparative methods to infer evolutionary rates of change in microsatellite abundance across vertebrates and to highlight particular lineages that have experienced unusually high or low rates of change in genomic microsatellite abundance. Overall, most variation in microsatellite content, abundance, and evolutionary rate is observed among major lineages of reptiles, yet we found that several deeply divergent clades (i.e., squamate reptiles and mammals) contained relatively similar genomic microsatellite compositions. Archosauromorph reptiles (turtles, crocodilians, and birds) exhibit reduced genomic microsatellite content and the slowest rates of microsatellite evolution, in contrast to squamate reptile genomes that have among the highest rates of microsatellite evolution. Substantial branch-specific shifts in SSR content in primates, monotremes, rodents, snakes, and fish are also evident. Collectively, our results support multiple major shifts in microsatellite genomic landscapes among vertebrates.

  10. Mast cells are present in the choroid of the normal eye in most vertebrate classes.

    Science.gov (United States)

    McMenamin, Paul Gerard; Polla, Emily

    2013-07-01

    Mast cells are bone marrow-derived tissue-homing leukocytes, which have traditionally been regarded as effector cells in allergic disorders, responses against parasites, and regulation of blood flow, but a broader perspective of their functional heterogeneity, such as immunomodulation, angiogenesis, tissue repair, and remodeling after injury, is now emerging. The persistence of mast cells in connective tissues throughout the evolution of vertebrates is evidence of strong selective pressure suggesting that these cells must have multiple beneficial and important roles in normal homeostasis. While mast cells are present within the uveal tract of eutherian mammals, there is little known about their presence in the choroid of other vertebrate classes. Eye tissues from a range of vertebrate species (fish, amphibian, reptiles, birds, marsupials, monotreme, and eutherian mammals) were investigated. Tissues were fixed in either 2% glutaraldehyde, 2% paraformaldehyde or a mixture of both and processed for resin embedding. Semi-thin sections of the retina and choroid were cut and stained with toluidine blue. Mast cells were identified in the choroid of all classes of vertebrates investigated except sharks. Their morphology, location, and staining characteristics were remarkably similar from teleost fish through to eutherian mammals and bore close morphological resemblance to mammalian connective tissue mast cells. The similar morphology and distribution of mast cells in the choroid of all vertebrate classes studied suggest a basic physiological function that has been retained since the evolution of the vertebrate eye. © 2013 American College of Veterinary Ophthalmologists.

  11. Recurrent gene loss correlates with the evolution of stomach phenotypes in gnathostome history.

    Science.gov (United States)

    Castro, L Filipe C; Gonçalves, Odete; Mazan, Sylvie; Tay, Boon-Hui; Venkatesh, Byrappa; Wilson, Jonathan M

    2014-01-22

    The stomach, a hallmark of gnathostome evolution, represents a unique anatomical innovation characterized by the presence of acid- and pepsin-secreting glands. However, the occurrence of these glands in gnathostome species is not universal; in the nineteenth century the French zoologist Cuvier first noted that some teleosts lacked a stomach. Strikingly, Holocephali (chimaeras), dipnoids (lungfish) and monotremes (egg-laying mammals) also lack acid secretion and a gastric cellular phenotype. Here, we test the hypothesis that loss of the gastric phenotype is correlated with the loss of key gastric genes. We investigated species from all the main gnathostome lineages and show the specific contribution of gene loss to the widespread distribution of the agastric condition. We establish that the stomach loss correlates with the persistent and complete absence of the gastric function gene kit--H(+)/K(+)-ATPase (Atp4A and Atp4B) and pepsinogens (Pga, Pgc, Cym)--in the analysed species. We also find that in gastric species the pepsinogen gene complement varies significantly (e.g. two to four in teleosts and tens in some mammals) with multiple events of pseudogenization identified in various lineages. We propose that relaxation of purifying selection in pepsinogen genes and possibly proton pump genes in response to dietary changes led to the numerous independent events of stomach loss in gnathostome history. Significantly, the absence of the gastric genes predicts that reinvention of the stomach in agastric lineages would be highly improbable, in line with Dollo's principle.

  12. Evolution and the neurosciences down-under.

    Science.gov (United States)

    Macmillan, Malcolm

    2009-01-01

    At the end of the nineteenth and the beginning of the twentieth century three Australians made notable contributions to founding the neurosciences: Alfred Walter Campbell (1868-1937) conducted the first extensive histological studies of the human brain; Grafton Elliot Smith (1871-1937) studied the monotreme brain and established the basis for understanding the mammalian brain; and Stanley David Porteus (1883-1972) extended his studies of intellectual disability to encompass the relation between brain size and intelligence. The work of each was decisively influenced by important members of the Edinburgh medical school or by Edinburgh medical graduates: William Turner (1832-1916) and William Rutherford (1839-1899) Professors of Anatomy and Physiology respectively at Edinburgh; James Thomas Wilson (1861-1945) Professor of Anatomy at the University of Sydney; and Richard James Arthur Berry (1867-1962) Professor of Anatomy at the University of Melbourne. An important aspect of the influence on the Australians was a materialist view of brain function but the work of all was most important for a theory even more central held by the Scots who had influenced them: Darwin's theory of evolution. The importance of the work of Campbell and especially that of Smith for Darwinism is contrasted with Darwin's own indifference to the peculiarities of the Australian fauna he observed when he visited Australia during HMS Beagle's voyage of discovery in 1836.

  13. Pattern of the divergence of olfactory receptor genes during tetrapod evolution.

    Directory of Open Access Journals (Sweden)

    Takushi Kishida

    Full Text Available The olfactory receptor (OR multigene family is responsible for the sense of smell in vertebrate species. OR genes are scattered widely in our chromosomes and constitute one of the largest gene families in eutherian genomes. Some previous studies revealed that eutherian OR genes diverged mainly during early mammalian evolution. However, the exact period when, and the ecological reason why eutherian ORs strongly diverged has remained unclear. In this study, I performed a strict data mining effort for marsupial opossum OR sequences and bootstrap analyses to estimate the periods of chromosomal migrations and gene duplications of OR genes during tetrapod evolution. The results indicate that chromosomal migrations occurred mainly during early vertebrate evolution before the monotreme-placental split, and that gene duplications occurred mainly during early mammalian evolution between the bird-mammal split and marsupial-placental split, coinciding with the reduction of opsin genes in primitive mammals. It could be thought that the previous chromosomal dispersal allowed the OR genes to subsequently expand easily, and the nocturnal adaptation of early mammals might have triggered the OR gene expansion.

  14. The nocturnal bottleneck and the evolution of activity patterns in mammals.

    Science.gov (United States)

    Gerkema, Menno P; Davies, Wayne I L; Foster, Russell G; Menaker, Michael; Hut, Roelof A

    2013-08-22

    In 1942, Walls described the concept of a 'nocturnal bottleneck' in placental mammals, where these species could survive only by avoiding daytime activity during times in which dinosaurs were the dominant taxon. Walls based this concept of a longer episode of nocturnality in early eutherian mammals by comparing the visual systems of reptiles, birds and all three extant taxa of the mammalian lineage, namely the monotremes, marsupials (now included in the metatherians) and placentals (included in the eutherians). This review describes the status of what has become known as the nocturnal bottleneck hypothesis, giving an overview of the chronobiological patterns of activity. We review the ecological plausibility that the activity patterns of (early) eutherian mammals were restricted to the night, based on arguments relating to endothermia, energy balance, foraging and predation, taking into account recent palaeontological information. We also assess genes, relating to light detection (visual and non-visual systems) and the photolyase DNA protection system that were lost in the eutherian mammalian lineage. Our conclusion presently is that arguments in favour of the nocturnal bottleneck hypothesis in eutherians prevail.

  15. Evolution of V genes from the TRV loci of mammals.

    Science.gov (United States)

    Olivieri, David N; Gambón-Cerdá, Santiago; Gambón-Deza, Francisco

    2015-07-01

    Information concerning the evolution of T lymphocyte receptors (TCR) can be deciphered from that part of the molecule that recognizes antigen presented by major histocompatibility complex (MHC), namely the variable (V) regions. The genes that code for these variable regions are found within the TCR loci. Here, we describe a study of the evolutionary origin of V genes that code for the α and β chains of the TCR loci of mammals. In particular, we demonstrate that most of the 35 TRAV and 25 TRBV conserved genes found in Primates are also found in other Eutheria, while in Marsupials, Monotremes, and Reptiles, these genes diversified in a different manner. We also show that in mammals, all TRAV genes are derived from five ancestral genes, while all TRBV genes originate from four such genes. In Reptiles, the five TRAV and three out of the four TRBV ancestral genes exist, as well as other V genes not found in mammals. We also studied the TRGV and TRDV loci from all mammals, and we show a relationship of the TRDV to the TRAV locus throughout evolutionary time.

  16. Evolution of the mammalian dentate gyrus.

    Science.gov (United States)

    Hevner, Robert F

    2016-02-15

    The dentate gyrus (DG), a part of the hippocampal formation, has important functions in learning, memory, and adult neurogenesis. Compared with homologous areas in sauropsids (birds and reptiles), the mammalian DG is larger and exhibits qualitatively different phenotypes: 1) folded (C- or V-shaped) granule neuron layer, concave toward the hilus and delimited by a hippocampal fissure; 2) nonperiventricular adult neurogenesis; and 3) prolonged ontogeny, involving extensive abventricular (basal) migration and proliferation of neural stem and progenitor cells (NSPCs). Although gaps remain, available data indicate that these DG traits are present in all orders of mammals, including monotremes and marsupials. The exception is Cetacea (whales, dolphins, and porpoises), in which DG size, convolution, and adult neurogenesis have undergone evolutionary regression. Parsimony suggests that increased growth and convolution of the DG arose in stem mammals concurrently with nonperiventricular adult hippocampal neurogenesis and basal migration of NSPCs during development. These traits could all result from an evolutionary change that enhanced radial migration of NSPCs out of the periventricular zones, possibly by epithelial-mesenchymal transition, to colonize and maintain nonperiventricular proliferative niches. In turn, increased NSPC migration and clonal expansion might be a consequence of growth in the cortical hem (medial patterning center), which produces morphogens such as Wnt3a, generates Cajal-Retzius neurons, and is regulated by Lhx2. Finally, correlations between DG convolution and neocortical gyrification (or capacity for gyrification) suggest that enhanced abventricular migration and proliferation of NSPCs played a transformative role in growth and folding of neocortex as well as archicortex.

  17. Improving retting of fibre through genetic modification of flax to express pectinases.

    Science.gov (United States)

    Musialak, Magdalena; Wróbel-Kwiatkowska, Magdalena; Kulma, Anna; Starzycka, Eligia; Szopa, Jan

    2008-02-01

    Flax (Linum usitatissimum L.) is a raw material used for important industrial products. Linen has very high quality textile properties, such as its strength, water absorption, comfort and feel. However, it occupies less than 1% of the total textile market. The major reason for this is the long and difficult retting process by which linen fibres are obtained. In retting, bast fibre bundles are separated from the core, the epidermis and the cuticle. This is accomplished by the cleavage of pectins and hemicellulose in the flax cell wall, a process mainly carried out by plant pathogens like filamentous fungi. The remaining bast fibres are mainly composed of cellulose and lignin. The aim of this study was to generate plants that could be retted more efficiently. To accomplish this, we employed the novel approach of transgenic flax plant generation with increased polygalacturonase (PGI ) and rhamnogalacturonase (RHA) activities. The constitutive expression of Aspergillus aculeatus genes resulted in a significant reduction in the pectin content in tissue-cultured and field-grown plants. This pectin content reduction was accompanied by a significantly higher (more than 2-fold) retting efficiency of the transgenic plant fibres as measured by a modified Fried's test. No alteration in the lignin or cellulose content was observed in the transgenic plants relative to the control. This indicates that the over-expression of the two enzymes does not affect flax fibre composition. The growth rate and soluble sugar and starch contents were in the range of the control levels. It is interesting to note that the RHA and PGI plants showed higher resistance to Fusarium culmorum and F. oxysporum attack, which correlates with the increased phenolic acid level. In this report, we demonstrate for the first time that over-expression of the A. aculeatus genes results in flax plants more readily usable for fibre production. The biochemical parameters of the cell wall components indicated that

  18. The spider family Selenopidae (Arachnida, Araneae in Australia and Asia

    Directory of Open Access Journals (Sweden)

    Sarah Crews

    2011-05-01

    monotypic and contains P. formosanus (Kayashima comb. n. known only from Taiwan. Finally, Selenops aculeatus Simon is transferred to the genus Siamspinops, forming the new combination S. aculeatus (Simon comb. n. The distribution and diversity of the Australasian selenopid fauna is discussed. Keys are provided to all of the selenopid genera and to the species of Karaops and Makdiops.

  19. Influencia de los coadyuvantes tecnológicos utilizados en el proceso de elaboración de aceite de oliva sobre la cinética del proceso de digestión anaerobia del alpechín

    Directory of Open Access Journals (Sweden)

    Borja Padilla, R.

    1992-08-01

    Full Text Available A kinetic study of the anaerobic digestion of olive mill wastewater, which was obtained with the technological helper "Olivex" (Carbohydrase -pectinases, cellulases and hemicellulases- from the Aspergillus aculeatus was carried out. An identical wastewater, obtained without this enzymatic formulation was also used. The process was carried out in bioreactors with microorganisms immobilized on two micronized clay supports, Sepiolite and Bentonite. The methane volume-time data pairs obtained were used to calculate the specific rate constant, Ko, by using the Roediger's equation. A decrease of the specific rate constant value was observed over the substrate concentration studied when the volume of wastewater added was increased; this confirmed the occurrence of an inhibition process, which was more marked for the olive mill wastewater obtained with Olivex. The Levenspiel's model was used to obtain the inhibition constants of this process.

    Se ha efectuado un estudio cinético del proceso de digestión anaerobia de un alpechín obtenido con el coadyuvante tecnológico "Olivex" (Carbohidrasa -pectinasas, celulasas y hemicelulasas- procedente de Aspergillus aculeatus en comparación con un testigo obtenido sin esta formulación enzimática. El proceso se ha realizado en biorreactores con microorganismos inmovilizados en dos soportes micronizados arcillosos, Sepiolita y Bentonita. A partir de los datos volumen de metano-tiempo, se calculan las constantes específicas de velocidad, Ko, utilizando la ecuación de Roediger. Dentro del rango de concentración de sustrato estudiado se observa una disminución de la constante cinética al aumentar el volumen de residuo añadido a los digestores lo que confirma la existencia de un proceso de inhibición, que es más acusado en el caso del alpechín obtenido con Olivex. Para determinar las constantes de inhibición del proceso se utiliza el modelo propuesto por Levenspiel.

  20. Aislamiento de hongos solubilizadores de fosfatos de la rizósfera de Arazá (Eugenia stipitata, Myrtaceae Isolation of phosphate solubilizer fungi from Araza rhizosphere

    Directory of Open Access Journals (Sweden)

    Valencia Hernando

    2002-06-01

    Full Text Available Arazá (Eugenia stipitataMcVaugh, es una planta originaria de la región amazónica,que ha sido descrita como especie promisoria ya que su fruto comestible presentaexcelentes posibilidades de comercialización (Quevedo, 1995. El frutal muestra unaelevada productividad aún en suelos con muy bajo contenido de fósforo. La presenciade microorganismos solubilizadores de fosfatos podría contribuir a aumentar la dispo-nibilidad de este macroelemento. Dado que no se han publicado estudios al respecto,durante esta investigación se realizó el aislamiento y la caracterización de hongos so-lubilizadores a partir de 12 muestras de suelo en cultivos de Arazá, procedentes de 2Unidades Fisiográficas (paisajes del departamento del Guaviare (Colombia, utilizandoel método de lavado de suelo. Se obtuvieron 18 aislamientos de hongos a partir de1.152 agregados de suelo, los cuales demostraron capacidad de solubilizar fosfato nodisponible, procedente de 2 fuentes diferentes (hidrogenofosfato de calcio y fosfato dehierro III hidratados. Los principales solubilizadores del fosfato de calcio fueron Trichodermaaureoviride, Aspergillus aculeatus, Trichodermacepa 1 y Trichodermacepa 2 y para el fosfatode hierro: Aspergillus oryzae, Paecilomycescepa 3, Gongronella butleriy Fusarium oxysporum.Araza is an eatable plant, original from the Amazon region which has been describedas a promising species for commercialization (Quevedo 1995. This plant has highproductivity even in low content phosphate soil but the presence of phosphatesolubilizazing microorganisms may contribute to increase this element availability.In this study we report the isolation and characterization of solubilizing fungiprocessed using the soil washing method, from soil samples were Araza is cultivated attwo regions in Guaviare, Colombia. Eighteen isolates of fungi capable of solubilizingphosphate were obtained from 2 different sources. The most importat species that solubilized phosphate from

  1. Mate choice, sexual imprinting, and speciation: a test of a one-allele isolating mechanism in sympatric sticklebacks.

    Science.gov (United States)

    Albert, Arianne Y K

    2005-04-01

    One-allele isolating mechanisms should make the evolution of reproductive isolation between potentially hybridizing taxa easier than two-allele mechanisms, but the generality of one-allele mechanisms in nature has yet to be established. A potentially important one-allele mechanism is sexual imprinting, where the mate preferences of individuals are based on the phenotype of their parents. Here I test the possibility that sexual imprinting promotes reproductive isolation using sympatric species of threespine sticklebacks (Gasterosteus aculeatus). Sympatric species of sticklebacks consist of large benthic species and small limnetic species that are reproductively isolated and adapted to feeding in different environments. I fostered families of F1 hybrids between the species to males of both species. Preferences of these fostered females for males of either type revealed little or no effect of sexual imprinting on assortative mating. However, F1 females showed preferences for males that were similar to themselves in length, suggesting that size-assortative mating may be more important than sexual imprinting for promoting reproductive isolation between species pairs of threespine sticklebacks.

  2. Slow fertilization of stickleback eggs: the result of sexual conflict?

    Science.gov (United States)

    Bakker, Theo C M; Zbinden, Marc; Frommen, Joachim G; Weiss, Alexander; Largiadèr, Carlo R

    2006-05-19

    The fertilization success in sperm competition in externally fertilizing fish depends on number and quality of sperm. The time delay between sequential ejaculations may further influence the outcome of sperm competition. Such a time interval can load the raffle over fertilization if fertilization takes place very fast. Short fertilization times are generally assumed for externally fertilizing fish such as the three-spined stickleback (Gasterosteus aculeatus). In this pair-spawning fish, territorial males often try to steal fertilizations in nests of neighbouring males. This sneaking behaviour causes sperm competition. Sneakers will only get a share of paternity when eggs are not fertilized immediately after sperm release. Contrary to males, females may be interested in multiple paternity of their clutch of eggs. There thus may be a sexual conflict over the speed of fertilization. In this study we used two different in vitro fertilization experiments to assess how fast eggs are fertilized in sticklebacks. We show that complete fertilization takes more than 5 min which is atypically long for externally fertilizing fishes. This result suggests that the time difference does not imply high costs to the second stickleback male to ejaculate. Slow fertilization (and concomitant prolonged longevity of sperm) may be the result of sexual conflict in which females aimed at complete fertilization and/or multiple paternity.

  3. Nutritional state influences shoaling preference for familiars.

    Science.gov (United States)

    Frommen, Joachim G; Luz, Corinna; Bakker, Theo C M

    2007-01-01

    Preferences for grouping with familiar individuals are shown in many animal species, including the three-spined stickleback (Gasterosteus aculeatus). Shoaling with familiars is advantageous because of more precise anti-predator behaviours or more stable dominance hierarchies. Additionally, associations with familiar individuals facilitate the evolution of altruistic behaviour. Thus, in situations of increased competition one might expect an increased preference for familiar fish. We gave single juvenile sticklebacks of different nutritional state the choice between shoals composed either of familiar or unfamiliar individuals. Satiated fish preferred to shoal with familiar individuals. A comparative analysis of 8 stickleback studies with 15 different tests using familiars showed that all tests gave similar results, i.e. sticklebacks of all age classes preferred to shoal with familiars in a non-sexual context. In contrast, hungry test fish did not prefer to shoal with familiar fish, but even showed a preference for the unfamiliar group. Because sticklebacks use early-life familiarity to recognize kin, the results suggest the avoidance of competition with relatives. To our knowledge, this is the first study showing an impact of nutritional state on social interactions with familiar individuals.

  4. Slow fertilization of stickleback eggs: the result of sexual conflict?

    Directory of Open Access Journals (Sweden)

    Frommen Joachim G

    2006-05-01

    Full Text Available Abstract Background The fertilization success in sperm competition in externally fertilizing fish depends on number and quality of sperm. The time delay between sequential ejaculations may further influence the outcome of sperm competition. Such a time interval can load the raffle over fertilization if fertilization takes place very fast. Short fertilization times are generally assumed for externally fertilizing fish such as the three-spined stickleback (Gasterosteus aculeatus. In this pair-spawning fish, territorial males often try to steal fertilizations in nests of neighbouring males. This sneaking behaviour causes sperm competition. Sneakers will only get a share of paternity when eggs are not fertilized immediately after sperm release. Contrary to males, females may be interested in multiple paternity of their clutch of eggs. There thus may be a sexual conflict over the speed of fertilization. Results In this study we used two different in vitro fertilization experiments to assess how fast eggs are fertilized in sticklebacks. We show that complete fertilization takes more than 5 min which is atypically long for externally fertilizing fishes. Conclusion This result suggests that the time difference does not imply high costs to the second stickleback male to ejaculate. Slow fertilization (and concomitant prolonged longevity of sperm may be the result of sexual conflict in which females aimed at complete fertilization and/or multiple paternity.

  5. Quantification acuity in spontaneous shoaling decisions of three-spined sticklebacks.

    Science.gov (United States)

    Mehlis, Marion; Thünken, Timo; Bakker, Theo C M; Frommen, Joachim G

    2015-09-01

    The ability to discriminate between different quantities is widespread throughout the animal kingdom, and the underlying mechanisms of quantity discrimination are currently intensely discussed. In contrast, questions elucidating the limits of quantity estimation received rather little attention so far. Here, we examined fine-tuned quantity estimation in the three-spined stickleback (Gasterosteus aculeatus) in a natural context, i.e. during shoaling decisions. Wild-caught focal fish were given the spontaneous choice between two shoals which differed in group size by 1 fish (0 vs. 1, 1 vs. 2, 2 vs. 3, 3 vs. 4, 4 vs. 5, 5 vs. 6 and 6 vs. 7), based on visual assessment. The results show that sticklebacks generally prefer to shoal with the larger group. They discriminated numerical contrasts up to 6 versus 7, equalling a numerical ratio of 0.86. Preference patterns followed Weber's law, i.e. decreased with increasing numerical ratio. This pattern was found across all numerical conditions as well as within the small number range (ranging from 1 vs. 2 to 3 vs. 4). The results suggest that wild-caught three-spined sticklebacks are spontaneously able (i.e. without prior learning) to detect subtle differences in shoal sizes. Further, they confirm findings of previous studies highlighting the contribution of the analogue magnitude system to quantity estimation in fishes.

  6. Identification and characterization of an acidic and acid-stable endoxyloglucanase from Penicillium oxalicum.

    Science.gov (United States)

    Xian, Liang; Wang, Fei; Yin, Xin; Feng, Jia-Xun

    2016-05-01

    Xyloglucan is a major structural macromolecule of the primary cell wall of spermatophytes. The hydrolysis of xyloglucan by xyloglucanases may facilitate the hydrolysis of cellulose by cellulases, which is beneficial for bioethanol production. Penicillium oxalicum has been employed for commercial cellulase production. In P. oxalicum, many genes and proteins related to the degradation of structural macromolecules of the plant cell wall have been found, but no gene encoding a xyloglucanase has been identified. In this study, a gene, PoxXEG12A, was cloned from P. oxalicum and expressed in Pichia pastoris, and the gene product was enzymatically characterized. PoxXEG12A shared 63% sequence identity with endoxyloglucanases from Aspergillus niger and Aspergillus aculeatus. PoxXEG12A specifically hydrolyzed tamarind xyloglucan in endo-acting mode and, thus, it is an endoxyloglucanase. PoxXEG12A was most active at pH 4.5-5.5 and at 55-60 °C, with a specific activity of 172 U/mg protein toward tamarind xyloglucan. The enzyme was stable at pH 3.5-7.0 and below 40 °C. The properties of the endoxyloglucanase PoxXEG12A suggest that the enzyme might have potential in industrial applications.

  7. A RAD-tag genetic map for the platyfish (Xiphophorus maculatus) reveals mechanisms of karyotype evolution among teleost fish.

    Science.gov (United States)

    Amores, Angel; Catchen, Julian; Nanda, Indrajit; Warren, Wesley; Walter, Ron; Schartl, Manfred; Postlethwait, John H

    2014-06-01

    Mammalian genomes can vary substantially in haploid chromosome number even within a small taxon (e.g., 3-40 among deer alone); in contrast, teleost fish genomes are stable (24-25 in 58% of teleosts), but we do not yet understand the mechanisms that account for differences in karyotype stability. Among perciform teleosts, platyfish (Xiphophorus maculatus) and medaka (Oryzias latipes) both have 24 chromosome pairs, but threespine stickleback (Gasterosteus aculeatus) and green pufferfish (Tetraodon nigroviridis) have just 21 pairs. To understand the evolution of teleost genomes, we made a platyfish meiotic map containing 16,114 mapped markers scored on 267 backcross fish. We tiled genomic contigs along the map to create chromosome-length genome assemblies. Genome-wide comparisons of conserved synteny showed that platyfish and medaka karyotypes remained remarkably similar with few interchromosomal translocations but with numerous intrachromosomal rearrangements (transpositions and inversions) since their lineages diverged ∼120 million years ago. Comparative genomics with platyfish shows how reduced chromosome numbers in stickleback and green pufferfish arose by fusion of pairs of ancestral chromosomes after their lineages diverged from platyfish ∼195 million years ago. Zebrafish and human genomes provide outgroups to root observed changes. These studies identify likely genome assembly errors, characterize chromosome fusion events, distinguish lineage-independent chromosome fusions, show that the teleost genome duplication does not appear to have accelerated the rate of translocations, and reveal the stability of syntenies and gene orders in teleost chromosomes over hundreds of millions of years.

  8. Parallel genetic basis for repeated evolution of armor loss in Alaskan threespine stickleback populations.

    Science.gov (United States)

    Cresko, William A; Amores, Angel; Wilson, Catherine; Murphy, Joy; Currey, Mark; Phillips, Patrick; Bell, Michael A; Kimmel, Charles B; Postlethwait, John H

    2004-04-20

    Most adaptation is thought to occur through the fixation of numerous alleles at many different loci. Consequently, the independent evolution of similar phenotypes is predicted to occur through different genetic mechanisms. The genetic basis of adaptation is still largely unknown, however, and it is unclear whether adaptation to new environments utilizes ubiquitous small-effect polygenic variation or large-effect alleles at a small number of loci. To address this question, we examined the genetic basis of bony armor loss in three freshwater populations of Alaskan threespine stickleback, Gasterosteus aculeatus, that evolved from fully armored anadromous populations in the last 14,000 years. Crosses between complete-armor and low-armor populations revealed that a single Mendelian factor governed the formation of all but the most anterior lateral plates, and another independently segregating factor largely determined pelvic armor. Genetic mapping localized the Mendelian genes to different chromosomal regions, and crosses among these same three widely separated populations showed that both bony plates and pelvic armor failed to fully complement, implicating the same Mendelian armor reduction genes. Thus, rapid and repeated armor loss in Alaskan stickleback populations appears to be occurring through the fixation of large-effect variants in the same genes.

  9. Developmental genetic basis for the evolution of pelvic fin loss in the pufferfish Takifugu rubripes.

    Science.gov (United States)

    Tanaka, Mikiko; Hale, Laura A; Amores, Angel; Yan, Yi-Lin; Cresko, William A; Suzuki, Tohru; Postlethwait, John H

    2005-05-15

    Paired appendages were a key developmental innovation among vertebrates and they eventually evolved into limbs. Ancient developmental control systems for paired fins and limbs are broadly conserved among gnathostome vertebrates. Some lineages including whales, some salamanders, snakes, and many ray-fin fish, independently lost the pectoral, pelvic, or both appendages over evolutionary time. When different taxa independently evolve similar developmental morphologies, do they use the same molecular genetic mechanisms? To determine the developmental genetic basis for the evolution of pelvis loss in the pufferfish Takifugu rubripes (fugu), we isolated fugu orthologs of genes thought to be essential for limb development in tetrapods, including limb positioning (Hoxc6, Hoxd9), limb bud initiation (Pitx1, Tbx4, Tbx5), and limb bud outgrowth (Shh, Fgf10), and studied their expression patterns during fugu development. Results showed that bud outgrowth and initiation fail to occur in fugu, and that pelvis loss is associated with altered expression of Hoxd9a, which we show to be a marker for pelvic fin position in three-spine stickleback Gasterosteus aculeatus. These results rule out changes in appendage outgrowth and initiation genes as the earliest developmental defect in pufferfish pelvic fin loss and suggest that altered Hoxd9a expression in the lateral mesoderm may account for pelvis loss in fugu. This mechanism appears to be different from the mechanism for pelvic loss in stickleback, showing that different taxa can evolve similar phenotypes by different mechanisms.

  10. Duplication and divergence of fgf8 functions in teleost development and evolution.

    Science.gov (United States)

    Jovelin, Richard; He, Xinjun; Amores, Angel; Yan, Yi-Lin; Shi, Ruihua; Qin, Baifang; Roe, Bruce; Cresko, William A; Postlethwait, John H

    2007-12-15

    Fibroblast growth factors play critical roles in many aspects of embryo patterning that are conserved across broad phylogenetic distances. To help understand the evolution of fibroblast growth factor functions, we identified members of the Fgf8/17/18-subfamily in the three-spine stickleback Gasterosteus aculeatus, and investigated their evolutionary relationships and expression patterns. We found that fgf17b is the ortholog of tetrapod Fgf17, whereas the teleost genes called fgf8 and fgf17a are duplicates of the tetrapod gene Fgf8, and thus should be called fgf8a and fgf8b. Phylogenetic analysis supports the view that the Fgf8/17/18-subfamily expanded during the ray-fin fish genome duplication. In situ hybridization experiments showed that stickleback fgf8 duplicates exhibited common and unique expression patterns, indicating that tissue specialization followed the gene duplication event. Moreover, direct comparison of stickleback and zebrafish embryonic expression patterns of fgf8 co-orthologs suggested lineage-specific independent subfunction partitioning and the acquisition or the loss of ortholog functions. In tetrapods, Fgf8 plays an important role in the apical ectodermal ridge of the developing pectoral appendage. Surprisingly, differences in the expression of fgf8a in the apical ectodermal ridge of the pectoral fin bud in zebrafish and stickleback, coupled with the role of fgf16 and fgf24 in teleost pectoral appendage show that different Fgf genes may play similar roles in limb development in various vertebrates.

  11. Construction of the High-Density Genetic Linkage Map and Chromosome Map of Large Yellow Croaker (Larimichthys crocea

    Directory of Open Access Journals (Sweden)

    Jingqun Ao

    2015-11-01

    Full Text Available High-density genetic maps are essential for genome assembly, comparative genomic analysis and fine mapping of complex traits. In this study, 31,191 single nucleotide polymorphisms (SNPs evenly distributed across the large yellow croaker (Larimichthys crocea genome were identified using restriction-site associated DNA sequencing (RAD-seq. Among them, 10,150 high-confidence SNPs were assigned to 24 consensus linkage groups (LGs. The total length of the genetic linkage map was 5451.3 cM with an average distance of 0.54 cM between loci. This represents the densest genetic map currently reported for large yellow croaker. Using 2889 SNPs to target specific scaffolds, we assigned 533 scaffolds, comprising 421.44 Mb (62.04% of the large yellow croaker assembled sequence, to the 24 linkage groups. The mapped assembly scaffolds in large yellow croaker were used for genome synteny analyses against the stickleback (Gasterosteus aculeatus and medaka (Oryzias latipes. Greater synteny was observed between large yellow croaker and stickleback. This supports the hypothesis that large yellow croaker is more closely related to stickleback than to medaka. Moreover, 1274 immunity-related genes and 195 hypoxia-related genes were mapped to the 24 chromosomes of large yellow croaker. The integration of the high-resolution genetic map and the assembled sequence provides a valuable resource for fine mapping and positional cloning of quantitative trait loci associated with economically important traits in large yellow croaker.

  12. A high performance Trichoderma reesei strain that reveals the importance of xylanase III in cellulosic biomass conversion.

    Science.gov (United States)

    Nakazawa, Hikaru; Kawai, Tetsushi; Ida, Noriko; Shida, Yosuke; Shioya, Kouki; Kobayashi, Yoshinori; Okada, Hirofumi; Tani, Shuji; Sumitani, Jun-ichi; Kawaguchi, Takashi; Morikawa, Yasushi; Ogasawara, Wataru

    2016-01-01

    The ability of the Trichoderma reesei X3AB1strain enzyme preparations to convert cellulosic biomass into fermentable sugars is enhanced by the replacement of xyn3 by Aspergillus aculeatus β-glucosidase 1 gene (aabg1), as shown in our previous study. However, subsequent experiments using T. reesei extracts supplemented with the glycoside hydrolase (GH) family 10 xylanase III (XYN III) and GH Family 11 XYN II showed increased conversion of alkaline treated cellulosic biomass, which is rich in xylan, underscoring the importance of XYN III. To attain optimal saccharifying potential in T. reesei, we constructed two new strains, C1AB1 and E1AB1, in which aabg1 was expressed heterologously by means of the cbh1 or egl1 promoters, respectively, so that the endogenous XYN III synthesis remained intact. Due to the presence of wild-type xyn3 in T. reesei E1AB1, enzymes prepared from this strain were 20-30% more effective in the saccharification of alkaline-pretreated rice straw than enzyme extracts from X3AB1, and also outperformed recent commercial cellulase preparations. Our results demonstrate the importance of XYN III in the conversion of alkaline-pretreated cellulosic biomass by T. reesei.

  13. A Comparative BAC map for the gilthead sea bream (Sparus aurata L.).

    Science.gov (United States)

    Kuhl, Heiner; Sarropoulou, Elena; Tine, Mbaye; Kotoulas, Georgios; Magoulas, Antonios; Reinhardt, Richard

    2011-01-01

    This study presents the first comparative BAC map of the gilthead sea bream (Sparus aurata), a highly valuated marine aquaculture fish species in the Mediterranean. High-throughput end sequencing of a BAC library yielded 92,468 reads (60.6  Mbp). Comparative mapping was achieved by anchoring BAC end sequences to the three-spined stickleback (Gasterosteus aculeatus) genome. BACs that were consistently ordered along the stickleback chromosomes accounted for 14,265 clones. A fraction of 5,249 BACs constituted a minimal tiling path that covers 73.5% of the stickleback chromosomes and 70.2% of the genes that have been annotated. The N50 size of 1,485 "BACtigs" consisting of redundant BACs is 337,253 bp. The largest BACtig covers 2.15 Mbp in the stickleback genome. According to the insert size distribution of mapped BACs the sea bream genome is 1.71-fold larger than the stickleback genome. These results represent a valuable tool to researchers in the field and may support future projects to elucidate the whole sea bream genome.

  14. To eat or not to eat: egg-based assessment of paternity triggers fine-tuned decisions about filial cannibalism.

    Science.gov (United States)

    Mehlis, Marion; Bakker, Theo C M; Engqvist, Leif; Frommen, Joachim G

    2010-09-07

    Filial cannibalism occurs in many animal species ranging from insects to mammals, and is especially well described in teleost fishes. Numerous causes may lead to this behaviour, e.g. certainty of paternity. However, the cues males use to assess their paternity often remain unknown. One possible way to differentiate between own and foreign offspring is by using egg cues. Nevertheless, in egg-laying species, evidence for this is still scarce. In this study, male three-spined sticklebacks (Gasterosteus aculeatus), a fish with paternal care in which sneaking as well as filial cannibalism is common, were allowed to care for manipulated nests that contained different percentages of own fertilized eggs. After 7 days, embryo survival was determined. Furthermore, brood-caring as well as aggressive behaviour was measured daily. Clutches containing a higher proportion of foreign eggs were more likely to be completely cannibalized than clutches containing a lower proportion of foreign eggs, particularly when the clutch was laid early in the breeding season. However, the behavioural observations revealed no influence of paternity. The results show that paternity triggers filial cannibalism in sticklebacks and that males are able to evaluate their paternity using egg cues alone.

  15. Puesta a punto del método de PCR en tiempo real para la cuantificación de Aspergillus carbonarius en uvas Vitis vinifera cv. Tannat

    Directory of Open Access Journals (Sweden)

    Gustavo Garmendia

    2011-12-01

    Full Text Available La ocratoxina A (OTA es una micotoxina que ha sido detectada en uvas y vinos. Es producida por Aspergillus ochraceus, Penicillium verrucosum, Aspergillus carbonarius y especies pertenecientes al agregado Aspergillus niger. En los últimos años se ha descrito la presencia de Aspergillus aculeatus y Aspergillus japonicus en la superficie de uvas y su capacidad de producir OTA. A pesar de que la concentración detectada de cepas pertenecientes a la Sección Nigri fue < 100/g de uva, se han aislado, identificado y caracterizado 56 cepas de Aspergillus pertenecientes a la Sección Nigri. El 51 % fue identificado como A. niger, el 39 % como A. japonicus, 5 % como A. tubingensis -like y 5 % como A. foetidus. Ninguna cepa de A. carbonarius fue aislada. Debido a que esta especie ha sido descrita como la principal responsable de la presencia de OTA en uvas y vinos por su capacidad de producir altas concentraciones de OTA, se requiere un método más sensible que los métodos convencionales para detectar y cuantificar la presencia de A. carbonarius en uva. En este trabajo se optimizó la técnica de PCR en tiempo real para la detección y cuantificación de esta especie en uvas d e la variedad Tannat.

  16. Use of seasonal freshwater wetlands by fishes in a temperate river floodplain

    Science.gov (United States)

    Henning, Julie A.; Gresswell, Robert E.; Fleming, Ian A.

    2007-01-01

    This study examined the use of freshwater wetland restoration and enhancement projects (i.e. non-estuarine wetlands subject to seasonal drying) by fish populations. To quantify fish use of freshwater emergent wetlands and assess the effect of wetland enhancement (i.e. addition of water control structures), two enhanced and two unenhanced emergent wetlands were compared, as well as two oxbow habitats within the Chehalis River floodplain. Eighteen fish species were captured using fyke nets and emigrant traps from January to the beginning of June, with the most abundant being three-spined stickleback Gasterosteus aculeatus and Olympic mudminnow Novumbra hubbsi. Coho salmon Oncorhynchus kisutch was the dominant salmonid at all sites. Enhanced wetlands, with their extended hydroperiods, had significantly higher abundances of yearling coho salmon than unenhanced wetlands. Both enhanced and unenhanced emergent wetlands yielded higher abundances of non-game native fishes than oxbow habitats. Oxbow habitats, however, were dominated by coho salmon. Fish survival in the wetland habitats was dependent on emigration to the river before dissolved oxygen concentrations decreased and wetlands became isolated and stranding occurred. This study suggests that wetland enhancement projects with an outlet to the river channel appear to provide fishes with important temporary habitats if they have the opportunity to leave the wetland as dissolved oxygen levels deteriorate.

  17. Antimicrobial activity of 20 plants used in folkloric medicine in the Palestinian area.

    Science.gov (United States)

    Ali-Shtayeh, M S; Yaghmour, R M; Faidi, Y R; Salem, K; Al-Nuri, M A

    1998-04-01

    Ethanolic and aqueous extracts of 20 Palestinian plant species used in folk medicine were investigated for their antimicrobial activities against five bacterial species (Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris, Pseudomonas aeruginosa) and one yeast (Candida albicans). The plants showed 90% of antimicrobial activity, with significant difference in activity between the different plants. The most antimicrobially active plants were Phagnalon rupestre and Micromeria nervosa, whereas, the least active plant was Ziziphus spina-christi. Only ten of the tested plant extracts were active against C. albicans, with the most active from M. nervosa and Inula viscosa and the least active from Ruscus aculeatus. Of all extracts the ethanolic extract of M. nervosa was the most active, whereas, the aqueous extract of Phagnalon rupestre was the most active of all aqueous extracts tested. The ethanolic extracts (70%) showed activity against both Gram positive and negative bacteria and 40% of these extracts showed anticandidal activity, whereas, 50% of the aqueous extracts showed antibacterial activity and 20% of these extracts showed anticandidal activity.

  18. Antifungal activity of plant extracts against dermatophytes.

    Science.gov (United States)

    Ali-Shtayeh, M S; Abu Ghdeib, S I

    1999-01-01

    The aqueous extracts (15 micrograms ml-1 medium) of 22 plants used in folkloric medicine in Palestine were investigated for their antifungal activity and minimum inhibitory concentrations (MICs) against nine isolates of Microsporum canis, Trichophyton mentagrophytes and Trichophyton violaceum. The extract of the different plant species reduced colony growth of the three dermatophytes by 36 to 100% compared with the control treatment. Antimycotic activity of the extract against the three dermatophytes varied significantly (P Inula viscosa, J. regia and P. lentiscus against T. mentagrophytes; and Asphodelus luteus, A. arvensis, C. spinosa, Clematis cirrhosa, I. viscosa, J. regia, P. lentiscus, Plumbago europea, Ruscus aculeatus, Retema raetam and Salvia fruticosa against T. violaceum. The MICs of these most active plants ranged from 0.6 to 40 micrograms ml-1. The three dermatophytes differed significantly with regard to their susceptibility to plant extracts. Trichophyton violaceum was the most susceptible being completely inhibited by 50% of the extracts followed by M. canis and T. mentagrophytes which were completely inhibited by only 23 and 14% of the extracts, respectively.

  19. Influence of physical and chemical characteristics of wine grapes on the incidence of Penicillium and Aspergillus fungi in grapes and ochratoxin A in wines.

    Science.gov (United States)

    Freire, Luísa; Passamani, Fabiana Reinis Franca; Thomas, Ariela Betsy; Nassur, Rita de Cássia Mirela Resende; Silva, Lais Mesquita; Paschoal, Fabiano Narciso; Pereira, Giuliano Elias; Prado, Guilherme; Batista, Luís Roberto

    2017-01-16

    The incidence of filamentous fungi and toxin levels in grapes and wines varies depending on the variety of grapes, the wine region, agricultural practices, weather conditions, the harvest and the winemaking process. In this sense, the objective of this study was to evaluate the diversity of Aspergillus and Penicillium fungi isolated from wine grapes of the semi-arid tropical region of Brazil, evaluate the presence of ochratoxin A (OTA) in the experimental wine and verify if there is a correlation between occurrence of these fungi and the physicochemical characteristics of the wine grapes grown in the region. For the isolation of fungi we used the direct plating technique. The presence of OTA in the experimental wine was detected by high-performance liquid chromatography. The species found were Aspergillus niger, A. carbonarius, A. aculeatus, A. niger Aggregate, A. flavus, A. sojae, Penicillium sclerotiorum, P. citrinum, P. glabrum, P. decumbens, P. solitum and P. implicatum. All isolates of A. carbonarius were OTA producers and all P. citrinum were citrinin producers. The highest concentration of OTA was found in red wine (0.29μg/L). All species identified in this study, except A. flavus, showed a positive correlation with at least one physicochemical parameter assessed, highlighting the pectin content, total sugar, total acidity and phenolic compounds. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. 章鱼用双“脚”行走

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    章鱼可以说是欺骗大师。它们能够变换自身的形状和颜色来适应周围的环境,有些章鱼甚至能够模仿其他的海洋生物。美国加州大学伯克利分校的研究生克里斯廷‘赫法德(Christine Huffard)表示,这也许就是为什么Octopus aculeatus 章鱼的行为令人着迷的原因。这个家伙能够利用两只触手的尖端在海底上碎步疾行——在这一连串的动作中,章鱼的“脚”能够交替前进,这不免让人惊讶地联想起人类的行走——与此同时,它的另外6只触手则向外伸出,看起来就像是一团漂浮的海藻。

  1. Identifying and characterizing the most significant β-glucosidase of the novel species Aspergillus saccharolyticus

    Energy Technology Data Exchange (ETDEWEB)

    Sorensen, Anette; Ahring, Birgitte K.; Lubeck, Mette; Ubhayasekera, Wimal; Bruno, Kenneth S.; Culley, David E.; Lubeck, Peter S.

    2012-08-20

    A newly discovered fungal species, Aspergillus saccharolyticus, was found to produce a culture broth rich in beta-glucosidase activity. In this present work, the main beta-glucosidase of A. saccharolyticus responsible for the efficient hydrolytic activity was identified, isolated, and characterized. Ion exchange chromatography was used to fractionate the culture broth, yielding fractions with high beta-glucosidase activity and only one visible band on an SDS-PAGE gel. Mass spectrometry analysis of this band gave peptide matches to beta-glucosidases from aspergilli. Through a PCR approach using degenerate primers and genome walking, a 2919 base pair sequence encoding the 860 amino acid BGL1 polypeptide was determined. BGL1 of A. saccharolyticus has 91% and 82% identity with BGL1 from Aspergillus aculeatus and BGL1 from Aspergillus niger, respectively, both belonging to Glycoside hydrolase family 3. Homology modeling studies suggested beta-glucosidase activity with preserved retaining mechanism and a wider catalytic pocket compared to other beta-glucosidases. The bgl1 gene was heterologously expressed in Trichoderma reesei QM6a, purified, and characterized by enzyme kinetics studies. The enzyme can hydrolyze cellobiose, pNPG, and cellodextrins. The enzyme showed good thermostability, was stable at 50°C, and at 60°C it had a half-life of approximately 6 hours.

  2. Cloning and Genomic Organization of a Rhamnogalacturonase Gene from Locally Isolated Strain of Aspergillus niger.

    Science.gov (United States)

    Damak, Naourez; Abdeljalil, Salma; Taeib, Noomen Hadj; Gargouri, Ali

    2015-08-01

    The rhg gene encoding a rhamnogalacturonase was isolated from the novel strain A1 of Aspergillus niger. It consists of an ORF of 1.505 kb encoding a putative protein of 446 amino acids with a predicted molecular mass of 47 kDa, belonging to the family 28 of glycosyl hydrolases. The nature and position of amino acids comprising the active site as well as the three-dimensional structure were well conserved between the A. niger CTM10548 and fungal rhamnogalacturonases. The coding region of the rhg gene is interrupted by three short introns of 56 (introns 1 and 3) and 52 (intron 2) bp in length. The comparison of the peptide sequence with A. niger rhg sequences revealed that the A1 rhg should be an endo-rhamnogalacturonases, more homologous to rhg A than rhg B A. niger known enzymes. The comparison of rhg nucleotide sequence from A. niger A1 with rhg A from A. niger shows several base changes. Most of these changes (59 %) are located at the third base of codons suggesting maintaining the same enzyme function. We used the rhamnogalacturonase A from Aspergillus aculeatus as a template to build a structural model of rhg A1 that adopted a right-handed parallel β-helix.

  3. New parasites and predators follow the introduction of two fish species to a subarctic lake: implications for food-web structure and functioning

    Science.gov (United States)

    Amundsen, Per-Arne; Lafferty, Kevin D.; Knudsen, Rune; Primicerio, Raul; Kristoffersen, Roar; Klemetsen, Anders; Kuris, Armand M.

    2012-01-01

    Introduced species can alter the topology of food webs. For instance, an introduction can aid the arrival of free-living consumers using the new species as a resource, while new parasites may also arrive with the introduced species. Food-web responses to species additions can thus be far more complex than anticipated. In a subarctic pelagic food web with free-living and parasitic species, two fish species (arctic charr Salvelinus alpinus and three-spined stickleback Gasterosteus aculeatus) have known histories as deliberate introductions. The effects of these introductions on the food web were explored by comparing the current pelagic web with a heuristic reconstruction of the pre-introduction web. Extinctions caused by these introductions could not be evaluated by this approach. The introduced fish species have become important hubs in the trophic network, interacting with numerous parasites, predators and prey. In particular, five parasite species and four predatory bird species depend on the two introduced species as obligate trophic resources in the pelagic web and could therefore not have been present in the pre-introduction network. The presence of the two introduced fish species and the arrival of their associated parasites and predators increased biodiversity, mean trophic level, linkage density, and nestedness; altering both the network structure and functioning of the pelagic web. Parasites, in particular trophically transmitted species, had a prominent role in the network alterations that followed the introductions.

  4. Environmental temperature variation influences fitness trade-offs and tolerance in a fish-tapeworm association.

    Science.gov (United States)

    Franke, Frederik; Armitage, Sophie A O; Kutzer, Megan A M; Kurtz, Joachim; Scharsack, Jörn P

    2017-06-02

    Increasing temperatures are predicted to strongly impact host-parasite interactions, but empirical tests are rare. Host species that are naturally exposed to a broad temperature spectrum offer the possibility to investigate the effects of elevated temperatures on hosts and parasites. Using three-spined sticklebacks, Gasterosteus aculeatus L., and tapeworms, Schistocephalus solidus (Müller, 1776), originating from a cold and a warm water site of a volcanic lake, we subjected sympatric and allopatric host-parasite combinations to cold and warm conditions in a fully crossed design. We predicted that warm temperatures would promote the development of the parasites, while the hosts might benefit from cooler temperatures. We further expected adaptations to the local temperature and mutual adaptations of local host-parasite pairs. Overall, S. solidus parasites grew faster at warm temperatures and stickleback hosts at cold temperatures. On a finer scale, we observed that parasites were able to exploit their hosts more efficiently at the parasite's temperature of origin. In contrast, host tolerance towards parasite infection was higher when sticklebacks were infected with parasites at the parasite's 'foreign' temperature. Cold-origin sticklebacks tended to grow faster and parasite infection induced a stronger immune response. Our results suggest that increasing environmental temperatures promote the parasite rather than the host and that host tolerance is dependent on the interaction between parasite infection and temperature. Sticklebacks might use tolerance mechanisms towards parasite infection in combination with their high plasticity towards temperature changes to cope with increasing parasite infection pressures and rising temperatures.

  5. Diversity and abundance of water birds in a subarctic lake during three decades

    Directory of Open Access Journals (Sweden)

    Anders Klemetsen

    2013-12-01

    Full Text Available The numbers of divers, ducks, gulls, terns and waders in the 15 km2 oligotrophic lake Takvatn, North Norway were estimated six times during 1983-2012. Systematic mapping surveys were done by boat within the first week after ice-break in June. Twenty-one species were observed over the years and 12 were regarded as breeding on the lake. Red-breasted merganser Mergus serrator was the dominant diving bird, with estimated minimum number of pairs varying from 15 to 39 among years. Black-throated diver Gavia arctica (1-3 pairs, tufted duck Aythya fuligula (2-15 pairs and common scoter Melanitta nigra (1-5 pairs bred regularly, while velvet scoter Melanitta fusca (1-2 and goldeneye Bucephala clangula (2-4 were found in some years and mallard Anas platyrhynchos (1 pair and wigeon Anas penelope (1 pair in one year. Common gull Larus canus (6-30 pairs and arctic tern Sterna paradisaea (2-35 pairs bred in all years. Common sandpiper Tringa hypoleucos (3-9 pairs and redshank Tringa totanus (1-4 pairs were regular waders. Density variations of mergansers, gulls and terns are possibly related to density variations of three-spined sticklebacks Gasterosteus aculeatus, their dominant fish prey. The water birds are important links in the food web of the lake.

  6. Information flow through threespine stickleback networks without social transmission

    Science.gov (United States)

    Atton, N.; Hoppitt, W.; Webster, M. M.; Galef, B. G.; Laland, K. N.

    2012-01-01

    Social networks can result in directed social transmission of learned information, thus influencing how innovations spread through populations. Here we presented shoals of threespine sticklebacks (Gasterosteous aculeatus) with two identical foraging tasks and applied network-based diffusion analysis (NBDA) to determine whether the order in which individuals in a social group contacted and solved the tasks was affected by the group's network structure. We found strong evidence for a social effect on discovery of the foraging tasks with individuals tending to discover a task sooner when others in their group had previously done so, and with the spread of discovery of the foraging tasks influenced by groups' social networks. However, the same patterns of association did not reliably predict spread of solution to the tasks, suggesting that social interactions affected the time at which the tasks were discovered, but not the latency to its solution following discovery. The present analysis, one of the first applications of NBDA to a natural animal system, illustrates how NBDA can lead to insight into the mechanisms supporting behaviour acquisition that more conventional statistical approaches might miss. Importantly, we provide the first compelling evidence that the spread of novel behaviours can result from social learning in the absence of social transmission, a phenomenon that we refer to as an untransmitted social effect on learning. PMID:22896644

  7. Comparison of catching efficiency of two Indonesian traditional traps, Ayunan and Tamba

    Directory of Open Access Journals (Sweden)

    Ahmadi

    2014-08-01

    Full Text Available The catching efficiency of traditional traps: Ayunan and Tamba were tested in Sungai Batang River, South Kalimantan of Indonesia. Trials consisted of 320-trap hauls/type using 1-day submersion time of 24 hr. The baited traps sampling accounted for 82 specimens assigned to 5 species of 5 families. There was a large variability in number of catch between prawns and fish species collected (T=2.318, P<0.05. The prawns catch was represented by only the species Macrobrachium rossenbergii with total of 53 and 1,015 g weight. The prawns weight of Tamba was significantly higher than that of Ayunan (T=3.453, P<0.01.The fish catch composed of Mystus gulio 79%, Osteochilus hasselti 10%, Hypostomus plecostomus 7%, and Macrognathus aculeatus 3%, with total weight ranged from 35 to 560 g. A clear difference was found in catching efficiency. Comparative fishing trials showed that Tamba collected specimens were 1.8 times higher than Ayunan (T=2.223, P<0.05. Catch per unit effort for Tamba ranged from 58.13 to 80.00, and for Ayunan ranged from 5.31 to 7.19. The gear modifications and various treatments (e.g. bait odor, light are necessary to be taken to increase their relative catching efficiency.

  8. Phylogeny of the Paracalanidae Giesbrecht, 1888 (Crustacea: Copepoda: Calanoida).

    Science.gov (United States)

    Cornils, Astrid; Blanco-Bercial, Leocadio

    2013-12-01

    The Paracalanidae are ecologically-important marine planktonic copepods that occur in the epipelagic zone in temperate and tropical waters. They are often the dominant taxon - in terms of biomass and abundance - in continental shelf regions. As primary consumers, they form a vital link in the pelagic food web between primary producers and higher trophic levels. Despite the ecological importance of the taxon, evolutionary and systematic relationships within the family remain largely unknown. A multigene phylogeny including 24 species, including representatives for all seven genera, was determined based on two nuclear genes, small-subunit (18S) ribosomal RNA and Histone 3 (H3) and one mitochondrial gene, cytochrome c oxidase subunit I (COI). The molecular phylogeny was well supported by Maximum likelihood and Bayesian inference analysis; all genera were found to be monophyletic, except for Paracalanus, which was separated into two distinct clades: the Paracalanus aculeatus group and Paracalanus parvus group. The molecular phylogeny also confirmed previous findings that Mecynocera and Calocalanus are genera of the family Paracalanidae. For comparison, a morphological phylogeny was created for 35 paracalanid species based on 54 morphological characters derived from published descriptions. The morphological phylogeny did not resolve all genera as monophyletic and bootstrap support was not strong. Molecular and morphological phylogenies were not congruent in the positioning of Bestiolina and the Paracalanus species groups, possibly due to the lack of sufficient phylogenetically-informative morphological characters. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Unravelling the nanostructure of strawberry fruit pectins by endo-polygalacturonase digestion and atomic force microscopy.

    Science.gov (United States)

    Paniagua, Candelas; Kirby, Andrew R; Gunning, A Patrick; Morris, Victor J; Matas, Antonio J; Quesada, Miguel A; Mercado, José A

    2017-06-01

    Pectins analysed by AFM are visualized as individual chains, branched or unbranched, and aggregates. To investigate the nature of these structures, sodium carbonate soluble pectins from strawberry fruits were digested with endo-polygalacturonase M2 from Aspergillus aculeatus and visualized by AFM. A gradual decrease in the length of chains was observed as result of the treatment, reaching a minimum LN value of 22nm. The branches were not visible after 2h of enzymatic incubation. The size of complexes also diminished significantly with the enzymatic digestion. A treatment to hydrolyse rhamnogalacturonan II borate diester bonds neither affected chains length or branching nor complex size but reduced the density of aggregates. These results suggest that chains are formed by a mixture of homogalacturonan and more complex molecules composed by a homogalacturonan unit linked to an endo-PG resistant unit. Homogalacturonan is a structural component of the complexes and rhamnogalacturonan II could be involved in their formation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. CYP1A inhibition in fish gill filaments: A novel assay applied on pharmaceuticals and other chemicals

    Energy Technology Data Exchange (ETDEWEB)

    Beijer, Kristina; Abrahamson, Alexandra; Brunstroem, Bjoern [Department of Environmental Toxicology, Uppsala University, Norbyvaegen 18A, SE-752 36 Uppsala (Sweden); Brandt, Ingvar, E-mail: ingvar.brandt@ebc.uu.se [Department of Environmental Toxicology, Uppsala University, Norbyvaegen 18A, SE-752 36 Uppsala (Sweden)

    2010-01-31

    The gill filament 7-ethoxyresorufin O-deethylase (EROD) assay was originally developed as a biomarker for cytochrome P4501A (CYP1A) induction by Ah-receptor agonists in water. In this study, the assay was adapted to measure inhibition of CYP1A activity in fish gill filaments ex vivo. The experiments were carried out using gill arch filaments from {beta}-naphthoflavone ({beta}NF)-exposed three-spined stickleback (Gasterosteus aculeatus). Candidate CYP1A inhibitors were added to the assay buffer. Nine selected pharmaceuticals and five known or suspected CYP1A-modulating chemicals were examined with regard to their ability to reduce EROD activity in gill filaments. Ellipticine, a well characterized CYP1A inhibitor, was the most effective inhibitor of the compounds tested. At a concentration in the assay buffer of 1 {mu}M the antifungal azoles ketoconazole, miconazole and bitertanol, and the plant flavonoid acacetin reduced gill EROD activity by more than 50%, implying IC50 values below 1 {mu}M. These compounds have previously been shown to inhibit EROD activity in liver microsomes from fish and mammals at similar concentrations. The proton pump inhibitor omeprazole reduced the gill EROD activity by 39% at 10 {mu}M. It is concluded that the modified gill filament EROD assay is useful to screen for waterborne pollutants that inhibit catalytic CYP1A activity in fish gills.

  11. The relationship between intraspecific assortative mating and reproductive isolation between divergent populations

    Institute of Scientific and Technical Information of China (English)

    Daniel I.BOLNICK; Mark KIRKPATRICK

    2012-01-01

    The term'assortative mating' has been applied to describe two very different phenomena:(1) the tendency for individuals to choose phenotypically similar mates from among conspecifics; or (2) the tendency to prefer conspecific over heterospecific mates (behavioral reproductive isolation).Both forms of assortative mating are widespread in nature,but the relationship between these behaviors remains unclear.Namely,it is plausible that a preference for phenotypically similar conspecifics incidentally reduces the probability of mating with phenotypically divergent heterospecifics.We present a model to calculate how the level of reproductive isolation depends on intraspecific assortative mating and the phenotypic divergence between species.For empirically reasonable levels of intraspecific assortment on a single trait axis,we show that strong reproductive isolation requires very substantial phenotypic divergence.We illustrate this point by applying our model to empirical data from threespine stickleback Gasterosteus aculeatus and Darwin's Finches (Geospiza spp).We conclude that typical levels of intraspecific assortment cannot generally be extrapolated to explain levels of interspecitie reproductive isolation.Instead,reproductive isolation between species likely arises from different mate choice behaviors,or multivariate assortative mating.

  12. Female sticklebacks use male coloration in mate choice and hence avoid parasitized males

    Science.gov (United States)

    Milinski, Manfred; Bakker, Theo C. M.

    1990-03-01

    AN important problem in evolutionary biology since the time of Darwin has been to understand why females preferentially mate with males handicapped by secondary sexual ornaments1-3. One hypothesis of sexual selection theory is that these ornaments reliably reveal the male's condition4-6, which can be affected for example by parasites4,7-13. Here we show that in the three-spined stickleback (Gasterosteus aculeatus) the intensity of male red breeding coloration positively correlates with physical condition. Gravid females base their active mate choice on the intensity of the male's red coloration. Choice experiments under green light prevent the use of red colour cues by females, and males that were previously preferred are now chosen no more than randomly, although the courtship behaviour of the males remains unchanged. Parasitieation causes a deterioration in the males' condition and a decrease in the intensity of their red coloration. Tests under both lighting conditions reveal that the females recognize the formerly parasitized males by the lower intensity of their breeding coloration. Female sticklebacks possibly select a male with a good capacity for paternal care14 but if there is additive genetic variation for parasite resistance, then they might also select for resistance genes, as proposed by Hamilton and Zuk4.

  13. Involvement of TBL/DUF231 proteins into cell wall biology.

    Science.gov (United States)

    Bischoff, Volker; Selbig, Joachim; Scheible, Wolf-Rüdiger

    2010-08-01

    Through map-based cloning we determined TRICHOME BIREFRINGENCE (TBR) to belong to a plant-specific, yet anonymous gene family with 46 members in Arabidopsis thaliana. These genes all encode the domain of unknown function 231 (DUF231). TBR and its homolog TRICHOME BIREFRINGENCE-LIKE3 (TBL3) are transcriptionally coordinated with CELLULOSE SYNTHASE (CESA) genes, and loss of TBR or TBL3 results in decreased levels of crystalline secondary wall cellulose in trichomes and stems, respectively. Loss of TBR or TBL3 further results in increased pectin methylesterase (PME) activity and reduced pectin esterification in etiolated Arabidopsis hypocotyls. Together, the results suggest that DUF231 proteins might function in the maintenance of pectin- and probably homogalacturonan esterification, and that this is a requirement for normal secondary wall cellulose synthesis, at least in some tissues and organs. Here we expand the discussion about the role of TBL/DUF231 proteins in cell wall biology based on sequence and structure analyses. Our analysis revealed structural similarities of TBR with a rhamnogalacturonan acetylesterase (RGAE) of Aspergillus aculeatus and the protein LUSTRIN A-LIKE (Oryza sativa). The implications of these findings in regard to TBL functions are discussed.

  14. Species composition and dietary relationships in a brackish shallow water fish assemblage in the Bothnian Sea, Sweden

    Science.gov (United States)

    Thorman, Staffan; Wiederholm, Anne-Marie

    1984-09-01

    A nearshore fish assemblage inhabiting a shallow bay in the southern Bothnian Sea, Sweden, with demanding environmental conditions (c. 5‰; >15°C during 4 months 1980 and 1 month 1981) was studied during a two-year period, in 1980 and 1981. Seasonal distribution patterns, dietary relationships, and growth rates were studied in Pungitius pungitius (L.), Pomatoschistus minutus (Pallas.), Gasterosteus aculeatus (L.), Phoxinus phoxinus (L.), Pomatoschistus microps (Krøyer) and Gobius niger L. The structure of the juvenile populations changed both over seasons and years but the adult populations remained constant. Lower water temperature, fewer individuals, lower and delayed fish growth, and lower interspecific food overlaps were found in 1981 compared to 1980. Few significant correlations were found in both years between the following community parameters: diversity, niche width, food overlap, and the proportion of each species in the fish assemblage. According to these results it is suggested that food competition and resource partitioning were of minor importance for the structuring of the fish community in the present area. Rather, the extreme salinity and the fluctuations in temperature regulated the fish populations. One may conclude that the populations of juveniles were more influenced by short-term changes in the environment than those of the adults.

  15. Environmental enrichment, sexual dimorphism, and brain size in sticklebacks.

    Science.gov (United States)

    Toli, Elisavet A; Noreikiene, Kristina; DeFaveri, Jacquelin; Merilä, Juha

    2017-03-01

    Evidence for phenotypic plasticity in brain size and the size of different brain parts is widespread, but experimental investigations into this effect remain scarce and are usually conducted using individuals from a single population. As the costs and benefits of plasticity may differ among populations, the extent of brain plasticity may also differ from one population to another. In a common garden experiment conducted with three-spined sticklebacks (Gasterosteus aculeatus) originating from four different populations, we investigated whether environmental enrichment (aquaria provided with structural complexity) caused an increase in the brain size or size of different brain parts compared to controls (bare aquaria). We found no evidence for a positive effect of environmental enrichment on brain size or size of different brain parts in either of the sexes in any of the populations. However, in all populations, males had larger brains than females, and the degree of sexual size dimorphism (SSD) in relative brain size ranged from 5.1 to 11.6% across the populations. Evidence was also found for genetically based differences in relative brain size among populations, as well as for plasticity in the size of different brain parts, as evidenced by consistent size differences among replicate blocks that differed in their temperature.

  16. Reverse Evolution of Armor Plates in the Threespine Stickleback

    Science.gov (United States)

    Kitano, J.; Bolnick, D.I.; Beauchamp, D.A.; Mazur, M.M.; Mori, S.; Nakano, T.; Peichel, C.L.

    2008-01-01

    Faced with sudden environmental changes, animals must either adapt to novel environments or go extinct. Thus, study of the mechanisms underlying rapid adaptation is crucial not??only for the understanding of natural evolutionary processes but also for the understanding of human-induced evolutionary change, which is an increasingly important problem [1-8]. In the present study, we demonstrate that the frequency of completely plated threespine stickleback fish (Gasterosteus aculeatus) has increased in an urban freshwater lake (Lake Washington, Seattle, Washington) within the last 40 years. This is a dramatic example of "reverse evolution," [9] because the general evolutionary trajectory is toward armor-plate reduction in freshwater sticklebacks [10]. On the basis of our genetic studies and simulations, we propose that the most likely cause of reverse evolution is increased selection for the completely plated morph, which we suggest could result from higher levels of trout predation after a sudden increase in water transparency during the early 1970s. Rapid evolution was facilitated by the existence of standing allelic variation in Ectodysplasin (Eda), the gene that underlies the major plate-morph locus [11]. The Lake Washington stickleback thus provides a novel example of reverse evolution, which is probably caused by a change in allele frequency at the major plate locus in response to a changing predation regime. ?? 2008 Elsevier Ltd. All rights reserved.

  17. Bioactive compounds, RP-HPLC analysis of phenolics, and antioxidant activity of some Portuguese shrub species extracts.

    Science.gov (United States)

    Luís, Angelo; Domingues, Fernanda; Duarte, Ana Paula

    2011-12-01

    In the ecosystem of Serra Da Estrela, some plant species have the potential to be used as raw material for extraction of bioactive products. The goal of this work was to determine the phenolic, flavonoid, tannin and alkaloid contents of the methanolic extracts of some shrubs (Echinospartum ibericum, Pterospartum tridentatum, Juniperus communis, Ruscus aculeatus, Rubus ulmifolius, Hakea sericea, Cytisus multiflorus, Crataegus monogyna, Erica arborea and Ipomoea acuminata), and then to correlate the phenolic compounds and flavonoids with the antioxidant activity of each extract. The Folin-Ciocalteu's method was used for the determination of total phenols, and tannins were then precipitated with polyvinylpolypyrrolidone (PVPP); a colorimetric method with aluminum chloride was used for the determination of flavonoids, and a Dragendorff's reagent method was used for total alkaloid estimation. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) and beta-carotene bleaching tests were used to assess the antioxidant activity of extracts. The identification of phenolic compounds present in extracts was performed using RP-HPLC. A positive linear correlation between antioxidant activity index and total phenolic content of methanolic extracts was observed. The RP-HPLC procedure showed that the most common compounds were ferulic and ellagic acids and quercetin. Most of the studied shrubs have significant antioxidant properties that are probably due to the existence of phenolic compounds in the extracts. It is noteworthy to emphasize that for Echinospartum ibericum, Hakea sericea and Ipomoea acuminata, to the best of our knowledge, no phytochemical studies have been undertaken nor their use in traditional medicine been described.

  18. A CRISPR-Cas9 System for Genetic Engineering of Filamentous Fungi.

    Science.gov (United States)

    Nødvig, Christina S; Nielsen, Jakob B; Kogle, Martin E; Mortensen, Uffe H

    2015-01-01

    The number of fully sequenced fungal genomes is rapidly increasing. Since genetic tools are poorly developed for most filamentous fungi, it is currently difficult to employ genetic engineering for understanding the biology of these fungi and to fully exploit them industrially. For that reason there is a demand for developing versatile methods that can be used to genetically manipulate non-model filamentous fungi. To facilitate this, we have developed a CRISPR-Cas9 based system adapted for use in filamentous fungi. The system is simple and versatile, as RNA guided mutagenesis can be achieved by transforming a target fungus with a single plasmid. The system currently contains four CRISPR-Cas9 vectors, which are equipped with commonly used fungal markers allowing for selection in a broad range of fungi. Moreover, we have developed a script that allows identification of protospacers that target gene homologs in multiple species to facilitate introduction of common mutations in different filamentous fungi. With these tools we have performed RNA-guided mutagenesis in six species of which one has not previously been genetically engineered. Moreover, for a wild-type Aspergillus aculeatus strain, we have used our CRISPR Cas9 system to generate a strain that contains an AACU_pyrG marker and demonstrated that the resulting strain can be used for iterative gene targeting.

  19. Population structure and effective/census population size ratio in threatened three-spined stickleback populations from an isolated river basin in northwest Spain.

    Science.gov (United States)

    Pérez-Figueroa, A; Fernández, C; Amaro, R; Hermida, M; San Miguel, E

    2015-08-01

    Variability at 20 microsatellite loci was examined to assess the population genetic structure, gene flow, and effective population size (N(e)) in three populations of three-spined stickleback (Gasterosteus aculeatus) from the upper basin of the Miño River in Galicia, NW Spain, where this species is threatened. The three populations showed similar levels of genetic diversity. There is a significant genetic differentiation between the three populations, but also significant gene flow. N(e) estimates based on linkage disequilibrium yielded values of 355 for the Miño River population and 241 and 311 for the Rato and Guisande Rivers, respectively, although we expect that these are overestimates. N(e) estimates based on temporal methods, considering gene flow or not, for the tributaries yielded values of 30-56 and 47-56 for the Rato and Guisande Rivers, respectively. Estimated census size (N(c)) for the Rato River was 880 individuals. This yielded a N(e)/N(c) estimate of 3-6 % for temporal estimation of N(e), which is within the empirical range observed in freshwater fishes. We suggest that the three populations analyzed have a sufficient level of genetic diversity with some genetic structure. Additionally, the absence of physical barriers suggests that conservation efforts and monitoring should focus in the whole basin as a unit.

  20. Salinity Preference in the Estuarine Teleost Fish Mummichog (Fundulus heteroclitus): Halocline Behavior.

    Science.gov (United States)

    Marshall, W S; Tait, J C; Mercer, E W

    2016-01-01

    Mummichogs prefer seawater (SW) but have wide ability to acclimate to extreme temperatures and salinities. In the field, minnow trapping revealed that mummichogs move progressively into low-salinity warmer water during early spring after ice melt and show significant aversion to colder temperatures and high salinity. First appearance in estuarine shallows occurred above 10°C, and catch increased to 21°C over 4 wk. Three-spine sticklebacks (Gasterosteus aculeatus) also preferred warmer low-salinity locations but preferred slowing streams, whereas mummichogs preferred tidal ponds. In the laboratory, artificial haloclines tested isothermal salinity preference, between 28‰ full-strength SW (below) and 10% SW (3.0‰; above). Mummichogs of both sexes acclimated to 5°C in SW strongly preferred SW. Freshwater (0% SW)-acclimated mummichogs at 21°C also preferred SW, but of sexually mature fish acclimated to 21°C SW, only the males preferred SW; the females showed no significant preference for SW, meaning they freely entered low salinity. SW preference was manifested by a stereotypic passive aversion to the dilute upper layer at the halocline. We conclude that the overall movement of mummichogs into summer breeding grounds of low salinity is driven by maturation of females and their preference for warmer water regardless of salinity.

  1. Consensus and experience trump leadership, suppressing individual personality during social foraging.

    Science.gov (United States)

    McDonald, Nicholas D; Rands, Sean A; Hill, Francesca; Elder, Charlotte; Ioannou, Christos C

    2016-09-01

    Whether individual behavior in social settings correlates with behavior when individuals are alone is a fundamental question in collective behavior. However, evidence for whether behavior correlates across asocial and social settings is mixed, and no study has linked observed trends with underlying mechanisms. Consistent differences between individuals in boldness, which describes willingness to accept reward over risk, are likely to be under strong selection pressure. By testing three-spined sticklebacks (Gasterosteus aculeatus) in a risky foraging task alone and repeatedly in shoals, we demonstrate that the expression of boldness in groups is context-specific. Whereas personality is repeatable in a low-risk behavior (leaving a refuge), the collectively made consensus decision to then cross the arena outweighs leadership by bolder individuals, explaining the suppression of personality in this context. However, despite this social coordination, bolder individuals were still more likely to feed. Habituation and satiation over repeated trials degrade the effect of personality on leaving the refuge and also whether crossing the arena is a collective decision. The suppression of personality in groups suggests that individual risk-taking tendency may rarely represent actual risk in social settings, with implications for the evolution and ecology of personality variation.

  2. Increased noise levels have different impacts on the anti-predator behaviour of two sympatric fish species.

    Directory of Open Access Journals (Sweden)

    Irene K Voellmy

    Full Text Available Animals must avoid predation to survive and reproduce, and there is increasing evidence that man-made (anthropogenic factors can influence predator-prey relationships. Anthropogenic noise has been shown to have a variety of effects on many species, but work investigating the impact on anti-predator behaviour is rare. In this laboratory study, we examined how additional noise (playback of field recordings of a ship passing through a harbour, compared with control conditions (playback of recordings from the same harbours without ship noise, affected responses to a visual predatory stimulus. We compared the anti-predator behaviour of two sympatric fish species, the three-spined stickleback (Gasterosteus aculeatus and the European minnow (Phoxinus phoxinus, which share similar feeding and predator ecologies, but differ in their body armour. Effects of additional-noise playbacks differed between species: sticklebacks responded significantly more quickly to the visual predatory stimulus during additional-noise playbacks than during control conditions, while minnows exhibited no significant change in their response latency. Our results suggest that elevated noise levels have the potential to affect anti-predator behaviour of different species in different ways. Future field-based experiments are needed to confirm whether this effect and the interspecific difference exist in relation to real-world noise sources, and to determine survival and population consequences.

  3. Resveratrol and the pharmacology of aging: a new vertebrate model to validate an old molecule.

    Science.gov (United States)

    Valenzano, Dario Riccardo; Cellerino, Alessandro

    2006-05-01

    The natural phytoalexin resveratrol, found in grapes and red wine, recently rose to public fame for its positive effects on longevity in yeasts, worms and flies. Resveratrol anti-cancer and anti-inflammatory in vitro action on mammalian cell cultures also suggest a possible positive effect on human health and life-expectancy. To study the effects of resveratrol on vertebrate aging is obviously a particularly relevant question. We have studied resveratrol effects in a very short-lived vertebrate: the annual fish Nothobranchius furzeri. Resveratrol treatment prolonged lifespan and delayed the onset of age-related dysfunctions in this fish. This result identifies resveratrol as the first molecule which consistently retards aging in organisms as diverse as yeast, worm, fly and fish, but it also reveals the potential of this short-lived fish as an animal model for pharmacological research. Moreover, being related to stickleback (Gasterosteus aculeatus) the "pufferfishes" Takifugu and Tetraodon, and even more closely related to medaka (Oryzias latipes), it can greatly beneficiate from the recent development of genomic resources for these fish models and in the future become a complete model system for the aging research community.

  4. Exogenous iodide ameliorates perchlorate-induced thyroid phenotypes in threespine stickleback.

    Science.gov (United States)

    Gardell, Alison M; von Hippel, Frank A; Adams, Elise M; Dillon, Danielle M; Petersen, Ann M; Postlethwait, John H; Cresko, William A; Buck, C Loren

    2017-03-01

    Perchlorate is a ubiquitous environmental contaminant that has widespread endocrine disrupting effects in vertebrates, including threespine stickleback (Gasterosteus aculeatus). The target of perchlorate is thyroid tissue where it induces changes in the organization, activation, and morphology of thyroid follicles and surrounding tissues. To test the hypothesis that some phenotypes of perchlorate toxicity are not mediated by thyroid hormone, we chronically exposed stickleback beginning at fertilization to perchlorate (10, 30, 100ppm) or control water with and without supplementation of either iodide or thyroxine (T4). Stickleback were sampled across a one-year timespan to identify potential differences in responses to treatment combinations before and after sexual maturation. We found that most thyroid histomorphological phenotypes induced by perchlorate (follicle proliferation, reduced follicle area (adults only), colloid depletion, thyrocyte hypertrophy (subadults only)) were significantly ameliorated by exogenous iodide supplementation. In contrast, treatment with exogenous T4 did not correct any of the thyroid-specific histopathologies induced by perchlorate. Whole-body thyroid hormone concentrations were not significantly affected by perchlorate exposure; however, supplementation with iodide and T4 significantly increased T4 concentrations. This study also revealed an increased erythrocyte area in the thyroid region of perchlorate-exposed adults, while lipid droplet number increased in perchlorate-exposed subadults. Increased erythrocyte area was ameliorated by both iodide and T4, while neither supplement was able to correct lipid droplet number. Our finding on lipid droplets indicates that exposure to perchlorate in early development may have obesogenic effects. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Fine structure and cellular responses at the host-parasite interface in a range of fish-helminth systems.

    Science.gov (United States)

    Dezfuli, B S; Bo, T; Lorenzoni, M; Shinn, A P; Giari, L

    2015-03-15

    A series of ultrastructural-based studies were conducted on the interface region in different fish-helminth systems: (a) an intestinal infection of the cestode Monobothrium wageneri in tench, Tinca tinca; (b) an extensive intestinal submucosa and mucosal infection in tench by metacercariae of an unidentified digenean trematode; (c) an intestinal infection in brown trout, Salmo trutta, by the acanthocephalan Dentitruncus truttae; (d) an extraintestinal infection by larvae of the acanthocephalan, Pomphorhynchus laevis in three-spined sticklebacks, Gasterosteus aculeatus; and (e) an infection in the livers of Eurasian minnow, Phoxinus phoxinus, by larvae of the nematode Raphidascaris acus. Endoparasitic helminths frequently cause inflammation of the digestive tract and associated organs, inducing the recruitment of various immune cells to the site of infection. In each of the fish-helminth systems that were studied, a massive hyperplastic granulocyte response involving mast cells (MCs) and neutrophils in close proximity to the helminths was documented. The current study presents data on the interface region in each fish-helminth system and documents the penetration of mast cells granules within the tegument of P. laevis larvae. No extracellular vesicles containing tegumental secretions from any of the four different taxa of endoparasitic helminths species at the host-parasite interface region were seen.

  6. Nursery use of shallow habitats by epibenthic fishes in Maine nearshore waters

    Science.gov (United States)

    Lazzari, M. A.; Sherman, S.; Kanwit, J. K.

    2003-01-01

    Species richness and abundance of epibenthic fishes were quantified with daytime beam trawl tows in shallow water habitats during April-November 2000 of three mid-coast Maine estuaries: Casco Bay, Muscongus Bay and the Weskeag River. Five shallow (fishes were collected. Species richness per tow was greater in Casco Bay followed by the Weskeag River and Muscongus Bay. Catch per unit effort (CPUE) of fishes was greater in Casco Bay than in the Weskeag River or Muscongus Bay. Species richness and faunal abundances were positively associated with vegetation, particularly Zostera, at all sampling locations. CPUEs of fishes were higher in Zostera primarily due to the abundance of Gasterosteus aculeatus, Apeltes quadracus, Pungitius pungitius, Myoxocephalus aenaeus, and Cylcopterus lumpus. The fish community of mid-coast estuaries was dominated by young-of-the-year (YOY) and juvenile fishes and all of the habitat types function as nursery areas. Twelve species (38%) of commercial and recreational importance were collected in the three estuaries, but the percentage was higher in Casco Bay (44%) and the Weskeag River (46%). These species included Anguilla rostrata, Clupea harengus, Gadus morhua, Microgadus tomcod, Pollachius virens, Urophycis chuss, Urophycis regia, Urophycis tenuis, Osmerus mordax, Macrozoarces americanus, Tautogolabrus adspersus, and Pleuronectes americanus. Four species, G. morhua, M. tomcod, P. virens, and U. tenuis were more common in spring than summer or autumn. P. americanus was most abundant in summer followed by spring and autumn. This study documents the importance of shallow estuarine areas in Maine as nurseries for these species.

  7. Social Regulation of Gene Expression in Threespine Sticklebacks.

    Directory of Open Access Journals (Sweden)

    Anna K Greenwood

    Full Text Available Identifying genes that are differentially expressed in response to social interactions is informative for understanding the molecular basis of social behavior. To address this question, we described changes in gene expression as a result of differences in the extent of social interactions. We housed threespine stickleback (Gasterosteus aculeatus females in either group conditions or individually for one week, then measured levels of gene expression in three brain regions using RNA-sequencing. We found that numerous genes in the hindbrain/cerebellum had altered expression in response to group or individual housing. However, relatively few genes were differentially expressed in either the diencephalon or telencephalon. The list of genes upregulated in fish from social groups included many genes related to neural development and cell adhesion as well as genes with functions in sensory signaling, stress, and social and reproductive behavior. The list of genes expressed at higher levels in individually-housed fish included several genes previously identified as regulated by social interactions in other animals. The identified genes are interesting targets for future research on the molecular mechanisms of normal social interactions.

  8. Predator-induced reduction of freshwater carbon dioxide emissions

    Science.gov (United States)

    Atwood, Trisha B.; Hammill, Edd; Greig, Hamish S.; Kratina, Pavel; Shurin, Jonathan B.; Srivastava, Diane S.; Richardson, John S.

    2013-03-01

    Predators can influence the exchange of carbon dioxide between ecosystems and the atmosphere by altering ecosystem processes such as decomposition and primary production, according to food web theory. Empirical knowledge of such an effect in freshwater systems is limited, but it has been suggested that predators in odd-numbered food chains suppress freshwater carbon dioxide emissions, and predators in even-numbered food chains enhance emissions. Here, we report experiments in three-tier food chains in experimental ponds, streams and bromeliads in Canada and Costa Rica in the presence or absence of fish (Gasterosteus aculeatus) and invertebrate (Hesperoperla pacifica and Mecistogaster modesta) predators. We monitored carbon dioxide fluxes along with prey and primary producer biomass. We found substantially reduced carbon dioxide emissions in the presence of predators in all systems, despite differences in predator type, hydrology, climatic region, ecological zone and level of in situ primary production. We also observed lower amounts of prey biomass and higher amounts of algal and detrital biomass in the presence of predators. We conclude that predators have the potential to markedly influence carbon dioxide dynamics in freshwater systems.

  9. Two developmentally temporal quantitative trait loci underlie convergent evolution of increased branchial bone length in sticklebacks.

    Science.gov (United States)

    Erickson, Priscilla A; Glazer, Andrew M; Cleves, Phillip A; Smith, Alyson S; Miller, Craig T

    2014-08-07

    In convergent evolution, similar phenotypes evolve repeatedly in independent populations, often reflecting adaptation to similar environments. Understanding whether convergent evolution proceeds via similar or different genetic and developmental mechanisms offers insight towards the repeatability and predictability of evolution. Oceanic populations of threespine stickleback fish, Gasterosteus aculeatus, have repeatedly colonized countless freshwater lakes and streams, where new diets lead to morphological adaptations related to feeding. Here, we show that heritable increases in branchial bone length have convergently evolved in two independently derived freshwater stickleback populations. In both populations, an increased bone growth rate in juveniles underlies the convergent adult phenotype, and one population also has a longer cartilage template. Using F2 crosses from these two freshwater populations, we show that two quantitative trait loci (QTL) control branchial bone length at distinct points in development. In both populations, a QTL on chromosome 21 controls bone length throughout juvenile development, and a QTL on chromosome 4 controls bone length only in adults. In addition to these similar developmental profiles, these QTL show similar chromosomal locations in both populations. Our results suggest that sticklebacks have convergently evolved longer branchial bones using similar genetic and developmental programmes in two independently derived populations. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  10. Quantitative genetic analysis of brain size variation in sticklebacks: support for the mosaic model of brain evolution.

    Science.gov (United States)

    Noreikiene, Kristina; Herczeg, Gábor; Gonda, Abigél; Balázs, Gergely; Husby, Arild; Merilä, Juha

    2015-07-07

    The mosaic model of brain evolution postulates that different brain regions are relatively free to evolve independently from each other. Such independent evolution is possible only if genetic correlations among the different brain regions are less than unity. We estimated heritabilities, evolvabilities and genetic correlations of relative size of the brain, and its different regions in the three-spined stickleback (Gasterosteus aculeatus). We found that heritabilities were low (average h(2) = 0.24), suggesting a large plastic component to brain architecture. However, evolvabilities of different brain parts were moderate, suggesting the presence of additive genetic variance to sustain a response to selection in the long term. Genetic correlations among different brain regions were low (average rG = 0.40) and significantly less than unity. These results, along with those from analyses of phenotypic and genetic integration, indicate a high degree of independence between different brain regions, suggesting that responses to selection are unlikely to be severely constrained by genetic and phenotypic correlations. Hence, the results give strong support for the mosaic model of brain evolution. However, the genetic correlation between brain and body size was high (rG = 0.89), suggesting a constraint for independent evolution of brain and body size in sticklebacks.

  11. Axial variation in the three-spine stickleback: genetic and environmental factors.

    Science.gov (United States)

    Ahn, D G; Gibson, G

    1999-01-01

    Subtle differences in the pattern of arrangement of types of vertebrae and associated median skeletal structures between a benthic and limnetic species pair of three-spine stickleback from Paxton Lake, British Columbia, are typical of those found throughout the range of the Gasterosteus aculeatus species complex. We established laboratory colonies from just three individuals of each species, and studied the effect of three generations of inbreeding on axial morphology. There was sufficient divergence in the location of individual elements between families to regenerate close to the entire range of axial diversity seen in threespine sticklebacks worldwide. Analysis of the patterns of variance and covariance between the axial locations of elements provides evidence for the action of both meristic and homeotic processes in the generation of morphological divergence within each species. Hybrid sticklebacks produced by the cross of limnetic and benthic parents tend to have intermediate morphologies, with dominance of either parental type evident for some elements. Effects of temperature and salinity were found to be small in direct comparison with between-family effects, and varied according to genetic background. These results demonstrate that considerable genetic variation for axial morphology is maintained in natural populations of three-spine stickleback, and that differences between populations may be brought about rapidly by changes in frequency of alleles that have coordinated effects along the body axis.

  12. Diplostomum von Nordmann, 1832 (Digenea: Diplostomidae) in the sub-Arctic: descriptions of the larval stages of six species discovered recently in Iceland.

    Science.gov (United States)

    Faltýnková, Anna; Georgieva, Simona; Kostadinova, Aneta; Blasco-Costa, Isabel; Scholz, Tomáš; Skírnisson, Karl

    2014-11-01

    Frequent infections with Diplostomum spp. (Digenea: Diplostomidae) were found in the freshwater snail Radix peregra (Müller) and three fish species, the salmonids Salmo trutta fario L., Salvelinus alpinus (L.) and the gasterosteid Gasterosteus aculeatus L., collected in four lakes in south-western Iceland in 2012. Detailed analysis of the isolates integrating molecular, morphological and ecological data revealed that these belong to Diplostomum spathaceum (Rudolphi, 1819) and five putative new species (three infecting both snails and fish). This paper provides detailed descriptions of the metacercariae of the six species-level lineages of Diplostomum spp. and of the cercariae of three of the lineages discovered in Iceland with comments on the application of ITS1 rDNA for species distinction within Diplostomum von Nordmann, 1832 in the light of the novel data. We strongly suggest the use of molecular evidence based on cox1 gene sequences (in addition to ITS1-5.8S-ITS2 sequences) in association with detailed assessment of the morphology of the larval stages in future studies of Diplostomum spp. in fish and snails.

  13. Enzymes of Trichoderma and other origin in biopreparation of cotton

    Institute of Scientific and Technical Information of China (English)

    Anita Losonczi; George Szakacs; Emilia Csiszar; Outi Kareela

    2004-01-01

    @@ Preparation and bleaching are among the most energy and chemical intensive steps of the traditional cotton finishing. About 75 % of the organic pollutants arising from textile finishing are derived from the preparation of cotton goods. Biopreparation may be a valuable and environmentally friendly alternative to harsh alkaline chemicals for preparing of cotton. Different enzymes i. e. cellulases,pectinases, lipases and proteases have been tested for biopreparation. Many papers have been published how enzymes effect on the properties of cotton fabrics in respect to their effectiveness to replace alkaline scouring and how enzymes modify the various cell wall components of cotton fibers. However,very few data have been reported on bleachability and dyeing behavior of the bioscoured fabrics. In this work an acidic cellulase (Celluclast 1.5 L, Trichoderma reesei origin), an acidic pectinasehemicellulase (Viscozyme 120 L , Aspergillus aculeatus ) and a cellulase-free xylanase (Pulpzyme HC,Bacillus sp. ) enzymes were used for bioscouring of greige cotton fabric. Selected properties of the pretreated samples, which are important for effective dyeing, are characterized in detail. Effect of hydrogen peroxide bleaching, applied subsequent to the biopretreatment on the bleachability and dyeing properties of the samples is also elucidated. A reactive dye was used at four different concentrations to compare the dyeing behavior of biopretreated as well as biopretreated and subsequently bleached cotton fabrics with that of the alkaline scoured as well as alkaline scoured and bleached fabrics, respectively. Color evenness and uniformity, and wash fastness properties of the dyed samples are also determined[1].

  14. Characterization of the Zoarces viviparus liver transcriptome using massively parallel pyrosequencing

    Directory of Open Access Journals (Sweden)

    Asker Noomi

    2009-07-01

    Full Text Available Abstract Background The teleost Zoarces viviparus (eelpout lives along the coasts of Northern Europe and has long been an established model organism for marine ecology and environmental monitoring. The scarce information about this species genome has however restrained the use of efficient molecular-level assays, such as gene expression microarrays. Results In the present study we present the first comprehensive characterization of the Zoarces viviparus liver transcriptome. From 400,000 reads generated by massively parallel pyrosequencing, more than 50,000 pieces of putative transcripts were assembled, annotated and functionally classified. The data was estimated to cover roughly 40% of the total transcriptome and homologues for about half of the genes of Gasterosteus aculeatus (stickleback were identified. The sequence data was consequently used to design an oligonucleotide microarray for large-scale gene expression analysis. Conclusion Our results show that one run using a Genome Sequencer FLX from 454 Life Science/Roche generates enough genomic information for adequate de novo assembly of a large number of genes in a higher vertebrate. The generated sequence data, including the validated microarray probes, are publicly available to promote genome-wide research in Zoarces viviparus.

  15. Traditional phytotherapy in Central Italy (Marche, Abruzzo, and Latium).

    Science.gov (United States)

    Guarrera, Paolo Maria

    2005-01-01

    In this study, the more significant results of extensive ethnopharmacobotanical research carried out by the author in the years 1977-2000 in 175 localities of three regions of Central Italy (Marche, Abruzzo, and Latium) have been reported and compared. The usages of 80 species belonging to 36 families are described, of which 71 were used in human therapy and 29 in veterinary medicine. Uses are suited with the number of localities in which they have been mentioned. Among the wild plant mainly still used, Malva sylvestris, Urtica dioica, and Sambucus nigra are particularly highly considered, while major uses of plants concern these plants in addition to Allium sativum, Rubus ulmifolius, Parietaria diffusa, Cynodon dactylon, and Ficus carica. Unusual phytotherapic uses concern Brassica oleracea, Taraxacum officinale (warts), Ruscus aculeatus, S. nigra (chilblains), Allium cepa (chilblains; to remove thorns and splinters), Juglans regia, R. ulmifolius (burns), and Euphorbia paralias (bites of weevers). Among new uses with only one quotation, we remember Cirsium arvense (intestinal disturbances), Centaurea bracteata (cough), Lupinus albus (calluses), Melittis melissophyllum (eye inflammations, antispasmodic), and Artemisia absinthium (tendon inflammations), while among plants employed in various regions with interesting less-known properties, there are C. arvense (emergency haemostatic), P. diffusa (insect bites), and Scrophularia canina (antiseptic and cicatrizing agent for wounds in bovines and sheep).

  16. Ephemeral stream reaches preserve the evolutionary and distributional history of threespine stickleback in the Santa Clara and Ventura River watersheds of southern California

    Science.gov (United States)

    Richmond, Jonathan Q.; Jacobs, David K.; Backlin, Adam R.; Swift, Camm C.; Dellith, Chris; Fisher, Robert N.

    2015-01-01

    Much remains to be understood about the evolutionary history and contemporary landscape genetics of unarmored threespine stickleback in southern California, where populations collectively referred to as Gasterosteus aculeatus williamsoni have severely declined over the past 70+ years and are now endangered. We used mitochondrial sequence and microsatellite data to assess the population genetics and phylogeography of unarmored populations sampled immediately downstream from the type locality of G. a. williamsoni in the upper Santa Clara River, and assessed their distinctiveness with respect to low-armor populations in the downstream sections of the river and the adjacent Ventura River. We also characterized the geographic limits of different plate morphs and evaluated the congruence of those boundaries with barriers to dispersal in both river systems and to neutral genetic variation. We show substantial population structuring within the upper reach of the Santa Clara River, but little partitioning between the lower Santa Clara and Ventura Rivers—we attribute these patterns to different ancestry between spatially subdivided populations within the same drainage, a predominance of downstream gene flow, and ability for coastal dispersal between the Santa Clara and Ventura Rivers. We also show that alleles from introduced low-plate stock have infiltrated a native population in at least one upper Santa Clara River tributary, causing this formerly unarmored population to become gradually low-plated over a 30 + year time period. Measures of genetic diversity, census surveys, and severe habitat disturbance all indicate that unarmored stickleback near the type locality are currently at high risk of extinction.

  17. Assessment and assortment: how fishes use local and global cues to choose which school to go to.

    Science.gov (United States)

    Ward, Ashley J W; Hart, Paul J B; Krause, Jens

    2004-08-01

    Animals that live in groups are known preferentially to associate with phenotypically similar individuals. Despite this, groups of mixed phenotypic composition are the norm rather than the exception in several systems in the wild and this, combined with the large sizes of some animal groups, makes accurate global assessment by a choosing individual more difficult. In this study, we investigated the role of local and global information in mediating shoal-choice decisions in three-spined sticklebacks (Gasterosteus aculeatus) by manipulating the positions and phenotypes of stimulus fish in relation to a focal fish. Focal fish were able to assess globally mixed shoals composed of individuals of different body-length classes, preferring to associate with shoals where the majority phenotype matched their own. When local cues were manipulated this preference disappeared, although overall shoal composition remaining constant. Finally, if both stimulus shoals had the same overall composition but differed in their local cues, then the focus fish chose according to which local fish was of matching body length. These findings indicate that both local and global information play an important role in mediating assessment and shoal choice in fishes.

  18. Diet of yellow-billed loons (Gavia adamsii) in Arctic lakes during the nesting season inferred from fatty acid analysis

    Science.gov (United States)

    Haynes, T B; Schmutz, Joel A.; Bromaghin, Jeffrey; Iverson, S J; Padula, V. M.; Rosenberger, A E

    2015-01-01

    Understanding the dietary habits of yellow-billed loons (Gavia adamsii) can give important insights into their ecology, however, studying the diet of loons is difficult when direct observation or specimen collection is impractical. We investigate the diet of yellow-billed loons nesting on the Arctic Coastal Plain of Alaska using quantitative fatty acid signature analysis. Tissue analysis from 26 yellow-billed loons and eleven prey groups (nine fish species and two invertebrate groups) from Arctic lakes suggests that yellow-billed loons are eating high proportions of Alaska blackfish (Dallia pectoralis), broad whitefish (Coregonus nasus) and three-spined stickleback (Gasterosteus aculeatus) during late spring and early summer. The prominence of blackfish in diets highlights the widespread availability of blackfish during the early stages of loon nesting, soon after spring thaw. The high proportions of broad whitefish and three-spined stickleback may reflect a residual signal from the coastal staging period prior to establishing nesting territories on lakes, when loons are more likely to encounter these species. Our analyses were sensitive to the choice of calibration coefficient based on data from three different species, indicating the need for development of loon-specific coefficients for future study and confirmation of our results. Regardless, fish that are coastally distributed and that successfully overwinter in lakes are likely key food items for yellow-billed loons early in the nesting season.

  19. Comparative population genetic analysis of bocaccio rockfish Sebastes paucispinis using anonymous and gene-associated simple sequence repeat loci.

    Science.gov (United States)

    Buonaccorsi, Vincent P; Kimbrell, Carol A; Lynn, Eric A; Hyde, John R

    2012-01-01

    Comparative population genetic analyses of traditional and emergent molecular markers aid in determining appropriate use of new technologies. The bocaccio rockfish Sebastes paucispinis is a high gene-flow marine species off the west coast of North America that experienced strong population decline over the past 3 decades. We used 18 anonymous and 13 gene-associated simple sequence repeat (SSR) loci (expressed sequence tag [EST]-SSRs) to characterize range-wide population structure with temporal replicates. No F(ST)-outliers were detected using the LOSITAN program, suggesting that neither balancing nor divergent selection affected the loci surveyed. Consistent hierarchical structuring of populations by geography or year class was not detected regardless of marker class. The EST-SSRs were less variable than the anonymous SSRs, but no correlation between F(ST) and variation or marker class was observed. General linear model analysis showed that low EST-SSR variation was attributable to low mean repeat number. Comparative genomic analysis with Gasterosteus aculeatus, Takifugu rubripes, and Oryzias latipes showed consistently lower repeat number in EST-SSRs than SSR loci that were not in ESTs. Purifying selection likely imposed functional constraints on EST-SSRs resulting in low repeat numbers that affected diversity estimates but did not affect the observed pattern of population structure.

  20. Consensus and experience trump leadership, suppressing individual personality during social foraging

    Science.gov (United States)

    McDonald, Nicholas D.; Rands, Sean A.; Hill, Francesca; Elder, Charlotte; Ioannou, Christos C.

    2016-01-01

    Whether individual behavior in social settings correlates with behavior when individuals are alone is a fundamental question in collective behavior. However, evidence for whether behavior correlates across asocial and social settings is mixed, and no study has linked observed trends with underlying mechanisms. Consistent differences between individuals in boldness, which describes willingness to accept reward over risk, are likely to be under strong selection pressure. By testing three-spined sticklebacks (Gasterosteus aculeatus) in a risky foraging task alone and repeatedly in shoals, we demonstrate that the expression of boldness in groups is context-specific. Whereas personality is repeatable in a low-risk behavior (leaving a refuge), the collectively made consensus decision to then cross the arena outweighs leadership by bolder individuals, explaining the suppression of personality in this context. However, despite this social coordination, bolder individuals were still more likely to feed. Habituation and satiation over repeated trials degrade the effect of personality on leaving the refuge and also whether crossing the arena is a collective decision. The suppression of personality in groups suggests that individual risk-taking tendency may rarely represent actual risk in social settings, with implications for the evolution and ecology of personality variation. PMID:27652342

  1. Exploring a Nonmodel Teleost Genome Through RAD Sequencing-Linkage Mapping in Common Pandora, Pagellus erythrinus and Comparative Genomic Analysis.

    Science.gov (United States)

    Manousaki, Tereza; Tsakogiannis, Alexandros; Taggart, John B; Palaiokostas, Christos; Tsaparis, Dimitris; Lagnel, Jacques; Chatziplis, Dimitrios; Magoulas, Antonios; Papandroulakis, Nikos; Mylonas, Constantinos C; Tsigenopoulos, Costas S

    2015-12-29

    Common pandora (Pagellus erythrinus) is a benthopelagic marine fish belonging to the teleost family Sparidae, and a newly recruited species in Mediterranean aquaculture. The paucity of genetic information relating to sparids, despite their growing economic value for aquaculture, provides the impetus for exploring the genomics of this fish group. Genomic tool development, such as genetic linkage maps provision, lays the groundwork for linking genotype to phenotype, allowing fine-mapping of loci responsible for beneficial traits. In this study, we applied ddRAD methodology to identify polymorphic markers in a full-sib family of common pandora. Employing the Illumina MiSeq platform, we sampled and sequenced a size-selected genomic fraction of 99 individuals, which led to the identification of 920 polymorphic loci. Downstream mapping analysis resulted in the construction of 24 robust linkage groups, corresponding to the karyotype of the species. The common pandora linkage map showed varying degrees of conserved synteny with four other teleost genomes, namely the European seabass (Dicentrarchus labrax), Nile tilapia (Oreochromis niloticus), stickleback (Gasterosteus aculeatus), and medaka (Oryzias latipes), suggesting a conserved genomic evolution in Sparidae. Our work exploits the possibilities of genotyping by sequencing to gain novel insights into genome structure and evolution. Such information will boost the study of cultured species and will set the foundation for a deeper understanding of the complex evolutionary history of teleosts.

  2. Exploring a Nonmodel Teleost Genome Through RAD Sequencing—Linkage Mapping in Common Pandora, Pagellus erythrinus and Comparative Genomic Analysis

    Directory of Open Access Journals (Sweden)

    Tereza Manousaki

    2016-03-01

    Full Text Available Common pandora (Pagellus erythrinus is a benthopelagic marine fish belonging to the teleost family Sparidae, and a newly recruited species in Mediterranean aquaculture. The paucity of genetic information relating to sparids, despite their growing economic value for aquaculture, provides the impetus for exploring the genomics of this fish group. Genomic tool development, such as genetic linkage maps provision, lays the groundwork for linking genotype to phenotype, allowing fine-mapping of loci responsible for beneficial traits. In this study, we applied ddRAD methodology to identify polymorphic markers in a full-sib family of common pandora. Employing the Illumina MiSeq platform, we sampled and sequenced a size-selected genomic fraction of 99 individuals, which led to the identification of 920 polymorphic loci. Downstream mapping analysis resulted in the construction of 24 robust linkage groups, corresponding to the karyotype of the species. The common pandora linkage map showed varying degrees of conserved synteny with four other teleost genomes, namely the European seabass (Dicentrarchus labrax, Nile tilapia (Oreochromis niloticus, stickleback (Gasterosteus aculeatus, and medaka (Oryzias latipes, suggesting a conserved genomic evolution in Sparidae. Our work exploits the possibilities of genotyping by sequencing to gain novel insights into genome structure and evolution. Such information will boost the study of cultured species and will set the foundation for a deeper understanding of the complex evolutionary history of teleosts.

  3. Exploring a Nonmodel Teleost Genome Through RAD Sequencing—Linkage Mapping in Common Pandora, Pagellus erythrinus and Comparative Genomic Analysis

    Science.gov (United States)

    Manousaki, Tereza; Tsakogiannis, Alexandros; Taggart, John B.; Palaiokostas, Christos; Tsaparis, Dimitris; Lagnel, Jacques; Chatziplis, Dimitrios; Magoulas, Antonios; Papandroulakis, Nikos; Mylonas, Constantinos C.; Tsigenopoulos, Costas S.

    2015-01-01

    Common pandora (Pagellus erythrinus) is a benthopelagic marine fish belonging to the teleost family Sparidae, and a newly recruited species in Mediterranean aquaculture. The paucity of genetic information relating to sparids, despite their growing economic value for aquaculture, provides the impetus for exploring the genomics of this fish group. Genomic tool development, such as genetic linkage maps provision, lays the groundwork for linking genotype to phenotype, allowing fine-mapping of loci responsible for beneficial traits. In this study, we applied ddRAD methodology to identify polymorphic markers in a full-sib family of common pandora. Employing the Illumina MiSeq platform, we sampled and sequenced a size-selected genomic fraction of 99 individuals, which led to the identification of 920 polymorphic loci. Downstream mapping analysis resulted in the construction of 24 robust linkage groups, corresponding to the karyotype of the species. The common pandora linkage map showed varying degrees of conserved synteny with four other teleost genomes, namely the European seabass (Dicentrarchus labrax), Nile tilapia (Oreochromis niloticus), stickleback (Gasterosteus aculeatus), and medaka (Oryzias latipes), suggesting a conserved genomic evolution in Sparidae. Our work exploits the possibilities of genotyping by sequencing to gain novel insights into genome structure and evolution. Such information will boost the study of cultured species and will set the foundation for a deeper understanding of the complex evolutionary history of teleosts. PMID:26715088

  4. Conspicuous carotenoid-based pelvic spine ornament in three-spined stickleback populations—occurrence and inheritance

    Directory of Open Access Journals (Sweden)

    CR Amundsen

    2015-04-01

    Full Text Available Reports on reddish carotenoid-based ornaments in female three-spined sticklebacks (Gasterosteus aculeatus are few, despite the large interest in the species’ behaviour, ornamentation, morphology and evolution. We sampled sticklebacks from 17 sites in north-western Europe in this first extensive study on the occurrence of carotenoid-based female pelvic spines and throat ornaments. The field results showed that females, and males, with reddish spines were found in all 17 populations. Specimens of both sexes with conspicuous red spines were found in several of the sites. The pelvic spines of males were more intensely red compared to the females’ spines, and large specimens were more red than small ones. Fish infected with the tapeworm (Schistocephalus solidus had drabber spines than uninfected fish. Both sexes had red spines both during and after the spawning period, but the intensity of the red colour was more exaggerated during the spawning period. As opposed to pelvic spines, no sign of red colour at the throat was observed in any female from any of the 17 populations. A rearing experiment was carried out to estimate a potential genetic component of the pelvic spine ornament by artificial crossing and rearing of 15 family groups during a 12 months period. The results indicated that the genetic component of the red colour at the spines was low or close to zero. Although reddish pelvic spines seem common in populations of stickleback, the potential adaptive function of the reddish pelvic spines remains largely unexplained.

  5. Stickleback Population

    Directory of Open Access Journals (Sweden)

    Ulrika Candolin

    2012-01-01

    Full Text Available Human-induced eutrophication has increased offspring production in a population of threespine stickleback Gasterosteus aculeatus in the Baltic Sea. Here, we experimentally investigated the effects of an increased density of juveniles on behaviours that influence survival and dispersal, and, hence, population growth—habitat choice, risk taking, and foraging rate. Juveniles were allowed to choose between two habitats that differed in structural complexity, in the absence and presence of predators and conspecific juveniles. In the absence of predators or conspecifics, juveniles preferred the more complex habitat. The preference was further enhanced in the presence of a natural predator, a perch Perca fluviatilis (behind a transparent Plexiglas wall. However, an increased density of conspecifics relaxed the predator-enhanced preference for the complex habitat and increased the use of the open, more predator-exposed habitat. Foraging rate was reduced under increased perceived predation risk. These results suggest that density-dependent behaviours can cause individuals to choose suboptimal habitats where predation risk is high and foraging rate low. This could contribute to the regulation of population growth in eutrophicated areas where offspring production is high.

  6. Revision of the genus Phyrella (Holothuroidea: Dendrochirotida) with the description of a new species from Guam.

    Science.gov (United States)

    Michonneau, François; Paulay, Gustav

    2014-01-31

    Recently collected material from Australia, Japan and Guam allowed us to revise Phyrella and describe Phyrella mookiei sp. nov. We redefine the genus based on combined morphological and molecular analyses. Phyrella unlike most dendrochirotids eviscerate posteriorly. The number of tentacles is variable (14-20), as is the degree of fragmentation of the calcareous ring, calling into question the separation of Phyllophorinae and Semperiellinae, and suggest that Semperiella and Thyonidiella are synonymous with Phyrella. We recognize five species in Phyrella (Phyllophorus trapezus Clark, 1932, Phyllophorus fragilis Mitsukuri & Ohshima, 1912 (synonymized with Thyonidiella oceana Heding & Panning, 1954), Phyllophorus thyonoides Clark, 1938, Semperiella drozdovi Levin & Stepanov, 1999, and Phyrella mookiei), assign three others provisionally (Lipotrapeza ambigua Cherbonnier, 1988 (synonymized with Phyllophorus contractura Cherbonnier, 1988 and Thyonidiella cherbonnieri Rowe & Richmond, 2004), Phyllophorus bedoti Koehler, 1895, and Orcula tenera Ludwig, 1875), considering the last two species inquirenda. Phyrella aculeatus (Ludwig, 1894), is transferred to Euthyonidiella. Orcula (Phyllophorus?) dubia Bedford, 1899, Thyonidiella exigua Cherbonnier, 1988 and Thyonidiella kungi O'Loughlin, 2012 are provisionally transferred to Phyllophorus sensu lato, the first is considered species inquirenda. Molecular phylogenetic analysis recovers a well-supported Phyrella, but suggests that some genera and subfamilies of Phyllophoridae are not monophyletic.

  7. Direct ethanol production from cellulosic materials at high temperature using the thermotolerant yeast Kluyveromyces marxianus displaying cellulolytic enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Yanase, Shuhei; Yamada, Ryosuke; Ogino, Chiaki; Kondo, Akihiko [Kobe Univ. (Japan). Dept. of Chemical Science and Engineering; Hasunuma, Tomohisa; Tanaka, Tsutomu; Fukuda, Hideki [Kobe Univ. (Japan). Organization of Advanced Science and Technology

    2010-09-15

    To exploit cellulosic materials for fuel ethanol production, a microorganism capable of high temperature and simultaneous saccharification-fermentation has been required. However, a major drawback is the optimum temperature for the saccharification and fermentation. Most ethanol-fermenting microbes have an optimum temperature for ethanol fermentation ranging between 28 C and 37 C, while the activity of cellulolytic enzymes is highest at around 50 C and significantly decreases with a decrease in temperature. Therefore, in the present study, a thermotolerant yeast, Kluyveromyces marxianus, which has high growth and fermentation at elevated temperatures, was used as a producer of ethanol from cellulose. The strain was genetically engineered to display Trichoderma reesei endoglucanase and Aspergillus aculeatus {beta}-glucosidase on the cell surface, which successfully converts a cellulosic {beta}-glucan to ethanol directly at 48 C with a yield of 4.24 g/l from 10 g/l within 12 h. The yield (in grams of ethanol produced per gram of {beta}-glucan consumed) was 0.47 g/g, which corresponds to 92.2% of the theoretical yield. This indicates that high-temperature cellulose fermentation to ethanol can be efficiently accomplished using a recombinant K. marxianus strain displaying thermostable cellulolytic enzymes on the cell surface. (orig.)

  8. Ecological and evolutionary effects of stickleback on community structure.

    Directory of Open Access Journals (Sweden)

    Simone Des Roches

    Full Text Available Species' ecology and evolution can have strong effects on communities. Both may change concurrently when species colonize a new ecosystem. We know little, however, about the combined effects of ecological and evolutionary change on community structure. We simultaneously examined the effects of top-predator ecology and evolution on freshwater community parameters using recently evolved generalist and specialist ecotypes of three-spine stickleback (Gasterosteus aculeatus. We used a mesocosm experiment to directly examine the effects of ecological (fish presence and density and evolutionary (phenotypic diversity and specialization factors on community structure at lower trophic levels. We evaluated zooplankton biomass and composition, periphyton and phytoplankton chlorophyll-a concentration, and net primary production among treatments containing different densities and diversities of stickleback. Our results showed that both ecological and evolutionary differences in the top-predator affect different aspects of community structure and composition. Community structure, specifically the abundance of organisms at each trophic level, was affected by stickleback presence and density, whereas composition of zooplankton was influenced by stickleback diversity and specialization. Primary productivity, in terms of chlorophyll-a concentration and net primary production was affected by ecological but not evolutionary factors. Our results stress the importance of concurrently evaluating both changes in density and phenotypic diversity on the structure and composition of communities.

  9. Strong and parallel salinity-induced phenotypic plasticity in one generation of threespine stickleback.

    Science.gov (United States)

    Mazzarella, A B; Voje, K L; Hansson, T H; Taugbøl, A; Fischer, B

    2015-03-01

    Phenotypic plasticity is a major factor contributing to variation of organisms in nature, yet its evolutionary significance is insufficiently understood. One example system where plasticity might have played an important role in an adaptive radiation is the threespine stickleback (Gasterosteus aculeatus), a fish that has diversified after invading freshwater lakes repeatedly from the marine habitat. The parallel phenotypic changes that occurred in this radiation were extremely rapid. This study evaluates phenotypic plasticity in stickleback body shape in response to salinity in fish stemming from a wild freshwater population. Using a split-clutch design, we detected surprisingly large phenotypically plastic changes in body shape after one generation. Fish raised in salt water developed shallower bodies and longer jaws, and these changes were consistent and parallel across families. Although this work highlights the effect of phenotypic plasticity, we also find indications that constraints may play a role in biasing the direction of possible phenotypic change. The slopes of the allometric relationship of individual linear traits did not change across treatments, indicating that plastic change does not affect the covariation of traits with overall size. We conclude that stickleback have a large capacity for plastic phenotypic change in response to salinity and that plasticity and evolutionary constraints have likely contributed to the phenotypic diversification of these fish.

  10. Direct ethanol production from hemicellulosic materials of rice straw by use of an engineered yeast strain codisplaying three types of hemicellulolytic enzymes on the surface of xylose-utilizing Saccharomyces cerevisiae cells.

    Science.gov (United States)

    Sakamoto, Takatoshi; Hasunuma, Tomohisa; Hori, Yoshimi; Yamada, Ryosuke; Kondo, Akihiko

    2012-04-30

    The cost of the lignocellulose-hydrolyzing enzymes used in the saccharification process of ethanol production from biomass accounts for a relatively high proportion of total processing costs. Cell surface engineering technology has facilitated a reduction in these costs by integrating saccharification and fermentation processes into a recombinant microbe strain expressing heterologous enzymes on the cell surface. We constructed a recombinant Saccharomyces cerevisiae that not only hydrolyzed hemicelluloses by codisplaying endoxylanase from Trichoderma reesei, β-xylosidase from Aspergillus oryzae, and β-glucosidase from Aspergillus aculeatus but that also assimilated xylose through the expression of xylose reductase and xylitol dehydrogenase from Pichia stipitis and xylulokinase from S. cerevisiae. The recombinant strain successfully produced ethanol from rice straw hydrolysate consisting of hemicellulosic material containing xylan, xylooligosaccharides, and cellooligosaccharides without requiring the addition of sugar-hydrolyzing enzymes or detoxication. The ethanol titer of the strain was 8.2g/l after 72h fermentation, which was approximately 2.5-fold higher than that of the control strain. The yield (grams of ethanol per gram of total sugars in rice straw hydrolysate consumed) was 0.41g/g, which corresponded to 82% of the theoretical yield. The cell surface-engineered strain was thus highly effective for consolidating the process of ethanol production from hemicellulosic materials.

  11. Testing the predictions of coping styles theory in threespined sticklebacks

    Science.gov (United States)

    Bensky, Miles K.; Paitz, Ryan; Pereira, Laura; Bell, Alison M.

    2017-01-01

    Coping styles theory provides a framework for understanding individual variation in how animals respond to environmental change, and predicts how individual differences in stress responsiveness and behavior might relate to cognitive differences. According to coping styles theory, proactive individuals are bolder, less reactive to stressors, and more routinized than their reactive counterparts. A key tenet of coping styles theory is that variation in coping styles is maintained by tradeoffs with behavioral flexibility: proactive individuals excel in stable environments while more flexible, reactive individuals perform better in variable environments. Here, we assess evidence for coping styles within a natural population of threespined sticklebacks (Gasterosteus aculeatus). We developed a criterion-based learning paradigm to evaluate individual variation in initial and reversal learning. We observed strong individual differences in boldness, cortisol production, and learning performance. Consistent with coping styles, fish that released more cortisol were more timid in response to a predator attack and slower to learn a color discrimination task. However, there was no evidence that reactive individuals performed better when the environment changed (when the rewarded color was reversed). The failure to detect trade-offs between behavioral routinization and flexibility prompts other explanations for the maintenance of differing coping styles. PMID:28017848

  12. Information flow through threespine stickleback networks without social transmission.

    Science.gov (United States)

    Atton, N; Hoppitt, W; Webster, M M; Galef, B G; Laland, K N

    2012-10-22

    Social networks can result in directed social transmission of learned information, thus influencing how innovations spread through populations. Here we presented shoals of threespine sticklebacks (Gasterosteous aculeatus) with two identical foraging tasks and applied network-based diffusion analysis (NBDA) to determine whether the order in which individuals in a social group contacted and solved the tasks was affected by the group's network structure. We found strong evidence for a social effect on discovery of the foraging tasks with individuals tending to discover a task sooner when others in their group had previously done so, and with the spread of discovery of the foraging tasks influenced by groups' social networks. However, the same patterns of association did not reliably predict spread of solution to the tasks, suggesting that social interactions affected the time at which the tasks were discovered, but not the latency to its solution following discovery. The present analysis, one of the first applications of NBDA to a natural animal system, illustrates how NBDA can lead to insight into the mechanisms supporting behaviour acquisition that more conventional statistical approaches might miss. Importantly, we provide the first compelling evidence that the spread of novel behaviours can result from social learning in the absence of social transmission, a phenomenon that we refer to as an untransmitted social effect on learning.

  13. The relationship between intraspecific assortative mating and reproductive isolation between divergent populations

    Directory of Open Access Journals (Sweden)

    Daniel I. BOLNICK, Mark KIRKPATRICK

    2012-06-01

    Full Text Available The term 'assortative mating' has been applied to describe two very different phenomena: (1 the tendency for individuals to choose phenotypically similar mates from among conspecifics; or (2 the tendency to prefer conspecific over hete- rospecific mates (behavioral reproductive isolation. Both forms of assortative mating are widespread in nature, but the relationship between these behaviors remains unclear. Namely, it is plausible that a preference for phenotypically similar conspecifics incidentally reduces the probability of mating with phenotypically divergent heterospecifics. We present a model to calculate how the level of reproductive isolation depends on intraspecific assortative mating and the phenotypic divergence between species. For empirically reasonable levels of intraspecific assortment on a single trait axis, we show that strong reproductive isolation requires very substantial phenotypic divergence. We illustrate this point by applying our model to empirical data from threespine stickleback Gasterosteus aculeatus and Darwin’s Finches (Geospiza spp. We conclude that typical levels of intraspecific assortment cannot generally be extrapolated to explain levels of interspecific reproductive isolation. Instead, reproductive isolation between species likely arises from different mate choice behaviors, or multivariate assortative mating [Current Zoology 58 (3: 481–489, 2012].

  14. Seasonal variation in parasite infection patterns of marine fish species from the Northern Wadden Sea in relation to interannual temperature fluctuations

    Science.gov (United States)

    Schade, Franziska M.; Raupach, Michael J.; Mathias Wegner, K.

    2016-07-01

    Marine environmental conditions are naturally changing throughout the year, affecting life cycles of hosts as well as parasites. In particular, water temperature is positively correlated with the development of many parasites and pathogenic bacteria, increasing the risk of infection and diseases during summer. Interannual temperature fluctuations are likely to alter host-parasite interactions, which may result in profound impacts on sensitive ecosystems. In this context we investigated the parasite and bacterial Vibrionaceae communities of four common small fish species (three-spined stickleback Gasterosteus aculeatus, Atlantic herring Clupea harengus, European sprat Sprattus sprattus and lesser sand eel Ammodytes tobianus) in the Northern Wadden Sea over a period of two years. Overall, we found significantly increased relative diversities of infectious species at higher temperature differentials. On the taxon-specific level some macroparasite species (trematodes, nematodes) showed a shift in infection peaks that followed the water temperatures of preceding months, whereas other parasite groups showed no effects of temperature differentials on infection parameters. Our results show that even subtle changes in seasonal temperatures may shift and modify the phenology of parasites as well as opportunistic pathogens that can have far reaching consequences for sensitive ecosystems.

  15. Morphological characterization and topographic analysis of multiple photoreceptor types in the retinae of mesopelagic hatchetfishes with tubular eyes

    Directory of Open Access Journals (Sweden)

    Lauren Michelle Biagioni

    2016-03-01

    Full Text Available Marine hatchetfishes, Argyropelecus spp., are one of the 14 genera of mesopelagic teleosts, which possess tubular eyes. The tubular eyes are positioned dorsally on the head and consist of a main retina, which subtends a large dorsal binocular field, and an accessory retina, which subtends the lateral monocular visual field. The topographic distribution of photoreceptors in the retina of Argyropelecus sladeni, A. affinis and A. aculeatus was determined using a random, unbiased and systematic stereological approach, which consistently revealed a region of high density (area centralis in the central region of the main retina (up to a peak of 96,000 receptors per mm2 and a relatively homogeneous density of photoreceptors in the accessory retina (of approximately 20,000 receptors per mm2. The position of the area centralis in the main retina indicates this retinal region subserves greater spatial resolution in the centre of the dorsal binocular visual field. Light microscopy and transmission electron microscopy also revealed the presence of multiple photoreceptor types (two rod-like and one cone-like based on the size and shape of the inner and outer segments and ultrastructural differences in the ellipsoidal region. The presence of multiple photoreceptor types in these tubular-eyed, mesopelagic hatchetfishes may reflect the need for the visual system to function under different lighting conditions during vertical migratory behavior, especially given their unique dorsally-facing eyes.

  16. Australian Marsh Beetles (Coleoptera: Scirtidae) 4. Two new genera, Austrocyphon and Tasmanocyphon.

    Science.gov (United States)

    Zwick, Peter

    2013-01-01

    The related new genera Austrocyphon and Tasmanocyphon are erected for 42 small Australian marsh beetles resembling members of the genus Cyphon Paykull in habitus. They are distinguished from Cyphon. Only males are known of most species but for two of them larvae and pupae are also available. Austrocyphon species occur in all Australian Federal States, and one species is Australasian and shared with Papua New Guinea. The following species are included: Austrocyphon acaciae sp. n., A. aculeatus sp. n., A. acustropicus sp. n., A. adelaidae (Blackburn), A. asper sp. n., A. bidens sp. n., A. bifidus sp. n., A. charon sp. n., A. crinitus (Klausnitzer), A. curvispina, sp. n., A. deserticola sp. n., A. doctus (Lea), A. enigmaticus sp. n., A. excisus sp. n., A. fenestratus (Blackburn), A. flagellifer sp. n., A. furcatus sp. n., A. hamatus sp. n., A. harpago sp. n., A. leptophallus sp. n., A. linguatus sp. n., A. lobatus sp. n., A. neptunus sp. n., A. noctua sp. n., A. ovensensis (Blackburn), A. papilio sp. n., A. perdoctus sp. n., A. pictus (Blackburn), A. quadridens sp. n., A. quinquespinosus sp. n., A. robustus sp. n., A. setifer sp. n., A. spiculifer sp. n., A. stylatus sp. n., A. stylifer sp. n., A. submersus sp. n., A. tinea sp. n., A. tomweiri sp. n., A. tribulator sp. n., A. tropicus sp. n., A. unguiculatus sp. n., A. wattsi sp. n.Tasmanocyphon is endemic to Tasmania, and only the adult male is known. The genus is monotypic, including only T. heideae, sp. n.

  17. Multivariate analisys of species from Cucurbitaceae family

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    Mladenović Emina

    2012-01-01

    Full Text Available Species from Cucurbitaceae family are not widely present in Serbia, although because of their morphological and decorative features deserve more attention. The aim of this paper was to study the morphological variability and usage of ten species of the Cucurbiataceae family. Based on genetic variability, species were grouped into 8 clusters. Fruit characteristics of most investigated species showed great similarity and the greatest differences were attained for flower and fruit characteristics. The longest was the fruit of Trichosanthes cucumerina (46.2 cm, while the shortest of Cucumis myriocarpus (3.4 cm which had the smallest circumference as well (4.4 cm. The largest circumference of fruit was recorded for the species Cucumis aculeatus (16.4 cm. In terms of fruit color Momordica balsamina had a red fruit, allocated from other species whose fruits were in various shades of green. Variability is reflected in large variations in size, shape and color of fruit. Considerating that usages of these species are multiple (food for humans and animals, ornamental studyed species deserve special attention in their further propagation and use.

  18. A common rule for decision making in animal collectives across species

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    Arganda, Sara; Pérez-Escudero, Alfonso; de Polavieja, Gonzalo G.

    2012-01-01

    A diversity of decision-making systems has been observed in animal collectives. In some species, choices depend on the differences of the numbers of animals that have chosen each of the available options, whereas in other species on the relative differences (a behavior known as Weber’s law), or follow more complex rules. We here show that this diversity of decision systems corresponds to a single rule of decision making in collectives. We first obtained a decision rule based on Bayesian estimation that uses the information provided by the behaviors of the other individuals to improve the estimation of the structure of the world. We then tested this rule in decision experiments using zebrafish (Danio rerio), and in existing rich datasets of argentine ants (Linepithema humile) and sticklebacks (Gasterosteus aculeatus), showing that a unified model across species can quantitatively explain the diversity of decision systems. Further, these results show that the different counting systems used by animals, including humans, can emerge from the common principle of using social information to make good decisions. PMID:23197836

  19. A Comparative BAC Map for the Gilthead Sea Bream (Sparus aurata L.

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    Heiner Kuhl

    2011-01-01

    Full Text Available This study presents the first comparative BAC map of the gilthead sea bream (Sparus aurata, a highly valuated marine aquaculture fish species in the Mediterranean. High-throughput end sequencing of a BAC library yielded 92,468 reads (60.6 Mbp. Comparative mapping was achieved by anchoring BAC end sequences to the three-spined stickleback (Gasterosteus aculeatus genome. BACs that were consistently ordered along the stickleback chromosomes accounted for 14,265 clones. A fraction of 5,249 BACs constituted a minimal tiling path that covers 73.5% of the stickleback chromosomes and 70.2% of the genes that have been annotated. The N50 size of 1,485 “BACtigs” consisting of redundant BACs is 337,253 bp. The largest BACtig covers 2.15 Mbp in the stickleback genome. According to the insert size distribution of mapped BACs the sea bream genome is 1.71-fold larger than the stickleback genome. These results represent a valuable tool to researchers in the field and may support future projects to elucidate the whole sea bream genome.

  20. Aquatic macroinvertebrate responses to native and non-native predators

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    Haddaway N. R.

    2014-01-01

    Full Text Available Non-native species can profoundly affect native ecosystems through trophic interactions with native species. Native prey may respond differently to non-native versus native predators since they lack prior experience. Here we investigate antipredator responses of two common freshwater macroinvertebrates, Gammarus pulex and Potamopyrgus jenkinsi, to olfactory cues from three predators; sympatric native fish (Gasterosteus aculeatus, sympatric native crayfish (Austropotamobius pallipes, and novel invasive crayfish (Pacifastacus leniusculus. G. pulex responded differently to fish and crayfish; showing enhanced locomotion in response to fish, but a preference for the dark over the light in response to the crayfish. P.jenkinsi showed increased vertical migration in response to all three predator cues relative to controls. These different responses to fish and crayfish are hypothesised to reflect the predators’ differing predation types; benthic for crayfish and pelagic for fish. However, we found no difference in response to native versus invasive crayfish, indicating that prey naiveté is unlikely to drive the impacts of invasive crayfish. The Predator Recognition Continuum Hypothesis proposes that benefits of generalisable predator recognition outweigh costs when predators are diverse. Generalised responses of prey as observed here will be adaptive in the presence of an invader, and may reduce novel predators’ potential impacts.

  1. Integration of an invasive consumer into an estuarine food web: direct and indirect effects of the New Zealand mud snail.

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    Brenneis, Valance E F; Sih, Andrew; de Rivera, Catherine E

    2011-09-01

    Introduced species interact both directly and indirectly with native species. We examine interactions between the introduced New Zealand mud snail (Potamopyrgus antipodarum) and native estuarine invertebrates and predators through experiments and field studies. A widely held management concern is that when P. antipodarum, which has low nutritional value, becomes abundant, it replaces nutritious prey in fish diets. We tested two key components of this view: (1) that fish consume, but get little direct nutritional value from P. antipodarum; and (2) that P. antipodarum has an indirect negative effect on fish by reducing the energy derived from native prey. We also examined predation by the native signal crayfish, Pacifastacus leniusculus. Laboratory feeding trials showed that both crayfish and fish consume P. antipodarum, a direct effect. Crayfish consumed and successfully digested higher numbers of snails than did fish [Pacific staghorn sculpin (Leptocottus armatus), three spine stickleback (Gasterosteus aculeatus), and juvenile starry flounder (Platicthys stellatus)]. P. antipodarum occurred at low frequencies in the stomachs of wild-caught fish. More interesting were the indirect effects of this invader, which ran counter to predictions. P. antipodarum presence was associated with no change or an increase in the amount of energy derived from native prey by predators. The presence of P. antipodarum also led to increased consumption of and preference for the native amphipod Americorophium salmonis over the native isopod Gnorimosphaeroma insulare. This is an example of short-term, asymmetric, apparent competition, in which the presence of one prey species (snails) increases predation on another prey species (the amphipod).

  2. Fish but Not Macroinvertebrates Promote Trophic Cascading Effects in High Density Submersed Plant Experimental Lake Food Webs in Two Contrasting Climate Regions

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    Carlos Iglesias

    2017-07-01

    Full Text Available Predators play a key role in the functioning of shallow lakes. Differences between the response of temperate and subtropical systems to fish predation have been proposed, but experimental evidence is scarce. To elucidate cascading effects produced by predators in contrasting climatic zones, we conducted a mesocosm experiment in three pairs of lakes in Uruguay and Denmark. We used two typical planktivorous-omnivorous fish species (Jenynsia multidentata + Cnesterodon decemmaculatus and Gasterosteus aculeatus + Perca fluviatilis and one littoral omnivorous-predatory macroinvertebrate (Palaemonetes argentinus and Gammarus lacustris, alone and combined, in numbers resembling natural densities. Fish predation on zooplankton increased phytoplankton biomass in both climate zones, whereas the effects of predatory macroinvertebrates on zooplankton and phytoplankton were not significant in either climate zone. Macroinvertebrates (that freely colonized the sampling devices were diminished by fish in both climate areas; however, periphyton biomass did not vary among treatments. Our experiments demonstrated that fish affected the structure of both planktonic and littoral herbivorous communities in both climate regions, with a visible positive cascading effect on phytoplankton biomass, but no effects on periphyton. Altogether, fish impacts appeared to be a strong driver of turbid water conditions in shallow lakes regardless of climatic zone by indirectly contributing to increasing phytoplankton biomass.

  3. Insights into the evolution of mammalian telomerase: Platypus TERT shares similarities with genes of birds and other reptiles and localizes on sex chromosomes

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    Hrdličková Radmila

    2012-06-01

    Full Text Available Abstract Background The TERT gene encodes the catalytic subunit of the telomerase complex and is responsible for maintaining telomere length. Vertebrate telomerase has been studied in eutherian mammals, fish, and the chicken, but less attention has been paid to other vertebrates. The platypus occupies an important evolutionary position, providing unique insight into the evolution of mammalian genes. We report the cloning of a platypus TERT (OanTERT ortholog, and provide a comparison with genes of other vertebrates. Results The OanTERT encodes a protein with a high sequence similarity to marsupial TERT and avian TERT. Like the TERT of sauropsids and marsupials, as well as that of sharks and echinoderms, OanTERT contains extended variable linkers in the N-terminal region suggesting that they were present already in basal vertebrates and lost independently in ray-finned fish and eutherian mammals. Several alternatively spliced OanTERT variants structurally similar to avian TERT variants were identified. Telomerase activity is expressed in all platypus tissues like that of cold-blooded animals and murine rodents. OanTERT was localized on pseudoautosomal regions of sex chromosomes X3/Y2, expanding the homology between human chromosome 5 and platypus sex chromosomes. Synteny analysis suggests that TERT co-localized with sex-linked genes in the last common mammalian ancestor. Interestingly, female platypuses express higher levels of telomerase in heart and liver tissues than do males. Conclusions OanTERT shares many features with TERT of the reptilian outgroup, suggesting that OanTERT represents the ancestral mammalian TERT. Features specific to TERT of eutherian mammals have, therefore, evolved more recently after the divergence of monotremes.

  4. Mechanisms and evolutionary patterns of mammalian and avian dosage compensation.

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    Philippe Julien

    Full Text Available As a result of sex chromosome differentiation from ancestral autosomes, male mammalian cells only contain one X chromosome. It has long been hypothesized that X-linked gene expression levels have become doubled in males to restore the original transcriptional output, and that the resulting X overexpression in females then drove the evolution of X inactivation (XCI. However, this model has never been directly tested and patterns and mechanisms of dosage compensation across different mammals and birds generally remain little understood. Here we trace the evolution of dosage compensation using extensive transcriptome data from males and females representing all major mammalian lineages and birds. Our analyses suggest that the X has become globally upregulated in marsupials, whereas we do not detect a global upregulation of this chromosome in placental mammals. However, we find that a subset of autosomal genes interacting with X-linked genes have become downregulated in placentals upon the emergence of sex chromosomes. Thus, different driving forces may underlie the evolution of XCI and the highly efficient equilibration of X expression levels between the sexes observed for both of these lineages. In the egg-laying monotremes and birds, which have partially homologous sex chromosome systems, partial upregulation of the X (Z in birds evolved but is largely restricted to the heterogametic sex, which provides an explanation for the partially sex-biased X (Z expression and lack of global inactivation mechanisms in these lineages. Our findings suggest that dosage reductions imposed by sex chromosome differentiation events in amniotes were resolved in strikingly different ways.

  5. Anterior commissure versus corpus callosum: A quantitative comparison across mammals.

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    Ashwell, Ken W S

    2016-04-01

    Mammals rely on two major pathways to transfer information between the two hemispheres of the brain: the anterior commissure and the corpus callosum. Metatheria and monotremes rely exclusively on the anterior commissure for interhemispheric transfer between the isocortices and olfactory allocortices of each side, whereas Eutheria use a combination of the anterior commissure and an additional pathway exclusive to Eutheria, the corpus callosum. Midline cross-sectional area of the anterior commissure and corpus callosum were measured in a range of mammals from all three infraclasses and plotted against brain volume to determine how midline anterior commissure area and its size relative to the corpus callosum vary with brain size and taxon. In Metatheria, the square root of anterior commissure area rises in almost direct proportion with the cube root of brain volume (i.e. the ratio of the two is relatively constant), whereas among Eutheria the ratio of the square root of anterior commissure area to the cube root of brain volume declines slightly with increasing brain size. The total of isocortical and olfactory allocortical commissure area rises more rapidly with increasing brain volume among Eutheria than among Metatheria. This means that the midline isocortical and olfactory allocortical commissural area of metatherians with large brains (about 70 ml) is only about 50% of that among eutherians with similarly sized brains. On the other hand, isocortical and olfactory allocortical commissural area is similar in Metatheria and Eutheria at brain volumes around 1 ml. Among the Eutheria, some groups make less use of the anterior commissure pathway than do others: soricomorphs, rodents and cetaceans have smaller anterior commissures for their brain size than do afrosoricids, erinaceomorphs and proboscideans. The findings suggest that use of the anterior commissural route for isocortical commissural connections may have placed limitations on interhemispheric transfer of

  6. Postembryonic Nephrogenesis and Persistence of Six2-Expressing Nephron Progenitor Cells in the Reptilian Kidney.

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    Troy Camarata

    Full Text Available New nephron formation (nephrogenesis ceases in mammals around birth and is completely absent in adults. In contrast, postembryonic nephrogenesis is well documented in the mesonephric kidneys of fishes and amphibians. The transient mesonephros in reptiles (including birds and mammals is replaced by the metanephros during embryogenesis. Thus, one may speculate that postembryonic nephrogenesis is restricted to the mesonephric kidney. Previous reports have suggested the metanephros of non-avian reptiles (hereafter reptiles may continually form nephrons throughout life. We investigated the presence of adult nephrogenesis in reptiles by examining adult kidneys from several species including Trachemys scripta, Chrysemys picta, Boa constrictor, Tupinambis tegu, Anolis carolinensis, and Alligator mississipiensis among others. We found that all major reptilian groups (Testudines, Crocodylia, and Squamates showed the presence of adult nephrogenesis. The total amount of nephrogenesis varied greatly between species with turtles displaying the highest density of nephrogenesis. In contrast, we were unable to detect adult nephrogenesis in monotremes, and in the iguanid A. carolinensis. Nephron progenitor cells express the transcription factor Six2, which in mammals, becomes downregulated as the progenitor cell population is exhausted and nephrogenesis ends. Using the alligator as a model, we were able to detect Six2-positive cap mesenchyme cells in the adult kidney, which spatially correlated with areas of nephrogenesis. These results suggest that the metanephric kidney of reptiles has maintained the ability to continually grow new nephrons during postembryonic life, a process lost early in mammalian evolution, likely due to the persistence of a Six2-expressing progenitor cell population.

  7. Independent evolution of transcriptional inactivation on sex chromosomes in birds and mammals.

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    Livernois, Alexandra M; Waters, Shafagh A; Deakin, Janine E; Marshall Graves, Jennifer A; Waters, Paul D

    2013-01-01

    X chromosome inactivation in eutherian mammals has been thought to be tightly controlled, as expected from a mechanism that compensates for the different dosage of X-borne genes in XX females and XY males. However, many X genes escape inactivation in humans, inactivation of the X in marsupials is partial, and the unrelated sex chromosomes of monotreme mammals have incomplete and gene-specific inactivation of X-linked genes. The bird ZW sex chromosome system represents a third independently evolved amniote sex chromosome system with dosage compensation, albeit partial and gene-specific, via an unknown mechanism (i.e. upregulation of the single Z in females, down regulation of one or both Zs in males, or a combination). We used RNA-fluorescent in situ hybridization (RNA-FISH) to demonstrate, on individual fibroblast cells, inactivation of 11 genes on the chicken Z and 28 genes on the X chromosomes of platypus. Each gene displayed a reproducible frequency of 1Z/1X-active and 2Z/2X-active cells in the homogametic sex. Our results indicate that the probability of inactivation is controlled on a gene-by-gene basis (or small domains) on the chicken Z and platypus X chromosomes. This regulatory mechanism must have been exapted independently to the non-homologous sex chromosomes in birds and mammals in response to an over-expressed Z or X in the homogametic sex, highlighting the universal importance that (at least partial) silencing plays in the evolution on amniote dosage compensation and, therefore, the differentiation of sex chromosomes.

  8. [Presence in a rodent of Chili of the nematode Inglamidinae (sub. fam. nov.) belonging to Amidostomatidae, a family known to be found in mammals of Australia].

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    Durette-Desset, M C; Denke, M A; Murua, R

    1976-01-01

    The Inglamidinae n. sub-fam., a new sub-family of Amidostomatidae from chilean Cricetidae is described with Inglamidum akodon gen. et sp. n. as the type genus and species. Out of the 23 Akodon captured in the same area, three samples of this nematode have been collected from two different species. These findings confirm that we are dealing with a well-adapted parasite and exclude the possibility of a fortuitous catch or an accidental transfer. This family displays two significant groups of taxonomic characters, including archaic characters such as cephalic structures which unite them to the Amidostomatidae, and on the other hand some more recently elaborated characters such as monodelphism and shape of synlophe and spicules which relate them to the Heligmosoms and more significantly to the line Viannaia-Viannella parasite of South-American Marsupials. We interpret this species as a "parasite of capture" and we assume that very similar species might occur in other endemic Mammals, mostly Marsupials. On a paleobiogeographical point of view this interpretation would make due allowance for postulating that the Amidostomatidae from Mammals have originated during the Secondary concurrently with the Marsupial expansion. These ancestral Nematodes would have given birth to the other Trichostrongyloidea through reduction of buccal cavity, and to the Ancylostomatoidea by further elaboration of buccal apparatus. Contrary to Inglis's hypothesis we are in favour of the genera Globocephaloides and Hypodontus to be assigned to the Globocephalinae and Uncinariinae (Ancylostomatidae) respectively, rather than to the Amidostomatidae. The occurrence of an Amidostomatidae in a South American Cricetidae is somewhat quite unexpected, mostly because this family is known to occur from australian Mammals only and also because the parasited Mammals are the most primitive of the group (Monotremes and Marsupials).

  9. Chromosomal gene movements reflect the recent origin and biology of therian sex chromosomes.

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    Lukasz Potrzebowski

    2008-04-01

    Full Text Available Mammalian sex chromosomes stem from ancestral autosomes and have substantially differentiated. It was shown that X-linked genes have generated duplicate intronless gene copies (retrogenes on autosomes due to this differentiation. However, the precise driving forces for this out-of-X gene "movement" and its evolutionary onset are not known. Based on expression analyses of male germ-cell populations, we here substantiate and extend the hypothesis that autosomal retrogenes functionally compensate for the silencing of their X-linked housekeeping parental genes during, but also after, male meiotic sex chromosome inactivation (MSCI. Thus, sexually antagonistic forces have not played a major role for the selective fixation of X-derived gene copies in mammals. Our dating analyses reveal that although retrogenes were produced ever since the common mammalian ancestor, selectively driven retrogene export from the X only started later, on the placental mammal (eutherian and marsupial (metatherian lineages, respectively. Together, these observations suggest that chromosome-wide MSCI emerged close to the eutherian-marsupial split approximately 180 million years ago. Given that MSCI probably reflects the spread of the recombination barrier between the X and Y, crucial for their differentiation, our data imply that these chromosomes became more widely differentiated only late in the therian ancestor, well after the divergence of the monotreme lineage. Thus, our study also provides strong independent support for the recent notion that our sex chromosomes emerged, not in the common ancestor of all mammals, but rather in the therian ancestor, and therefore are much younger than previously thought.

  10. Design and implementation of degenerate microsatellite primers for the mammalian clade.

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    Emmanuel Buschiazzo

    Full Text Available Microsatellites are popular genetic markers in molecular ecology, genetic mapping and forensics. Unfortunately, despite recent advances, the isolation of de novo polymorphic microsatellite loci often requires expensive and intensive groundwork. Primers developed for a focal species are commonly tested in a related, non-focal species of interest for the amplification of orthologous polymorphic loci; when successful, this approach significantly reduces cost and time of microsatellite development. However, transferability of polymorphic microsatellite loci decreases rapidly with increasing evolutionary distance, and this approach has shown its limits. Whole genome sequences represent an under-exploited resource to develop cross-species primers for microsatellites. Here we describe a three-step method that combines a novel in silico pipeline that we use to (1 identify conserved microsatellite loci from a multiple genome alignments, (2 design degenerate primer pairs, with (3 a simple PCR protocol used to implement these primers across species. Using this approach we developed a set of primers for the mammalian clade. We found 126,306 human microsatellites conserved in mammalian aligned sequences, and isolated 5,596 loci using criteria based on wide conservation. From a random subset of ~1000 dinucleotide repeats, we designed degenerate primer pairs for 19 loci, of which five produced polymorphic fragments in up to 18 mammalian species, including the distinctly related marsupials and monotremes, groups that diverged from other mammals 120-160 million years ago. Using our method, many more cross-clade microsatellite loci can be harvested from the currently available genomic data, and this ability is set to improve exponentially as further genomes are sequenced.

  11. On the haptic nature of the active electric sense of fish.

    Science.gov (United States)

    Caputi, Angel A; Aguilera, Pedro A; Carolina Pereira, Ana; Rodríguez-Cattáneo, Alejo

    2013-11-06

    Electroreception is a sensory modality present in chondrichthyes, actinopterygii, amphibians, and mammalian monotremes. The study of this non-intuitive sensory modality has provided insights for better understanding of sensory systems in general and inspired the development of innovative artificial devices. Here we review evidence obtained from the analysis of electrosensory images, neurophysiological data from the recording of unitary activity in the electrosensory lobe, and psychophysical data from analysis of novelty responses provoked in well-defined stimulus conditions, which all confirm that active electroreception has a short range, and that the influence of exploratory movements on object identification is strong. In active electric images two components can be identified: a "global" image profile depending on the volume, shape and global impedance of an object and a "texture" component depending on its surface attributes. There is a short range of the active electric sense and the progressive "blurring" of object image with distance. Consequently, the lack of precision regarding object location, considered together, challenge the current view of this sense as serving long range electrolocation and the commonly used metaphor of "electric vision". In fact, the active electric sense shares more commonalities with human active touch than with teleceptive senses as vision or audition. Taking into account that other skin exteroceptors and proprioception may be congruently stimulated during fish exploratory movements we propose that electric, mechanoceptive and proprioceptive sensory modalities found in electric fish could be considered together as a single haptic sensory system. This article is part of a Special Issue entitled Neural Coding 2012. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Independent evolution of transcriptional inactivation on sex chromosomes in birds and mammals.

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    Alexandra M Livernois

    Full Text Available X chromosome inactivation in eutherian mammals has been thought to be tightly controlled, as expected from a mechanism that compensates for the different dosage of X-borne genes in XX females and XY males. However, many X genes escape inactivation in humans, inactivation of the X in marsupials is partial, and the unrelated sex chromosomes of monotreme mammals have incomplete and gene-specific inactivation of X-linked genes. The bird ZW sex chromosome system represents a third independently evolved amniote sex chromosome system with dosage compensation, albeit partial and gene-specific, via an unknown mechanism (i.e. upregulation of the single Z in females, down regulation of one or both Zs in males, or a combination. We used RNA-fluorescent in situ hybridization (RNA-FISH to demonstrate, on individual fibroblast cells, inactivation of 11 genes on the chicken Z and 28 genes on the X chromosomes of platypus. Each gene displayed a reproducible frequency of 1Z/1X-active and 2Z/2X-active cells in the homogametic sex. Our results indicate that the probability of inactivation is controlled on a gene-by-gene basis (or small domains on the chicken Z and platypus X chromosomes. This regulatory mechanism must have been exapted independently to the non-homologous sex chromosomes in birds and mammals in response to an over-expressed Z or X in the homogametic sex, highlighting the universal importance that (at least partial silencing plays in the evolution on amniote dosage compensation and, therefore, the differentiation of sex chromosomes.

  13. A cross-species comparison of escape from X inactivation in Eutheria: implications for evolution of X chromosome inactivation.

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    Al Nadaf, Shafagh; Deakin, Janine E; Gilbert, Clément; Robinson, Terence J; Graves, Jennifer A M; Waters, Paul D

    2012-02-01

    Sex chromosome dosage compensation in both eutherian and marsupial mammals is achieved by X chromosome inactivation (XCI)--transcriptional repression that silences one of the two X chromosomes in the somatic cells of females. We recently used RNA fluorescent in situ hybridization (FISH) to show, in individual nuclei, that marsupial X inactivation (in the absence of XIST) occurs on a gene-by-gene basis, and that escape from inactivation is stochastic and independent of gene location. In the absence of similar data from fibroblast cell lines of eutherian representatives, a meaningful comparison is lacking. We therefore used RNA-FISH to examine XCI in fibroblast cell lines obtained from three distantly related eutherian model species: African savannah elephant (Loxodonta africana), mouse (Mus musculus) and human (Homo sapiens). We show that, unlike the orthologous marsupial X, inactivation of the X conserved region (XCR) in eutherians generally is complete. Two-colour RNA-FISH on female human, mouse and elephant interphase nuclei showed that XCR loci have monoallelic expression in almost all nuclei. However, we found that many loci located in the evolutionarily distinct recently added region (XAR) displayed reproducible locus-specific frequencies of nuclei with either one or two active X alleles. We propose that marsupial XCI retains features of an ancient incomplete silencing mechanism that was augmented by the evolution of the XIST gene that progressively stabilized the eutherian XCR. In contrast, the recently added region of the eutherian X displays an incomplete inactivation profile similar to that observed on the evolutionarily distinct marsupial X and the independently evolved monotreme X chromosomes.

  14. Ancient exaptation of a CORE-SINE retroposon into a highly conserved mammalian neuronal enhancer of the proopiomelanocortin gene.

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    Andrea M Santangelo

    2007-10-01

    Full Text Available The proopiomelanocortin gene (POMC is expressed in the pituitary gland and the ventral hypothalamus of all jawed vertebrates, producing several bioactive peptides that function as peripheral hormones or central neuropeptides, respectively. We have recently determined that mouse and human POMC expression in the hypothalamus is conferred by the action of two 5' distal and unrelated enhancers, nPE1 and nPE2. To investigate the evolutionary origin of the neuronal enhancer nPE2, we searched available vertebrate genome databases and determined that nPE2 is a highly conserved element in placentals, marsupials, and monotremes, whereas it is absent in nonmammalian vertebrates. Following an in silico paleogenomic strategy based on genome-wide searches for paralog sequences, we discovered that opossum and wallaby nPE2 sequences are highly similar to members of the superfamily of CORE-short interspersed nucleotide element (SINE retroposons, in particular to MAR1 retroposons that are widely present in marsupial genomes. Thus, the neuronal enhancer nPE2 originated from the exaptation of a CORE-SINE retroposon in the lineage leading to mammals and remained under purifying selection in all mammalian orders for the last 170 million years. Expression studies performed in transgenic mice showed that two nonadjacent nPE2 subregions are essential to drive reporter gene expression into POMC hypothalamic neurons, providing the first functional example of an exapted enhancer derived from an ancient CORE-SINE retroposon. In addition, we found that this CORE-SINE family of retroposons is likely to still be active in American and Australian marsupial genomes and that several highly conserved exonic, intronic and intergenic sequences in the human genome originated from the exaptation of CORE-SINE retroposons. Together, our results provide clear evidence of the functional novelties that transposed elements contributed to their host genomes throughout evolution.

  15. A Polychaete's powerful punch: venom gland transcriptomics of Glycera reveals a complex cocktail of toxin homologs.

    Science.gov (United States)

    von Reumont, Björn M; Campbell, Lahcen I; Richter, Sandy; Hering, Lars; Sykes, Dan; Hetmank, Jörg; Jenner, Ronald A; Bleidorn, Christoph

    2014-09-05

    Glycerids are marine annelids commonly known as bloodworms. Bloodworms have an eversible proboscis adorned with jaws connected to venom glands. Bloodworms prey on invertebrates, and it is known that the venom glands produce compounds that can induce toxic effects in animals. Yet, none of these putative toxins has been characterized on a molecular basis. Here we present the transcriptomic profiles of the venom glands of three species of bloodworm, Glycera dibranchiata, Glycera fallax and Glycera tridactyla, as well as the body tissue of G. tridactyla. The venom glands express a complex mixture of transcripts coding for putative toxin precursors. These transcripts represent 20 known toxin classes that have been convergently recruited into animal venoms, as well as transcripts potentially coding for Glycera-specific toxins. The toxins represent five functional categories: Pore-forming and membrane-disrupting toxins, neurotoxins, protease inhibitors, other enzymes, and CAP domain toxins. Many of the transcripts coding for putative Glycera toxins belong to classes that have been widely recruited into venoms, but some are homologs of toxins previously only known from the venoms of scorpaeniform fish and monotremes (stonustoxin-like toxin), turrid gastropods (turripeptide-like peptides), and sea anemones (gigantoxin I-like neurotoxin). This complex mixture of toxin homologs suggests that bloodworms employ venom while predating on macroscopic prey, casting doubt on the previously widespread opinion that G. dibranchiata is a detritivore. Our results further show that researchers should be aware that different assembly methods, as well as different methods of homology prediction, can influence the transcriptomic profiling of venom glands. © The Author(s) 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  16. A Polychaete’s Powerful Punch: Venom Gland Transcriptomics of Glycera Reveals a Complex Cocktail of Toxin Homologs

    Science.gov (United States)

    von Reumont, Björn M.; Richter, Sandy; Hering, Lars; Sykes, Dan; Hetmank, Jörg; Jenner, Ronald A.; Bleidorn, Christoph

    2014-01-01

    Glycerids are marine annelids commonly known as bloodworms. Bloodworms have an eversible proboscis adorned with jaws connected to venom glands. Bloodworms prey on invertebrates, and it is known that the venom glands produce compounds that can induce toxic effects in animals. Yet, none of these putative toxins has been characterized on a molecular basis. Here we present the transcriptomic profiles of the venom glands of three species of bloodworm, Glycera dibranchiata, Glycera fallax and Glycera tridactyla, as well as the body tissue of G. tridactyla. The venom glands express a complex mixture of transcripts coding for putative toxin precursors. These transcripts represent 20 known toxin classes that have been convergently recruited into animal venoms, as well as transcripts potentially coding for Glycera-specific toxins. The toxins represent five functional categories: Pore-forming and membrane-disrupting toxins, neurotoxins, protease inhibitors, other enzymes, and CAP domain toxins. Many of the transcripts coding for putative Glycera toxins belong to classes that have been widely recruited into venoms, but some are homologs of toxins previously only known from the venoms of scorpaeniform fish and monotremes (stonustoxin-like toxin), turrid gastropods (turripeptide-like peptides), and sea anemones (gigantoxin I-like neurotoxin). This complex mixture of toxin homologs suggests that bloodworms employ venom while predating on macroscopic prey, casting doubt on the previously widespread opinion that G. dibranchiata is a detritivore. Our results further show that researchers should be aware that different assembly methods, as well as different methods of homology prediction, can influence the transcriptomic profiling of venom glands. PMID:25193302

  17. Losses of functional opsin genes, short-wavelength cone photopigments, and color vision--a significant trend in the evolution of mammalian vision.

    Science.gov (United States)

    Jacobs, Gerald H

    2013-03-01

    All mammalian cone photopigments are derived from the operation of representatives from two opsin gene families (SWS1 and LWS in marsupial and eutherian mammals; SWS2 and LWS in monotremes), a process that produces cone pigments with respective peak sensitivities in the short and middle-to-long wavelengths. With the exception of a number of primate taxa, the modal pattern for mammals is to have two types of cone photopigment, one drawn from each of the gene families. In recent years, it has been discovered that the SWS1 opsin genes of a widely divergent collection of eutherian mammals have accumulated mutational changes that render them nonfunctional. This alteration reduces the retinal complements of these species to a single cone type, thus rendering ordinary color vision impossible. At present, several dozen species from five mammalian orders have been identified as falling into this category, but the total number of mammalian species that have lost short-wavelength cones in this way is certain to be much larger, perhaps reaching as high as 10% of all species. A number of circumstances that might be used to explain this widespread cone loss can be identified. Among these, the single consistent fact is that the species so affected are nocturnal or, if they are not technically nocturnal, they at least feature retinal organizations that are typically associated with that lifestyle. At the same time, however, there are many nocturnal mammals that retain functional short-wavelength cones. Nocturnality thus appears to set the stage for loss of functional SWS1 opsin genes in mammals, but it cannot be the sole circumstance.

  18. Non-coding RNAs and the acquisition of genomic imprinting in mammals

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Genomic imprinting,representing parent-specific expression of alleles at a locus,is mainly evident in flowering plants and placental mammals.Most imprinted genes,including numerous non-coding RNAs,are located in clusters regulated by imprinting control regions(ICRs).The acquisition and evolution of genomic imprinting is among the most fundamental genetic questions.Discoveries about the transition of mammalian imprinted gene domains from their non-imprinted ancestors,especially recent studies undertaken on the most ancient mammalian clades-the marsupials and monotremes from which model species genomes have recently been sequenced,are of high value.By reviewing and analyzing these studies,a close connection between non-coding RNAs and the acquisition of genomic imprinting in mammals is demonstrated.The evidence comes from two observations accompanied with the acquisition of the imprinting:(i) many novel non-coding RNA genes emerged in imprinted regions;(ii) the expressions of some conserved non-coding RNAs have changed dramatically.Furthermore,a systematical analysis of imprinted snoRNA(small nucleolar RNA) genes from 15 vertebrates suggests that the origination of imprinted snoRNAs occurred after the divergence between eutherians and marsupials,followed by a rapid expansion leading to the fixation of major gene families in the eutherian ancestor prior to the radiation of modern placental mammals.Involved in the regulation of imprinted silencing and mediating the chromatins epigenetic modification may be the major roles that non-coding RNAs play during the acquisition of genomic imprinting in mammals.

  19. Phylogeny of whey acidic protein (WAP) four-disulfide core proteins and their role in lower vertebrates and invertebrates.

    Science.gov (United States)

    Smith, Valerie J

    2011-10-01

    Proteins containing WAP (whey acidic protein) domains with a characteristic WFDC (WAP four-disulfide core) occur not only in mammals (including marsupials and monotremes) but also in birds, reptiles, amphibians and fish. In addition, they are present in numerous invertebrates, from cnidarians to urochordates. Many of those from non-mammalian groups are poorly understood with respect to function or phylogeny. Those well characterized so far are waprins from snakes, perlwapins from bivalves and crustins from decapod crustaceans. Waprins are venom proteins with a single WAP domain at the C-terminus. They display antimicrobial, rather than proteinase inhibitory, activities. Perlwapins, in contrast, possess three WAP domains at the C-terminus and are expressed in the shell nacre of abalones. They participate in shell formation by inhibiting the growth of calcium crystals in the shell. The crustin group is the largest of all WFDC-containing proteins in invertebrates with the vast majority being highly expressed in the haemocytes. Most have a single WAP domain at the C-terminus. The presence and type of the domains between the signal sequence and the C-terminus WAP domain separate the different crustin types. Most of the Type I and II crustins are antimicrobial towards Gram-positive bacteria, whereas the Type III crustins tend to display protease inhibition. Expression studies show that at least some crustins have other important biological effects, as levels change with physiological stress, wound repair, tissue regeneration or ecdysis. Thus WAP domains are widely distributed and highly conserved, serving in diverse physiological processes (proteinase inhibition, bacterial killing or inhibition of calcium transport).

  20. Epidermal sensory organs of moles, shrew moles, and desmans: a study of the family talpidae with comments on the function and evolution of Eimer's organ.

    Science.gov (United States)

    Catania, K C

    2000-09-01

    The epidermal sensory organs of members of the family Talpidae (moles, shrew-moles, and desmans) were investigated and compared to determine the range of sensory specializations and better understand how they evolved. Small domed mechanosensory organs called 'Eimer's organs' were present on the rhinarium of nearly all species of talpids, but not among the sister group of shrews (Soricidae) or other insectivore families. This suggests that the common ancestor to the talpids possessed Eimer's organs. Two species of moles from the driest habitats did not exhibit Eimer's organs - suggesting that their sensory organs degenerated in response to harsh, abrasive soil conditions. The semi-aquatic desmans uniquely possessed tiny sensory hairs interspersed with their Eimer's organs; these may act to sense water currents. Some species exhibited a subdivided, star-like, rhinarium - resembling an early embryonic stage of the star-nosed mole and providing clues to the evolution of the star. A single genera (Uropsilus) that branched off early in the evolution of the talpids had Eimer's organ-like structures but lacked some typical components. These findings fill a major gap in our knowledge of talpid sensory biology and suggest (1) how Eimer's organs evolved, (2) how the unusual appendages of the star-nosed mole evolved, (3) that the evolution of Eimer's organ is convergent with the mechanosensory push-rod of monotremes. The results also demonstrate the features that distinguish Eimer's organ from similar configurations of sensory receptors in other mammalian skin surfaces. Finally, a mechanism for Eimer's organ function in detecting object and prey specific surface features is proposed.

  1. Evolution of the Antisense Overlap between Genes for Thyroid Hormone Receptor and Rev-erbα and Characterization of an Exonic G-Rich Element That Regulates Splicing of TRα2 mRNA.

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    Stephen H Munroe

    Full Text Available The α-thyroid hormone receptor gene (TRα codes for two functionally distinct proteins: TRα1, the α-thyroid hormone receptor; and TRα2, a non-hormone-binding variant. The final exon of TRα2 mRNA overlaps the 3' end of Rev-erbα mRNA, which encodes another nuclear receptor on the opposite strand of DNA. To understand the evolution of this antisense overlap, we sequenced these genes and mRNAs in the platypus Orthorhynchus anatinus. Despite its strong homology with other mammals, the platypus TRα/Rev-erbα locus lacks elements essential for expression of TRα2. Comparative analysis suggests that alternative splicing of TRα2 mRNA expression evolved in a stepwise fashion before the divergence of eutherian and marsupial mammals. A short G-rich element (G30 located downstream of the alternative 3'splice site of TRα2 mRNA and antisense to the 3'UTR of Rev-erbα plays an important role in regulating TRα2 splicing. G30 is tightly conserved in eutherian mammals, but is absent in marsupials and monotremes. Systematic deletions and substitutions within G30 have dramatically different effects on TRα2 splicing, leading to either its inhibition or its enhancement. Mutations that disrupt one or more clusters of G residues enhance splicing two- to three-fold. These results suggest the G30 sequence can adopt a highly structured conformation, possibly a G-quadruplex, and that it is part of a complex splicing regulatory element which exerts both positive and negative effects on TRα2 expression. Since mutations that strongly enhance splicing in vivo have no effect on splicing in vitro, it is likely that the regulatory role of G30 is mediated through linkage of transcription and splicing.

  2. A second corticotropin-releasing hormone gene (CRH2) is conserved across vertebrate classes and expressed in the hindbrain of a basal neopterygian fish, the spotted gar (Lepisosteus oculatus).

    Science.gov (United States)

    Grone, Brian P; Maruska, Karen P

    2015-05-01

    To investigate the origins of the vertebrate stress-response system, we searched sequenced vertebrate genomes for genes resembling corticotropin-releasing hormone (CRH). We found that vertebrate genomes possess, in addition to CRH, another gene that resembles CRH in sequence and syntenic environment. This paralogous gene was previously identified only in the elephant shark (a holocephalan), but we find it also in marsupials, monotremes, lizards, turtles, birds, and fishes. We examined the relationship of this second vertebrate CRH gene, which we name CRH2, to CRH1 (previously known as CRH) and urocortin1/urotensin1 (UCN1/UTS1) in primitive fishes, teleosts, and tetrapods. The paralogs CRH1 and CRH2 likely evolved via duplication of CRH during a whole-genome duplication early in the vertebrate lineage. CRH2 was subsequently lost in both teleost fishes and eutherian mammals but retained in other lineages. To determine where CRH2 is expressed relative to CRH1 and UTS1, we used in situ hybridization on brain tissue from spotted gar (Lepisosteus oculatus), a neopterygian fish closely related to teleosts. In situ hybridization revealed widespread distribution of both crh1 and uts1 in the brain. Expression of crh2 was restricted to the putative secondary gustatory/secondary visceral nucleus, which also expressed calcitonin-related polypeptide alpha (calca), a marker of parabrachial nucleus in mammals. Thus, the evolutionary history of CRH2 includes restricted expression in the brain, sequence changes, and gene loss, likely reflecting release of selective constraints following whole-genome duplication. The discovery of CRH2 opens many new possibilities for understanding the diverse functions of the CRH family of peptides across vertebrates. © 2015 Wiley Periodicals, Inc.

  3. What lies beneath: sub-articular long bone shape scaling in eutherian mammals and saurischian dinosaurs suggests different locomotor adaptations for gigantism.

    Science.gov (United States)

    Bonnan, Matthew F; Wilhite, D Ray; Masters, Simon L; Yates, Adam M; Gardner, Christine K; Aguiar, Adam

    2013-01-01

    Eutherian mammals and saurischian dinosaurs both evolved lineages of huge terrestrial herbivores. Although significantly more saurischian dinosaurs were giants than eutherians, the long bones of both taxa scale similarly and suggest that locomotion was dynamically similar. However, articular cartilage is thin in eutherian mammals but thick in saurischian dinosaurs, differences that could have contributed to, or limited, how frequently gigantism evolved. Therefore, we tested the hypothesis that sub-articular bone, which supports the articular cartilage, changes shape in different ways between terrestrial mammals and dinosaurs with increasing size. Our sample consisted of giant mammal and reptile taxa (i.e., elephants, rhinos, sauropods) plus erect and non-erect outgroups with thin and thick articular cartilage. Our results show that eutherian mammal sub-articular shape becomes narrow with well-defined surface features as size increases. In contrast, this region in saurischian dinosaurs expands and remains gently convex with increasing size. Similar trends were observed in non-erect outgroup taxa (monotremes, alligators), showing that the trends we report are posture-independent. These differences support our hypothesis that sub-articular shape scales differently between eutherian mammals and saurischian dinosaurs. Our results show that articular cartilage thickness and sub-articular shape are correlated. In mammals, joints become ever more congruent and thinner with increasing size, whereas archosaur joints remained both congruent and thick, especially in sauropods. We suggest that gigantism occurs less frequently in mammals, in part, because joints composed of thin articular cartilage can only become so congruent before stress cannot be effectively alleviated. In contrast, frequent gigantism in saurischian dinosaurs may be explained, in part, by joints with thick articular cartilage that can deform across large areas with increasing load.

  4. What lies beneath: sub-articular long bone shape scaling in eutherian mammals and saurischian dinosaurs suggests different locomotor adaptations for gigantism.

    Directory of Open Access Journals (Sweden)

    Matthew F Bonnan

    Full Text Available Eutherian mammals and saurischian dinosaurs both evolved lineages of huge terrestrial herbivores. Although significantly more saurischian dinosaurs were giants than eutherians, the long bones of both taxa scale similarly and suggest that locomotion was dynamically similar. However, articular cartilage is thin in eutherian mammals but thick in saurischian dinosaurs, differences that could have contributed to, or limited, how frequently gigantism evolved. Therefore, we tested the hypothesis that sub-articular bone, which supports the articular cartilage, changes shape in different ways between terrestrial mammals and dinosaurs with increasing size. Our sample consisted of giant mammal and reptile taxa (i.e., elephants, rhinos, sauropods plus erect and non-erect outgroups with thin and thick articular cartilage. Our results show that eutherian mammal sub-articular shape becomes narrow with well-defined surface features as size increases. In contrast, this region in saurischian dinosaurs expands and remains gently convex with increasing size. Similar trends were observed in non-erect outgroup taxa (monotremes, alligators, showing that the trends we report are posture-independent. These differences support our hypothesis that sub-articular shape scales differently between eutherian mammals and saurischian dinosaurs. Our results show that articular cartilage thickness and sub-articular shape are correlated. In mammals, joints become ever more congruent and thinner with increasing size, whereas archosaur joints remained both congruent and thick, especially in sauropods. We suggest that gigantism occurs less frequently in mammals, in part, because joints composed of thin articular cartilage can only become so congruent before stress cannot be effectively alleviated. In contrast, frequent gigantism in saurischian dinosaurs may be explained, in part, by joints with thick articular cartilage that can deform across large areas with increasing load.

  5. Comparative aspects of gait, scaling and mechanics in mammals.

    Science.gov (United States)

    Gasc, J P

    2001-12-01

    In phylogenetically based systematics, Mammalia is the nomenclatural term which designates the clade stemming from the most recent common ancestry of monotremes and theria [, Sys. Biol. 43 (1994) 497]. Considering that locomotor performance is a prevalent function to provide the necessary conditions to survive and transmit genes, it may be questioned if the diverse types of locomotion exhibited by extant mammals could have played a role in their evolution, or have only followed it. We may look after the structural and behavioural features which are involved in mammal locomotion compared to other tetrapods and test if they fit with the proposed phylogeny. Several factors may be checked: scaling effect in relation to gravitational constraints; geometrical distribution of masses in the body, and relative mechanical role of the limbs in the production of the external forces necessary to forward motion. Classically, it was thought that the fastest gaits used by terrestrial mammals were based upon a unique kind of limb motion co-ordination, called asymmetrical gaits, which in turn may be thought to be related to a peculiar neuronal wiring. Kinematic analysis brings an insight to this topic. Is the search for an ancestral mammalian locomotor pattern judicious? Notice the small size of many of the first mammals and their probable locomotor plasticity. (relation between grain size of the elements within the substrate and the organism scale). At a small size, the gravitational constraint is less important, and the distinction between terrestrial and arboreal has probably no sense when the limbs are the principal motor elements. There remains the importance of the geometrical distribution of body elements, the proportions of the limbs and of the head-neck complex, the tail merely as an appendix, a set of factors which may have generated the frame of constraints within which diverse locomotor modes have evolved.

  6. Novel genotypes of Trypanosoma binneyi from wild platypuses (Ornithorhynchus anatinus) and identification of a leech as a potential vector.

    Science.gov (United States)

    Paparini, Andrea; Macgregor, James; Irwin, Peter J; Warren, Kristin; Ryan, Una M

    2014-10-01

    Little is known about the prevalence and pathogenesis of trypanosomes in Australian monotremes, and few genetic characterisation studies have been conducted with these haemoparasites. During the present investigation, molecular and microscopic methods were used to screen peripheral blood (n=28) and ectoparasites (n=10 adult ticks; n=5 tick nymphs; n=1 leech; and n>500 tick eggs) collected from wild Tasmanian platypuses (Ornithorhynchus anatinus), for the presence of trypanosomatid-specific DNA and/or trypomastigotes. The genes for the small ribosomal subunit RNA (18S rDNA) and glycosomal glyceraldehyde phosphate dehydrogenase (gGAPDH) were amplified and sequenced, prior to conducting phylogenetic analyses. The detection rate of the parasite-specific 18S rDNA in platypus blood was 85.7% (n=24/28), and the leech was also positive at both loci. Microscopically, high parasitaemia and the presence of abundant trypomastigotes, morphologically consistent with Trypanosoma binneyi Mackerras (1959), were observed in the blood films. Phylogenetic analyses at the 18S locus revealed the existence of four trypanosomatid-like genotypes, with variable similarity to two previously-described genotypes of T. binneyi (range of genetic p-distance: 0.0-0.5%). For the gGAPDH locus, for which only one T. binneyi sequence is available in GenBank, three genotypes closely related T. binneyi were identified (range of genetic p-distance: 0.1-0.4%). The leech-derived trypanosome isolate was virtually identical (at the two loci studied) to the other parasites sequenced from infected platypuses; however, the molecular or morphological identification of the leech species was not possible. Although further studies are required, the molecular detection of trypanosomes in an aquatic leech removed from a platypus, suggests the possibility that these haematophagous hirudineans may be a vector for T. binneyi (and closely related genotypes).

  7. An annotated distributional checklist of exotic freshwater fishes from the Baja California Peninsula, Mexico Lista comentada sobre la distribución de peces dulceacuícolas exóticos de la península de Baja California, México

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    Gorgonio Ruiz-Campos

    2012-03-01

    Full Text Available We documented the distributional status of 27 exotic fish species in the inland waters of the Baja California Peninsula, Mexico, based on voucher specimens collected from 122 sites between 1977 and 2010, and on published records. The species reported here are representatives of genera from the Atlantic drainages of North America (Ictalurus, Ameiurus, Pylodictis, Morone, Lepomis, Pomoxis, Dorosoma, Cyprinella, and Micropterus, Middle America (Poecilia, Gambusia, and Xiphophorus, Eurasia (Cyprinus and Carassius, and Africa (Tilapia and Oreochromis. The family containing the highest number of species is Centrarchidae (7 species followed by Ictaluridae and Poeciliidae (6 species each. Four species were determined to be invasive due to their wide distribution and fast dispersal through the Peninsula (Gambusia affinis, Poecilia reticulata, Lepomis cyanellus, and Tilapia sp. cf. zillii. We analyze the impacts of exotic species on the native populations of 3 species with problems of conservation: Cyprinodon macularius (endangered, Fundulus lima (endangered, and Gasterosteus aculeatus (vulnerable. Alien fishes have been introduced for a variety of reasons in Mexico: ornament, sport, aquaculture, biological control, and by accident. In some cases fish introductions were carried out for more than one reason.El estatus de la distribución de peces exóticos es documentado para 27 especies en las aguas continentales de la península de Baja California, México, basado en registros de ejemplares recolectados en 122 localidades durante el período de 1977 a 2010, así como registros referidos en la literatura. Las especies aquí reportadas son representativas de géneros que proceden de la vertiente Atlántica de Norteamérica (Ictalurus, Ameiurus, Pylodictis, Morone, Lepomis, Pomoxis, Dorosoma, Cyprinella y Micropterus, Mesoamérica (Poecilia, Gambusia y Xiphophorus, Eurasia (Cyprinus y Carassius y África (Tilapia y Oreochromis. La familia con mayor n

  8. STRUKTUR KOMUNITAS DAN RELUNG MAKANAN IKAN PASCA INTRODUKSI IKAN PATIN SIAM (Pangasianodon hypophthalmus DI WADUK MALAHAYU, KABUPATEN BREBES

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    Kunto Purnomo

    2016-06-01

    Full Text Available Studi tentang struktur komunitas ikan dan pembagian sumber daya pakan ikan pasca introduksi ikan patin siam (Pangasianodon hypophthalmus di Waduk Malahayu (620 ha dilakukan dengan tujuan untuk mengetahui komposisi jenis ikan, preferensi makanan, dan luas relung tiap jenis ikan. Penelitian dilaksanakan dengan menggunakan metode survei pada bulan Agustus sampai Nopember 2009 dan bulan Maret sampai Oktober 2010. Hasil penelitian menunjukkan bahwa struktur komunitas ikan terdiri atas 13 jenis ikan, yang didominansi oleh ikan nila (Oreochromis niloticus, udang (Macrobrachium sp., dan gabus (Channa striata. Jenis-jenis sumber daya pakan yang dimanfaatkan oleh ikan adalah fitoplankton (20%, detritus (19%, zooplankton (17%, insekta (11%, tumbuhan air (9%, ikan (9%, udang (9%, dan moluska (6%. Ikan patin siam, mujair (Oreochromis mossambicus, dan beunteur (Puntius binotatus bersifat generalis karena mampu memanfaatkan semua sumber daya pakan alami yang tersedia. Ikan sili (Macrognathus aculeatus dan keting (Mystus nigriceps lebih bersifat spesialis karena hanya memanfaatkan insekta sebagai makanan utamanya. Peluang kompetisi antara ikan patin siam (diintroduksikan tahun 2009 dan ikan nila relatif kecil sebab sumber daya pakan utamanya berbeda, yaitu ikan patin siam memanfaatkan moluska sebagai makanan utamanya sedangkan ikan nila sebagian memanfaatkan fitoplankton. Hasil tangkapan ikan di waduk ini berkisar antara 34,3-1.323,1 ton/tahun dengan rata-rata 157,3 ton/tahun.   Malahayu Reservoir located in Brebes Regency, was impounded in 1930, with a surface area of 620 hectares, a mean water depth of 8 m. Its main function are flood control and irrigation. Study on fish community structure and food resource partitioning of fishes in Malahayu Reservoir were conducted from August to November 2009 and March to October 2010. The aim of the study was to evaluate the existing condition of fish resources, with emphasis on species composition, food preferency, and

  9. Collective animal behavior from Bayesian estimation and probability matching.

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    Alfonso Pérez-Escudero

    2011-11-01

    Full Text Available Animals living in groups make movement decisions that depend, among other factors, on social interactions with other group members. Our present understanding of social rules in animal collectives is mainly based on empirical fits to observations, with less emphasis in obtaining first-principles approaches that allow their derivation. Here we show that patterns of collective decisions can be derived from the basic ability of animals to make probabilistic estimations in the presence of uncertainty. We build a decision-making model with two stages: Bayesian estimation and probabilistic matching. In the first stage, each animal makes a Bayesian estimation of which behavior is best to perform taking into account personal information about the environment and social information collected by observing the behaviors of other animals. In the probability matching stage, each animal chooses a behavior with a probability equal to the Bayesian-estimated probability that this behavior is the most appropriate one. This model derives very simple rules of interaction in animal collectives that depend only on two types of reliability parameters, one that each animal assigns to the other animals and another given by the quality of the non-social information. We test our model by obtaining theoretically a rich set of observed collective patterns of decisions in three-spined sticklebacks, Gasterosteus aculeatus, a shoaling fish species. The quantitative link shown between probabilistic estimation and collective rules of behavior allows a better contact with other fields such as foraging, mate selection, neurobiology and psychology, and gives predictions for experiments directly testing the relationship between estimation and collective behavior.

  10. Reproductive strategies and seasonal changes in the somatic indices of seven small-bodied fishes in Atlantic Canada in relation to study design for environmental effects monitoring.

    Science.gov (United States)

    Barrett, Timothy J; Brasfield, Sandra M; Carroll, Leslie C; Doyle, Meghan A; van den Heuvel, Michael R; Munkittrick, Kelly R

    2015-05-01

    Small-bodied fishes are more commonly being used in environmental effects monitoring (EEM) studies. There is a lack of understanding of the biological characteristics of many small-bodied species, which hinders study designs for monitoring studies. For example, 72% of fish population surveys in Canada's EEM program for pulp and paper mills that used small-bodied fishes were conducted outside of the reproductive period of the species. This resulted in an inadequate assessment of the EEM program's primary effect endpoint (reproduction) for these studies. The present study examined seasonal changes in liver size, gonad size, and condition in seven freshwater and estuarine small-bodied fishes in Atlantic Canada. These data were used to examine differences in reproductive strategies and patterns of energy storage among species. Female gonadal recrudescence in all seven species began primarily in the 2-month period in the spring before spawning. Male gonadal development was concurrent with females in five species; however, gonadal recrudescence began in the fall in male three-spined stickleback (Gasterosteus aculeatus) and slimy sculpin (Cottus cognatus). The spawning period for each species was estimated from the decline in relative ovary size after its seasonal maximum value in spring. The duration of the spawning period reflected the reproductive strategy (single vs multiple spawning) of the species. Optimal sampling periods to assess reproductive impacts in each species were determined based on seasonal changes in ovary size and were identified to be during the prespawning period when gonads are developing and variability in relative gonad size is at a minimum.

  11. Comparative morphology of changeable skin papillae in octopus and cuttlefish.

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    Allen, Justine J; Bell, George R R; Kuzirian, Alan M; Velankar, Sachin S; Hanlon, Roger T

    2014-04-01

    A major component of cephalopod adaptive camouflage behavior has rarely been studied: their ability to change the three-dimensionality of their skin by morphing their malleable dermal papillae. Recent work has established that simple, conical papillae in cuttlefish (Sepia officinalis) function as muscular hydrostats; that is, the muscles that extend a papilla also provide its structural support. We used brightfield and scanning electron microscopy to investigate and compare the functional morphology of nine types of papillae of different shapes, sizes and complexity in six species: S. officinalis small dorsal papillae, Octopus vulgaris small dorsal and ventral eye papillae, Macrotritopus defilippi dorsal eye papillae, Abdopus aculeatus major mantle papillae, O. bimaculoides arm, minor mantle, and dorsal eye papillae, and S. apama face ridge papillae. Most papillae have two sets of muscles responsible for extension: circular dermal erector muscles arranged in a concentric pattern to lift the papilla away from the body surface and horizontal dermal erector muscles to pull the papilla's perimeter toward its core and determine shape. A third set of muscles, retractors, appears to be responsible for pulling a papilla's apex down toward the body surface while stretching out its base. Connective tissue infiltrated with mucopolysaccharides assists with structural support. S. apama face ridge papillae are different: the contraction of erector muscles perpendicular to the ridge causes overlying tissues to buckle. In this case, mucopolysaccharide-rich connective tissue provides structural support. These six species possess changeable papillae that are diverse in size and shape, yet with one exception they share somewhat similar functional morphologies. Future research on papilla morphology, biomechanics and neural control in the many unexamined species of octopus and cuttlefish may uncover new principles of actuation in soft, flexible tissue.

  12. Application of Passive Sampling to Characterise the Fish Exometabolome

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    Mark R. Viant

    2017-02-01

    Full Text Available The endogenous metabolites excreted by organisms into their surrounding environment, termed the exometabolome, are important for many processes including chemical communication. In fish biology, such metabolites are also known to be informative markers of physiological status. While metabolomics is increasingly used to investigate the endogenous biochemistry of organisms, no non-targeted studies of the metabolic complexity of fish exometabolomes have been reported to date. In environmental chemistry, Chemcatcher® (Portsmouth, UK passive samplers have been developed to sample for micro-pollutants in water. Given the importance of the fish exometabolome, we sought to evaluate the capability of Chemcatcher® samplers to capture a broad spectrum of endogenous metabolites excreted by fish and to measure these using non-targeted direct infusion mass spectrometry metabolomics. The capabilities of C18 and styrene divinylbenzene reversed-phase sulfonated (SDB-RPS Empore™ disks for capturing non-polar and polar metabolites, respectively, were compared. Furthermore, we investigated real, complex metabolite mixtures excreted from two model fish species, rainbow trout (Oncorhynchus mykiss and three-spined stickleback (Gasterosteus aculeatus. In total, 344 biological samples and 28 QC samples were analysed, revealing 646 and 215 m/z peaks from trout and stickleback, respectively. The measured exometabolomes were principally affected by the type of Empore™ (Hemel Hempstead, UK disk and also by the sampling time. Many peaks were putatively annotated, including several bile acids (e.g., chenodeoxycholate, taurocholate, glycocholate, glycolithocholate, glycochenodeoxycholate, glycodeoxycholate. Collectively these observations show the ability of Chemcatcher® passive samplers to capture endogenous metabolites excreted from fish.

  13. Stepwise threshold clustering: a new method for genotyping MHC loci using next-generation sequencing technology.

    Directory of Open Access Journals (Sweden)

    William E Stutz

    Full Text Available Genes of the vertebrate major histocompatibility complex (MHC are of great interest to biologists because of their important role in immunity and disease, and their extremely high levels of genetic diversity. Next generation sequencing (NGS technologies are quickly becoming the method of choice for high-throughput genotyping of multi-locus templates like MHC in non-model organisms. Previous approaches to genotyping MHC genes using NGS technologies suffer from two problems:1 a "gray zone" where low frequency alleles and high frequency artifacts can be difficult to disentangle and 2 a similar sequence problem, where very similar alleles can be difficult to distinguish as two distinct alleles. Here were present a new method for genotyping MHC loci--Stepwise Threshold Clustering (STC--that addresses these problems by taking full advantage of the increase in sequence data provided by NGS technologies. Unlike previous approaches for genotyping MHC with NGS data that attempt to classify individual sequences as alleles or artifacts, STC uses a quasi-Dirichlet clustering algorithm to cluster similar sequences at increasing levels of sequence similarity. By applying frequency and similarity based criteria to clusters rather than individual sequences, STC is able to successfully identify clusters of sequences that correspond to individual or similar alleles present in the genomes of individual samples. Furthermore, STC does not require duplicate runs of all samples, increasing the number of samples that can be genotyped in a given project. We show how the STC method works using a single sample library. We then apply STC to 295 threespine stickleback (Gasterosteus aculeatus samples from four populations and show that neighboring populations differ significantly in MHC allele pools. We show that STC is a reliable, accurate, efficient, and flexible method for genotyping MHC that will be of use to biologists interested in a variety of downstream applications.

  14. The effect of octopaminergic compounds on the behaviour and transmission of Gyrodactylus

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    Bron James E

    2011-10-01

    Full Text Available Abstract Background The high transmission potential of species belonging to the monogenean parasite genus Gyrodactylus, coupled with their high fecundity, allows them to rapidly colonise new hosts and to increase in number. One gyrodactylid, Gyrodactylus salaris Malmberg, 1957, has been responsible for devastation of Altantic salmon (Salmo salar L. populations in a number of Norwegian rivers. Current methods of eradicating G. salaris from river systems centre around the use of non-specific biocides, such as rotenone and aluminium sulphate. Although transmission routes in gyrodactylids have been studied extensively, the behaviour of individual parasites has received little attention. Specimens of Gyrodactylus gasterostei Gläser, 1974 and G. arcuatus Bychowsky, 1933, were collected from the skin of their host, the three-spined stickleback (Gasterosteus aculeatus L., and permitted to attach to the substrate. The movements of individual parasites were recorded and analysed. Results The behaviour patterns of the two species were similar and parasites were more active in red light and darkness than in white light. Four octopaminergic compounds were tested and all four inhibited the movements of parasites. Treatment ultimately led to death at low concentrations (0.2 μM, although prolonged exposure was necessary in some instances. Conclusions Octopaminergic compounds may affect the parasite's ability to locate and remain on its host and these or related compounds might provide alternative or supplementary treatments for the control of G. salaris infections. With more research there is potential for use of octopaminergic compounds, which have minimal effects on the host or its environment, as parasite-specific treatments against G. salaris infections.

  15. Early growth trajectories affect sexual responsiveness.

    Science.gov (United States)

    Lee, Who-Seung; Metcalfe, Neil B; Réale, Denis; Peres-Neto, Pedro R

    2014-02-22

    The trajectory of an animal's growth in early development has been shown to have long-term effects on a range of life-history traits. Although it is known that individual differences in behaviour may also be related to certain life-history traits, the linkage between early growth or development and individual variation in behaviour has received little attention. We used brief temperature manipulations, independent of food availability, to stimulate compensatory growth in juvenile three-spined sticklebacks Gasterosteus aculeatus. Here, we examine how these manipulated growth trajectories affected the sexual responsiveness of the male fish at the time of sexual maturation, explore associations between reproductive behaviour and investment and lifespan and test whether the perceived time stress (until the onset of the breeding season) influenced such trade-offs. We found a negative impact of growth rate on sexual responsiveness: fish induced (by temperature manipulation) to grow slowest prior to the breeding season were consistently quickest to respond to the presence of a gravid female. This speed of sexual responsiveness was also positively correlated with the rate of development of sexual ornaments and time taken to build a nest. However, after controlling for effects of growth rate, those males that had the greatest sexual responsiveness to females had the shortest lifespan. Moreover, the time available to compensate in size before the onset of the breeding season (time stress) affected the magnitude of these effects. Our results demonstrate that developmental perturbations in early life can influence mating behaviour, with long-term effects on longevity.

  16. Soybean bio-refinery platform: enzymatic process for production of soy protein concentrate, soy protein isolate and fermentable sugar syrup.

    Science.gov (United States)

    Loman, Abdullah Al; Islam, S M Mahfuzul; Li, Qian; Ju, Lu-Kwang

    2016-10-01

    Soybean carbohydrate is often found to limit the use of protein in soy flour as food and animal feed due to its indigestibility to monogastric animal. In the current study, an enzymatic process was developed to produce not only soy protein concentrate and soy protein isolate without indigestible carbohydrate but also soluble reducing sugar as potential fermentation feedstock. For increasing protein content in the product and maximizing protein recovery, the process was optimized to include the following steps: hydrolysis of soy flour using an Aspergillus niger enzyme system; separation of the solid and liquid by centrifugation (10 min at 7500×g); an optional step of washing to remove entrapped hydrolysate from the protein-rich wet solid stream by ethanol (at an ethanol-to-wet-solid ratio (v/w) of 10, resulting in a liquid phase of approximately 60 % ethanol); and a final precipitation of residual protein from the sugar-rich liquid stream by heat treatment (30 min at 95 °C). Starting from 100 g soy flour, this process would produce approximately 54 g soy protein concentrate with 70 % protein (or, including the optional solid wash, 43 g with 80 % protein), 9 g soy protein isolate with 89 % protein, and 280 ml syrup of 60 g/l reducing sugar. The amino acid composition of the soy protein concentrate produced was comparable to that of the starting soy flour. Enzymes produced by three fungal species, A. niger, Trichoderma reesei, and Aspergillus aculeatus, were also evaluated for effectiveness to use in this process.

  17. Ultraviolet reflection enhances the risk of predation in a vertebrate

    Institute of Scientific and Technical Information of China (English)

    Ricarda MODARRESSIE; Ingolf P.RICK; Theo C.M.BAKKER

    2013-01-01

    Many animals are sensitive to ultraviolet light and also possess UV-reflective regions on their body surface.Individuals reflecting UV have been shown to be preferred during social interactions such as mate choice or shoaling decisions.However,whether those body UV-reflections enhance also the conspicuousness to UV-sensitive predators and therefore entail costs for its bearer is less well documented.Two size-matched three-spined sticklebacks Gasterosteus aculeatus,one enclosed in a UV-transmitting (UV+) and another in a UV-blocking (UV-) chamber,were simultaneously presented to individual brown trout Salmo trutta.“yearlings”.Brown trout of this age are sensitive to the UV part of the electromagnetic spectrum and are natural predators of three-spined sticklebacks.The stickleback that was attacked first as well as the subsequent number of attacks was recorded.Sticklebacks enclosed in the UV-transmitting chamber were attacked first significantly more often compared to sticklebacks enclosed in the UV-blocking chamber.Control experiments using neutral density filters revealed that this was more likely due to UV having an influence on hue perception rather than brightness discrimination.The difference in attack probability corresponded to the difference in chromatic contrasts between sticklebacks and the experimental background calculated for both the UV+ and UV-conditions in a physiological model of trout colour vision.UV reflections seem to be costly by enhancing the risk of predation due to an increased conspicuousness of prey.This is the first study in a vertebrate,to our knowledge,demonstrating direct predation risk due to UV wavelengths.

  18. Ultraviolet reflection enhances the risk of predation in a vertebrate

    Directory of Open Access Journals (Sweden)

    Ricarda MODARRESSIE, Ingolf P. RICK, Theo C. M. BAKKER

    2013-04-01

    Full Text Available Many animals are sensitive to ultraviolet light and also possess UV-reflective regions on their body surface. Individuals reflecting UV have been shown to be preferred during social interactions such as mate choice or shoaling decisions. However, whether those body UV-reflections enhance also the conspicuousness to UV-sensitive predators and therefore entail costs for its bearer is less well documented. Two size-matched three-spined sticklebacks Gasterosteus aculeatus, one enclosed in a UV-transmitting (UV+ and another in a UV-blocking (UV- chamber, were simultaneously presented to individual brown trout Salmo trutta. “yearlings”. Brown trout of this age are sensitive to the UV part of the electromagnetic spectrum and are natural predators of three-spined sticklebacks. The stickleback that was attacked first as well as the subsequent number of attacks was recorded. Sticklebacks enclosed in the UV-transmitting chamber were attacked first significantly more often compared to sticklebacks enclosed in the UV-blocking chamber. Control experiments using neutral density filters revealed that this was more likely due to UV having an influence on hue perception rather than brightness discrimination. The difference in attack probability corresponded to the difference in chromatic contrasts between sticklebacks and the experimental background calculated for both the UV+ and UV- conditions in a physiological model of trout colour vision. UV reflections seem to be costly by enhancing the risk of predation due to an increased conspicuousness of prey. This is the first study in a vertebrate, to our knowledge, demonstrating direct predation risk due to UV wavelengths [Current Zoology 59 (2: 151-159, 2013].

  19. Macroparasite communities in European eels, Anguilla anguilla, from French Mediterranean lagoons, with special reference to the invasive species Anguillicola crassus and Pseudodactylogyrus spp.

    Directory of Open Access Journals (Sweden)

    G. Fazio

    2008-01-01

    Full Text Available European eel parasites, in particular invasive species, are suspected to play a role in the decline in the populations of their host. The aims of this work were to describe the parasitic fauna of eels in French Mediterranean lagoons and to study the epidemiological trends of the invasive helminth species, the nematode Anguillicola crassus and the monogenean Pseudodactylogyrus spp., in regard to spatio-temporal dynamics, host biological characteristics and parasite community. A total of 418 eels was sampled in eight lagoons between March 2003 and June 2005. Our results revealed a total macroparasite richness of 23 species: 1 Monogenea, 13 Digenea, 2 Cestoda, 3 Nematoda, 2 Acantocephala and 2 Crustacea. We found no variation in A. crassus abundance in Salses-Leucate lagoon in the same month across years. However, the nematode abundance was higher in eels caught in summer than in those caught in winter. Pseudodactylogyrus sp. was not found in Salses-Leucate lagoon, except in July 2004. Comparisons between the lagoons on the same date showed that they could be separated into two groups for both species' abundance: Grau-du-Roi, Mauguio, Palavas and Vaccarès lagoons, where abundance was rather high, against Bages-Sigean, Pierre-Blanche, Salses-Leucate and Thau lagoons, where abundance was rather low or nil. We found significant negative relationships between A. crassus abundance and the length and age of eels. We also found a significant positive relationship between A. crassus and Pseudodactylogyrus sp. abundance. Finally, our results showed significant positive relationships between both A. crassus and Pseudodactylogyrus sp. abundance and the abundance of the digeneans Prosorhynchus aculeatus and Lecithochirium gravidum. We discuss the results in regard to the dynamics of invasions, the characteristics of the parasite life cycles and the ecology of eels.

  20. Plant Cell Wall Degradation by Saprophytic Bacillus subtilis Strains: Gene Clusters Responsible for Rhamnogalacturonan Depolymerization▿

    Science.gov (United States)

    Ochiai, Akihito; Itoh, Takafumi; Kawamata, Akiko; Hashimoto, Wataru; Murata, Kousaku

    2007-01-01

    Plant cell wall degradation is a premier event when Bacillus subtilis, a typical saprophytic bacterium, invades plants. Here we show the degradation system of rhamnogalacturonan type I (RG-I), a component of pectin from the plant cell wall, in B. subtilis strain 168. Strain 168 cells showed a significant growth on plant cell wall polysaccharides such as pectin, polygalacturonan, and RG-I as a carbon source. DNA microarray analysis indicated that three gene clusters (yesOPQRSTUVWXYZ, ytePQRST, and ybcMOPST-ybdABDE) are inducibly expressed in strain 168 cells grown on RG-I. Cells of an industrially important bacterium, B. subtilis strain natto, fermenting soybeans also express the gene cluster including the yes series during the assimilation of soybean used as a carbon source. Among proteins encoded in the yes cluster, YesW and YesX were found to be novel types of RG lyases releasing disaccharide from RG-I. Genetic and enzymatic properties of YesW and YesX suggest that strain 168 cells secrete YesW, which catalyzes the initial cleavage of the RG-I main chain, and the resultant oligosaccharides are converted to disaccharides through the extracellular exotype YesX reaction. The disaccharide is finally degraded into its constituent monosaccharides through the reaction of intracellular unsaturated galacturonyl hydrolases YesR and YteR. This enzymatic route for RG-I degradation in strain 168 differs significantly from that in plant-pathogenic fungus Aspergillus aculeatus. This is, to our knowledge, the first report on the bacterial system for complete RG-I main chain degradation. PMID:17449691

  1. Plant cell wall degradation by saprophytic Bacillus subtilis strains: gene clusters responsible for rhamnogalacturonan depolymerization.

    Science.gov (United States)

    Ochiai, Akihito; Itoh, Takafumi; Kawamata, Akiko; Hashimoto, Wataru; Murata, Kousaku

    2007-06-01

    Plant cell wall degradation is a premier event when Bacillus subtilis, a typical saprophytic bacterium, invades plants. Here we show the degradation system of rhamnogalacturonan type I (RG-I), a component of pectin from the plant cell wall, in B. subtilis strain 168. Strain 168 cells showed a significant growth on plant cell wall polysaccharides such as pectin, polygalacturonan, and RG-I as a carbon source. DNA microarray analysis indicated that three gene clusters (yesOPQRSTUVWXYZ, ytePQRST, and ybcMOPST-ybdABDE) are inducibly expressed in strain 168 cells grown on RG-I. Cells of an industrially important bacterium, B. subtilis strain natto, fermenting soybeans also express the gene cluster including the yes series during the assimilation of soybean used as a carbon source. Among proteins encoded in the yes cluster, YesW and YesX were found to be novel types of RG lyases releasing disaccharide from RG-I. Genetic and enzymatic properties of YesW and YesX suggest that strain 168 cells secrete YesW, which catalyzes the initial cleavage of the RG-I main chain, and the resultant oligosaccharides are converted to disaccharides through the extracellular exotype YesX reaction. The disaccharide is finally degraded into its constituent monosaccharides through the reaction of intracellular unsaturated galacturonyl hydrolases YesR and YteR. This enzymatic route for RG-I degradation in strain 168 differs significantly from that in plant-pathogenic fungus Aspergillus aculeatus. This is, to our knowledge, the first report on the bacterial system for complete RG-I main chain degradation.

  2. Routine handling methods affect behaviour of three-spined sticklebacks in a novel test of anxiety

    Science.gov (United States)

    Thompson, Ralph R.J.; Paul, Elizabeth S.; Radford, Andrew N.; Purser, Julia; Mendl, Michael

    2016-01-01

    Fish are increasingly popular subjects in behavioural and neurobiological research. It is therefore important that they are housed and handled appropriately to ensure good welfare and reliable scientific findings, and that species-appropriate behavioural tests (e.g. of cognitive/affective states) are developed. Routine handling of captive animals may cause physiological stress responses that lead to anxiety-like states (e.g. increased perception of danger). In fish, these may be particularly pronounced when handling during tank-to-tank transfer involves removal from water into air. Here we develop and use a new combined scototaxis (preference for dark over light areas) and novel-tank-diving test, alongside conventional open-field and novel-object tests, to measure the effects of transferring three-spined sticklebacks (Gasterosteus aculeatus) between tanks using a box or net (in and out of water respectively). Preference tests for dark over light areas confirmed the presence of scototaxis in this species. Open-field and novel-object tests failed to detect any significant differences between net and box-handled fish. However, the combined diving and scototaxis detected consistent differences between the treatments. Net-handled fish spent less time on the dark side of the tank, less time in the bottom third, and kept a greater distance from the ‘safe’ bottom dark area than box-handled fish. Possible explanations for this reduction in anxiety-like behaviour in net-handled fish are discussed. The combined diving and scototaxis test may be a sensitive and taxon-appropriate method for measuring anxiety-like states in fish. PMID:26965568

  3. Review of the Blastobasinae of Costa Rica (Lepidoptera: Gelechioidea: Blastobasidae).

    Science.gov (United States)

    Adamski, David

    2013-02-25

    The Blastobasinae (Lepidoptera: Gelechioidea: Blastobasidae) of Costa Rica are reviewed. Five new genera, Barbaloba, Hallicis, Koleps, Pheos, and Pseudokoleps, and 101 new species are described. They include: Barbaloba jubae, B. meleagrisellae, Hallicis bisetosellus, H. calvicula, Koleps angulatus, Pheos aculeatus, Pseudokoleps akainae, Blastobasis abollae, B. achaea, B. aedes, B. babae, B. balucis, B. beo, B. caetrae, B. chanes, B. custodis, B. dapis, B. deae, B. deliciolarum, B. dicionis, B. echus, B. erae, B. fax, B. furtivus, B. iuanae, B. lex, B. litis, B. lygdi, B. manto, B. neniae, B. nivis, B. orithyia, B. paludis, B. phaedra, B. rotae, B. rotullae, B. tapetae, B. thyone, B. usurae, B. vesta, B. xiphiae, Hypatopa actes, H. acus, H. agnae, H. arxcis, H. bilobata, H. caedis, H. caepae, H. cladis, H. cotis, H. cotytto, H. crux, H. cyane, H. dicax, H. dolo, H. dux, H. edax, H. eos, H. erato, H. fio, H. gena, H. hecate, H. hera, H. hora, H. io, H. ira, H. leda, H. limae, H. lucina, H. joniella, H. juno, H. manus, H. mora, H. musa, H. nex, H. nox, H. phoebe, H. pica, H. plebis, H. rabio, H. rea, H. rego, H. rudis, H. sais, H. scobis, H. semela, H. solea, H. styga, H. texla, H. texo, H. umbra, H. verax, H. vitis, H. vox, Pigritia dido, P. faux, P. gruis, P. haha, P. sedis, P. stips, and P. ululae. Diagnoses, descriptions, and type data are provided for each species. Photographs of imagos, illustrations of wing venation for selected species, male and female genitalia, and distribution maps are furnished. Keys to all genera in Blastobasinae and keys to all species within each genus are provided to assist with identifications. In addition, scanning electron micrographs of the inner surface of the dilated first antennal flagellomere and associated sex scales for all Blastobasis are provided. Blastobasis coffeaella (Busck, 1925), B. graminea Adamski, 1999, Hypatopa tapadulcea Adamski, 1999, and Pigritia marjoriella Adamski, 1998 are redescribed.

  4. Tectonic and regional metamorphic implications of the discovery of Middle Ordovician conodonts in cover rocks east of the Green Mountain massif, Vermont

    Science.gov (United States)

    Ratcliffe, N.M.; Harris, A.G.; Walsh, G.J.

    1999-01-01

    Middle Ordovician (late Arenigian - early Caradocian) conodonts were recovered from a dolostone lens in carbonaceous schist 30 m below the base of the Pinney Hollow Formation in the Eastern Cover sequence near West Bridgewater, Vermont. These are the first reported fossils from the metamorphic cover sequence rocks east of the Green Mountain, Berkshire, and Housatonic massifs of western New England. The conodonts are recrystallized, coated with graphitic matter, thermally altered to a color alteration index (CAI) of at least 5, and tectonically deformed. The faunule is nearly monospecific, consisting of abundant Periodon aculeatus Hadding? and rare Protopanderodus. The preponderance of Periodon and the absence of warm, shallow-water species characteristic of the North American Midcontinent Conodont Province suggest a slope or basin depositional setting. The conodont-bearing carbonaceous schist is traceable 3 km southeast to the Plymouth area, where it had been designated the uppermost member of the Plymouth Formation, previously regarded as Early Cambrian in age. The age and structural position of the carbonaceous schist above dolostones of the Plymouth Formation but below the Pinney Hollow Formation (upper Proterozoic and Lower Cambrian?) suggest that this unit may be correlative or time transgressive with the Ira Formation, which underlies the Taconic allochthons in the Vermont Valley. Such a correlation supports the concept of placing the western limit of the root zone of the Taconic allochthons beneath the Pinney Hollow Formation. An approximate absolute age assignment for the conodont-bearing rock is between 470 and 454 Ma. This suggests that dynamothermal metamorphism during the Taconian orogeny on the east flank of the Green Mountains was younger than early Caradocian, which is in accord with the middle Caradocian age of the Ira Formation west of the Green Mountain massif.

  5. Rates of ingestion and their variability between individual calanoid copepods: Direct observations

    Energy Technology Data Exchange (ETDEWEB)

    Paffenhoefer, G.A.; Lewis, K.D. [Skidaway Inst. of Oceanography, Savannah, GA (United States); Bundy, M.H. [Skidaway Inst. of Oceanography, Savannah, GA (United States)]|[Alfred-Wegener-Institut fuer Polar- und Meeresforschung, Bremerhaven (Germany). Inst. fuer Fernerkundung (IFE); Metz, C. [Alfred-Wegener-Institut fuer Polar- und Meeresforschung, Bremerhaven (Germany). Inst. fuer Fernerkundung (IFE)

    1995-12-01

    The goals of this study were to determine rates of ingestion and fecal pellet release, and their variability, for individual planktonic copepods over extended periods of time (>20 min). Ingestions and rejections of individual cells of the diatom Thalassiosira eccentrica by a adult females of the calanoid Paracalanus aculeatus were directly quantified by observing individual copepods continuously at cell concentrations ranging from 0.1 to 1.2 mm{sup 3} l{sup {minus}1}. Average ingestion rates increased with increasing food concentration, but were not significantly different between 0.3 and 1.0 mm{sup 3} l{sup {minus}1} (9.8 and 32.7 {mu}g Cl{sup {minus}1}) of T.eccentrica. Rates of cell rejections were low and similar at 0.1 and 0.3. but were significantly higher at 1.0 mm{sup 3} l{sup {minus}1}. The coefficients of variation for average ingestion rates of individual copepods hardly differed between food concentrations, ranging from 17 to 22%, and were close to those for average fecal pellet release intervals which ranged from 15 to 21%. A comparison between individuals at each food concentration found no significant differences at 1.0; at 0.1 and 0.3 mm{sup 3} l{sup {minus}1}, respectively, ingestion rates of four out of five females did not differ significantly from each other. Average intervals between fecal pellet releases were similar at 0.3 and 1.0 mm{sup 3} l{sup {minus}1}. Fecal pellet release intervals between individuals were significantly different at each food concentration; these significant differences were attributed to rather narrow ranges of pellet release intervals of each individual female. Potential sources/causes of variability in the sizes and rates of copepods in the ocean are evaluated.

  6. Composition of Fish Communities in a European Macrotidal Salt Marsh (the Mont Saint-Michel Bay, France)

    Science.gov (United States)

    Laffaille, P.; Feunteun, E.; Lefeuvre, J.-C.

    2000-10-01

    At least 100 fish species are known to be present in the intertidal areas (estuaries, mudflats and salt marshes) of Mont Saint-Michel Bay. These and other comparable shallow marine coastal waters, such as estuaries and lagoons, play a nursery role for many fish species. However, in Europe little attention has been paid to the value of tidal salt marshes for fishes. Between March 1996 and April 1999, 120 tides were sampled in a tidal creek. A total of 31 species were caught. This community was largely dominated by mullets ( Liza ramada represent 87% of the total biomass) and sand gobies ( Pomatoschistus minutus and P. lozanoi represent 82% of the total numbers). These species and also Gasterosteus aculeatus , Syngnathus rostellatus, Dicentrarchus labrax, Mugil spp., Liza aurata and Sprattus sprattus were the most frequent species (>50% of monthly frequency of occurrence). In Europe, salt marshes and their creeks are flooded only during high spring tides. So, fishes only invade this environment during short immersion periods, and no species can be considered as marsh resident. But, the salt marsh was colonized by fish every time the tide reached the creek, and during the short time of flood, dominant fishes fed actively and exploited the high productivity. Nevertheless, this study shows that there is little interannual variation in the fish community and there are three ' seasons ' in the fish fauna of the marsh. Marine straggler and marine estuarine dependent species colonize marshes between spring (recruitment period in the bay) and autumn before returning into deeper adjacent waters. Estuarine fishes are present all year round with maximum abundances in the end of summer. The presence of fishes confirms that this kind of wetland plays an important trophic and nursery role for these species. Differences in densities and stages distribution of these species into Mont Saint-Michel systems (tidal mudflats, estuaries and tidal salt marshes) can reduce the trophic

  7. Heritable differences in schooling behavior among threespine stickleback populations revealed by a novel assay.

    Directory of Open Access Journals (Sweden)

    Abigail R Wark

    Full Text Available Identifying the proximate and ultimate mechanisms of social behavior remains a major goal of behavioral biology. In particular, the complex social interactions mediating schooling behavior have long fascinated biologists, leading to theoretical and empirical investigations that have focused on schooling as a group-level phenomenon. However, methods to examine the behavior of individual fish within a school are needed in order to investigate the mechanisms that underlie both the performance and the evolution of schooling behavior. We have developed a technique to quantify the schooling behavior of an individual in standardized but easily manipulated social circumstances. Using our model school assay, we show that threespine sticklebacks (Gasterosteus aculeatus from alternative habitats differ in behavior when tested in identical social circumstances. Not only do marine sticklebacks show increased association with the model school relative to freshwater benthic sticklebacks, they also display a greater degree of parallel swimming with the models. Taken together, these data indicate that marine sticklebacks exhibit a stronger tendency to school than benthic sticklebacks. We demonstrate that these population-level differences in schooling tendency are heritable and are shared by individuals within a population even when they have experienced mixed-population housing conditions. Finally, we begin to explore the stimuli that elicit schooling behavior in these populations. Our data suggest that the difference in schooling tendency between marine and benthic sticklebacks is accompanied by differential preferences for social vs. non-social and moving vs. stationary shelter options. Our study thus provides novel insights into the evolution of schooling behavior, as well as a new experimental approach to investigate the genetic and neural mechanisms that underlie this complex social behavior.

  8. Seasonal activity, vector relationships and genetic analysis of mosquito-borne Stratford virus

    Science.gov (United States)

    Toi, Cheryl S.; Webb, Cameron E.; Haniotis, John; Clancy, John; Doggett, Stephen L.

    2017-01-01

    There are many gaps to be filled in our understanding of mosquito-borne viruses, their relationships with vectors and reservoir hosts, and the environmental drivers of seasonal activity. Stratford virus (STRV) belongs to the genus Flavivirus and has been isolated from mosquitoes and infected humans in Australia but little is known of its vector and reservoir host associations. A total of 43 isolates of STRV from mosquitoes collected in New South Wales between 1995 and 2013 was examined to determine the genetic diversity between virus isolates and their relationship with mosquito species. The virus was isolated from six mosquito species; Aedes aculeatus, Aedes alternans, Aedes notoscriptus, Aedes procax, Aedes vigilax, and Anopheles annulipes. While there were distinct differences in temporal and spatial activity of STRV, with peaks of activity in 2006, 2010 and 2013, a sequence homology of 95.9%–98.4% was found between isolates and the 1961 STRV prototype with 96.2%–100% identified among isolates. Temporal differences but no apparent nucleotide divergence by mosquito species or geographic location was evident. The result suggests the virus is geographically widespread in NSW (albeit only from coastal regions) and increased local STRV activity is likely to be driven by reservoir host factors and local environmental conditions influencing vector abundance. While STRV may not currently be associated with major outbreaks of human disease, with the potential for urbanisation and climate change to increase mosquito-borne disease risks, and the possibility of genomic changes which could produce pathogenic strains, understanding the drivers of STRV activity may assist the development of strategic response to public health risks posed by zoonotic flaviviruses in Australia. PMID:28253306

  9. Conservation of a vitellogenin gene cluster in oviparous vertebrates and identification of its traces in the platypus genome.

    Science.gov (United States)

    Babin, Patrick J

    2008-04-30

    Vitellogenin (Vtg) derivatives are the main egg-yolk proteins in most oviparous animal species, and are, therefore, key players in reproduction and embryo development. Conserved synteny and phylogeny were used to identify a Vtg gene cluster (VGC) that had been evolutionarily conserved in most oviparous vertebrates, encompassing the three linked Vtgs on chicken (Gallus gallus) chromosome 8. Tandem arranged homologs to chicken VtgII and VtgIII were retrieved in similar locations in Xenopus (Xenopus tropicalis) and homologous transcribed inverted genes were found in medaka (Oryzias latipes), stickleback (Gasterosteus aculeatus), pufferfish (Takifugu rubripes), and Tetrahodon (Tetraodon nigroviridis), while zebrafish (Danio rerio) Vtg3 may represent a residual trace of VGC in this genome. Vtgs were not conserved in the paralogous chromosomal segment attributed to a whole-genome duplication event in the ancestor of teleosts, while tandem duplicated forms have survived the recent African clawed frog (Xenopus laevis) tetraploidization. Orthologs to chicken VtgI were found in similar locations in teleost fish, as well as in the platypus (Ornithorhynchus anatinus). Additional Vtg fragments found suggested that VGC had been conserved in this egg-laying mammal. A low ratio of nonsynonymous-to-synonymous substitution values and the paucity of pseudogene features suggest functional platypus Vtg products. Genomic identification of Vtgs, Apob, and Mtp in this genome, together with maximum likelihood and Bayesian inference phylogenetic analyses, support the existence of these three large lipid transfer protein superfamily members at the base of the mammalian lineage. In conclusion, the establishment of a VGC in the vertebrate lineage predates the divergence of ray-finned fish and tetrapods and the shift in reproductive and developmental strategy observed between prototherians and therians may be associated with its loss, as shown by its absence from the genomic resources currently

  10. Maximal release of highly bifidogenic soluble dietary fibers from industrial potato pulp by minimal enzymatic treatment.

    Science.gov (United States)

    Thomassen, Lise V; Vigsnæs, Louise K; Licht, Tine R; Mikkelsen, Jørn D; Meyer, Anne S

    2011-05-01

    Potato pulp is a poorly utilized, high-volume co-processing product resulting from industrial potato starch manufacturing. Potato pulp mainly consists of the tuber plant cell wall material and is particularly rich in pectin, notably galactan branched rhamnogalacturonan I type pectin which has previously been shown to exhibit promising properties as dietary fiber. The objective of this study was to solubilize dietary fibers from potato pulp by a one-step minimal treatment procedure and evaluate the prebiotic potential of the fibers. Statistically designed experiments were conducted to investigate the influence of enzyme type, dosage, substrate level, incubation time, and temperature on the enzyme catalyzed solubilization to define the optimal minimal enzyme treatment for maximal fiber solubilization. The result was a method that within 1 min released 75% [weight/weight (w/w)] dry matter from 1% (w/w) potato pulp treated with 1.0% (w/w) [enzyme/substrate (E/S)] pectin lyase from Aspergillus nidulans and 1.0% (w/w) E/S polygalacturonase from Aspergillus aculeatus at pH 6.0 and 60 °C. Molecular size fractionation of the solubilized fibers revealed two major fractions: one fraction rich in galacturonic acid of 10-100 kDa indicating mainly homogalacturonan, and a fraction >100 kDa rich in galactose, presumably mainly made up of β-1,4-galactan chains of rhamnogalacturonan I. When fermented in vitro by microbial communities derived from fecal samples from three healthy human volunteers, both of the solubilized fiber fractions were more bifidogenic than fructo-oligosaccharides (FOS). Notably the fibers having molecular masses of >100 kDa selectively increased the densities of Bifidobacterium spp. and Lactobacillus spp. 2-3 times more than FOS.

  11. Australian research on ochratoxigenic fungi and ochratoxin A.

    Science.gov (United States)

    Leong, S L; Hocking, A D; Pitt, J I; Kazi, B A; Emmett, R W; Scott, E S

    2006-09-01

    The presence of the mycotoxin, ochratoxin A (OTA), has been reported in Australian grape products. Comprehensive surveys of Australian wines have determined that the frequency and level of OTA contamination are low. Aspergillus carbonarius is the primary OTA-producing species associated with grapes in Australia, and all isolates tested to date produce OTA. Aspergillus niger is isolated more frequently from vineyards, however, few strains produce OTA. A. carbonarius and A. niger exist as saprophytes in the top layer of soil beneath vines, from where they are thought to be blown onto bunches. The level of A. carbonarius in soil may be reduced by temperatures above or below the optimum temperature for survival (25 degrees C), by high soil moisture content, and by modifications to tillage and mulching practices. A. carbonarius is an opportunistic pathogen of damaged berries. In the absence of damage, spores may exist on berry surfaces without causing visible rots. Aspergillus rots are associated with black Aspergillus species, primarily A. niger, A. carbonarius and A. aculeatus. The potential for such rots is increased with berry damage, inoculum coverage and berry maturity. Susceptibility to berry splitting is related, in part, to bunch structure, and may be variety-dependent or influenced by rainfall, irrigation and canopy management. Black Aspergillus spp. are closely associated with berries near the main stem of the bunch. During winemaking, around 80% of the OTA initially present in grapes is removed, primarily with the skins and pulp during pressing. Additional reductions occur with the removal of precipitated grape and yeast solids. Bentonite in white wine and yeast hulls in red wine were the most effective non-carbonaceous fining agents for the removal of OTA.

  12. A revised architecture of primary cell walls based on biomechanical changes induced by substrate-specific endoglucanases.

    Science.gov (United States)

    Park, Yong Bum; Cosgrove, Daniel J

    2012-04-01

    Xyloglucan is widely believed to function as a tether between cellulose microfibrils in the primary cell wall, limiting cell enlargement by restricting the ability of microfibrils to separate laterally. To test the biomechanical predictions of this "tethered network" model, we assessed the ability of cucumber (Cucumis sativus) hypocotyl walls to undergo creep (long-term, irreversible extension) in response to three family-12 endo-β-1,4-glucanases that can specifically hydrolyze xyloglucan, cellulose, or both. Xyloglucan-specific endoglucanase (XEG from Aspergillus aculeatus) failed to induce cell wall creep, whereas an endoglucanase that hydrolyzes both xyloglucan and cellulose (Cel12A from Hypocrea jecorina) induced a high creep rate. A cellulose-specific endoglucanase (CEG from Aspergillus niger) did not cause cell wall creep, either by itself or in combination with XEG. Tests with additional enzymes, including a family-5 endoglucanase, confirmed the conclusion that to cause creep, endoglucanases must cut both xyloglucan and cellulose. Similar results were obtained with measurements of elastic and plastic compliance. Both XEG and Cel12A hydrolyzed xyloglucan in intact walls, but Cel12A could hydrolyze a minor xyloglucan compartment recalcitrant to XEG digestion. Xyloglucan involvement in these enzyme responses was confirmed by experiments with Arabidopsis (Arabidopsis thaliana) hypocotyls, where Cel12A induced creep in wild-type but not in xyloglucan-deficient (xxt1/xxt2) walls. Our results are incompatible with the common depiction of xyloglucan as a load-bearing tether spanning the 20- to 40-nm spacing between cellulose microfibrils, but they do implicate a minor xyloglucan component in wall mechanics. The structurally important xyloglucan may be located in limited regions of tight contact between microfibrils.

  13. Spatial heterogeneity of zooplankton abundance and diversity in the Saudi coastal waters of the Southern Red Sea

    Science.gov (United States)

    Al-Aidaroos, Ali; El-Sherbiny, Mohsen; Mantha, Gopikrishna

    2013-04-01

    The horizontal distribution, abundance and diversity of zooplankton has been studied at 50 stations along the Saudi coastal waters of the southern Red Sea (27 stations around Farasan archipelago, 9 around Al-Qunfodah and 14 around Al-Lith) during March-April 2011 using a plankton net of 150 µm. The zooplankton standing crop fluctuated between 1058 and 25787 individuals/m3 with an average of 5231 individuals/m3. Zooplankton was dominated by holoplanktonic forms that representing 80.26 % of total zooplankton, while meroplanktonic constituting 19.74% and dominated by mollusc larvae. Copepods appeared to be the predominant component, formed an average of 69.69 % of the total zooplankton count followed by chaetognaths and urochordates (4.5 and 4.1% of total zooplankton respectively). A total of 100 copepods species in addition to several species of other planktonic groups (cladocerans, chaetognaths, urochordates) were recorded in the study area. The copepod diversity decreased northward (94, 69 and 62 species at Farasan, Al-Qunfodah and Al-Lith respectively). In general, adult cyclopoid copepods dominated the zooplankton community in term of abundance and species number (19.55 %, 65 species) with dominance of Oncaea media, Oithona similis and Farranula carinata followed by adult calanoid copepods (19.38%, 35 species) with dominance of Paracalanus aculeatus, Clausocalanus minor, Acartia (Acanthacartia) fossae and Centropages orsinii. Harapacticoids densities were low in abundance, represented only by 5 species and dominated mainly by Euterpina acutifronis. Some copepod species decreased northward: Acartia amboinensis, Canthocalanus pauper, Labidocera acuta, Corycaeus flaccus, C. typicus, C. agilis, C. catus, C. giesbrechti, C. latus, C. furcifer and Euterpina acutifronis, while others increased northward (Acartia fossae, Undinula vulgaris and Centropages orsinii). Among copepod orders, Monstrilloida and Siphonostomatoida were observed only in southern area (Farasan

  14. Adaptive genetic variation mediates bottom-up and top-down control in an aquatic ecosystem

    Science.gov (United States)

    Rudman, Seth M.; Rodriguez-Cabal, Mariano A.; Stier, Adrian; Sato, Takuya; Heavyside, Julian; El-Sabaawi, Rana W.; Crutsinger, Gregory M.

    2015-01-01

    Research in eco-evolutionary dynamics and community genetics has demonstrated that variation within a species can have strong impacts on associated communities and ecosystem processes. Yet, these studies have centred around individual focal species and at single trophic levels, ignoring the role of phenotypic variation in multiple taxa within an ecosystem. Given the ubiquitous nature of local adaptation, and thus intraspecific variation, we sought to understand how combinations of intraspecific variation in multiple species within an ecosystem impacts its ecology. Using two species that co-occur and demonstrate adaptation to their natal environments, black cottonwood (Populus trichocarpa) and three-spined stickleback (Gasterosteus aculeatus), we investigated the effects of intraspecific phenotypic variation on both top-down and bottom-up forces using a large-scale aquatic mesocosm experiment. Black cottonwood genotypes exhibit genetic variation in their productivity and consequently their leaf litter subsidies to the aquatic system, which mediates the strength of top-down effects from stickleback on prey abundances. Abundances of four common invertebrate prey species and available phosphorous, the most critically limiting nutrient in freshwater systems, are dictated by the interaction between genetic variation in cottonwood productivity and stickleback morphology. These interactive effects fit with ecological theory on the relationship between productivity and top-down control and are comparable in strength to the effects of predator addition. Our results illustrate that intraspecific variation, which can evolve rapidly, is an under-appreciated driver of community structure and ecosystem function, demonstrating that a multi-trophic perspective is essential to understanding the role of evolution in structuring ecological patterns. PMID:26203004

  15. The impact of selection, gene flow and demographic history on heterogeneous genomic divergence: three-spine sticklebacks in divergent environments.

    Science.gov (United States)

    Ferchaud, Anne-Laure; Hansen, Michael M

    2016-01-01

    Heterogeneous genomic divergence between populations may reflect selection, but should also be seen in conjunction with gene flow and drift, particularly population bottlenecks. Marine and freshwater three-spine stickleback (Gasterosteus aculeatus) populations often exhibit different lateral armour plate morphs. Moreover, strikingly parallel genomic footprints across different marine-freshwater population pairs are interpreted as parallel evolution and gene reuse. Nevertheless, in some geographic regions like the North Sea and Baltic Sea, different patterns are observed. Freshwater populations in coastal regions are often dominated by marine morphs, suggesting that gene flow overwhelms selection, and genomic parallelism may also be less pronounced. We used RAD sequencing for analysing 28 888 SNPs in two marine and seven freshwater populations in Denmark, Europe. Freshwater populations represented a variety of environments: river populations accessible to gene flow from marine sticklebacks and large and small isolated lakes with and without fish predators. Sticklebacks in an accessible river environment showed minimal morphological and genomewide divergence from marine populations, supporting the hypothesis of gene flow overriding selection. Allele frequency spectra suggested bottlenecks in all freshwater populations, and particularly two small lake populations. However, genomic footprints ascribed to selection could nevertheless be identified. No genomic regions were consistent freshwater-marine outliers, and parallelism was much lower than in other comparable studies. Two genomic regions previously described to be under divergent selection in freshwater and marine populations were outliers between different freshwater populations. We ascribe these patterns to stronger environmental heterogeneity among freshwater populations in our study as compared to most other studies, although the demographic history involving bottlenecks should also be considered in the

  16. Treatment of fish parasites. 11. Effects of different benzimidazole derivatives (albendazole, mebendazole, fenbendazole) on Glugea anomala, Moniez, 1887 (Microsporidia): ultrastructural aspects and efficacy studies.

    Science.gov (United States)

    Schmahl, G; Benini, J

    1998-01-01

    Three different benzimidazole derivatives, albendazole [methyl-5-(propylthio)-2-benzimidazolcarbamate], mebendazole (methyl-5-benzoyl-2-benzimidazolcarbamatic acid methyl ester), and fenbendazole [methyl-5-(phenylthio)-2-benzimidazolcarbamate] were tested in vivo against Glugea anomala parasitizing the connective tissue of sticklebacks (Gasterosteus aculeatus). Naturally infected sticklebacks were incubated in aerated plastic aquaria (10 1) at 22 degrees C in water containing 0, 1, 5, 10, or 50 micrograms of either albendazole, mebendazole or febendazole for 2 or 6 h. For intermittent treatment, 2 micrograms substance was administered three times for 6 h at intervals of 36 h. At the ultrastructural level, at all developmental stages of G. anomala there were no significant differences in the kind of damage caused by either albendazole, mebendazole, or febendazole. Starting with a dose of 1 microgram/ml for 2 h, each of the drugs irreversibly damaged uni- and multinucleate meronts, sporogonial plasmodia, and sporoblasts. Disorganized spores were also observed. Treatment with higher doses (10 micrograms/ml, 2 or 6 h) caused malformations of the merogonic and the sporogonic stages, a significant reduction in the number of ribosomes, and disruptions of the nuclear membranes. The first recognizable treatment effect was an enlargement of the smooth endoplasmic reticulum. In the sporogonial plasmodia, the membranes of the sporophorous vesicle envelopes were lumpy or even completely destroyed. After incubation with the highest dose (50 micrograms/ml, 6 h), microtubules were apparent within the karyoplasm of the uninucleate meronts. After interval treatment, all forms of damage were intensified, especially in the mature spores. When treatment was done three times at low doses (3 x 2 micrograms/ml, 6 h, 36-h intervals), spore infectivity was drastically lowered. Therefore, it seems likely that an intermittent regimen of medicinal baths can be successfully applied against

  17. Annual variation of copepod community in the Yangshan Port%洋山港浮游桡足类群落的周年变化特征

    Institute of Scientific and Technical Information of China (English)

    王琼; 陈辰; 吴惠仙; 袁林; 边佳胤; 庄骅; 薛俊增

    2013-01-01

    To understand the annual variation of the copepod community structure, abundance, dominant species and diversity in the Yangshan Port, samples were collected monthly from March 2009 to February 2010. The results showed that the dominant species were Limnoithona tetraspina, Acartia pacifica, Labidocera euchaeta, Paraca-lanus aculeatus, Acartia bifilosa, Microsetella norvegica, Paracalanus gracilis and Paracalanus parvus. The sea-sonal variation in the mean abundance was remarkable(F=2.11, P夏(18.60个/L±14.81个/L)>冬(10.98个/L±3.65个/L)>秋(10.57个/L±4.45个/L);生物量则为夏(12359.1 mg/L±18438.1 mg/L)>秋(7796.6 mg/L±1348.6 mg/L)>冬(2944.8 mg/L±1680.9 mg/L)>春(1401.0 mg/L±1057.3 mg/L).桡足类丰度的周年变化呈现双峰型特征,生物量变化呈现单峰型特征.多变量分析显示,优势种的数量变化对洋山港桡足类群落丰度和生物量的季节变化起主要作用.小洋山码头受人类干扰严重,桡足类丰度和多样性与大洋山码头已出现差异,春、冬季小洋山码头的多样性指数(H′)高于大洋山码头,除秋季外,小洋山码头的均匀度指数(J)都高于大洋山码头.

  18. Expression and evaluation of enzymes required for the hydrolysis of galactomannan.

    Science.gov (United States)

    Malherbe, A R; Rose, S H; Viljoen-Bloom, M; van Zyl, W H

    2014-08-01

    The cost-effective production of bioethanol from lignocellulose requires the complete conversion of plant biomass, which contains up to 30 % mannan. To ensure utilisation of galactomannan during consolidated bioprocessing, heterologous production of mannan-degrading enzymes in fungal hosts was explored. The Aspergillus aculeatus endo-β-mannanase (Man1) and Talaromyces emersonii α-galactosidase (Agal) genes were expressed in Saccharomyces cerevisiae Y294, and the Aspergillus niger β-mannosidase (cMndA) and synthetic Cellvibrio mixtus β-mannosidase (Man5A) genes in A. niger. Maximum enzyme activity for Man1 (374 nkat ml(-1), pH 5.47), Agal (135 nkat ml(-1), pH 2.37), cMndA (12 nkat ml(-1), pH 3.40) and Man5A (8 nkat ml(-1), pH 3.40) was observed between 60 and 70 °C. Co-expression of the Man1 and Agal genes in S. cerevisiae Y294[Agal-Man1] reduced the extracellular activity relative to individual expression of the respective genes. However, the combined action of crude Man1, Agal and Man5A enzyme preparations significantly decreased the viscosity of galactomannan in locust bean gum, confirming hydrolysis thereof. Furthermore, when complemented with exogenous Man5A, S. cerevisiae Y294[Agal-Man1] produced 56 % of the theoretical ethanol yield, corresponding to a 66 % carbohydrate conversion, on 5 g l(-1) mannose and 10 g l(-1) locust bean gum.

  19. The European sea bass Dicentrarchus labrax genome puzzle: comparative BAC-mapping and low coverage shotgun sequencing

    Directory of Open Access Journals (Sweden)

    Volckaert Filip AM

    2010-01-01

    Full Text Available Abstract Background Food supply from the ocean is constrained by the shortage of domesticated and selected fish. Development of genomic models of economically important fishes should assist with the removal of this bottleneck. European sea bass Dicentrarchus labrax L. (Moronidae, Perciformes, Teleostei is one of the most important fishes in European marine aquaculture; growing genomic resources put it on its way to serve as an economic model. Results End sequencing of a sea bass genomic BAC-library enabled the comparative mapping of the sea bass genome using the three-spined stickleback Gasterosteus aculeatus genome as a reference. BAC-end sequences (102,690 were aligned to the stickleback genome. The number of mappable BACs was improved using a two-fold coverage WGS dataset of sea bass resulting in a comparative BAC-map covering 87% of stickleback chromosomes with 588 BAC-contigs. The minimum size of 83 contigs covering 50% of the reference was 1.2 Mbp; the largest BAC-contig comprised 8.86 Mbp. More than 22,000 BAC-clones aligned with both ends to the reference genome. Intra-chromosomal rearrangements between sea bass and stickleback were identified. Size distributions of mapped BACs were used to calculate that the genome of sea bass may be only 1.3 fold larger than the 460 Mbp stickleback genome. Conclusions The BAC map is used for sequencing single BACs or BAC-pools covering defined genomic entities by second generation sequencing technologies. Together with the WGS dataset it initiates a sea bass genome sequencing project. This will allow the quantification of polymorphisms through resequencing, which is important for selecting highly performing domesticated fish.

  20. Genome-Wide DNA Methylation Profiling Reveals Epigenetic Adaptation of Stickleback to Marine and Freshwater Conditions.

    Science.gov (United States)

    Artemov, Artem V; Mugue, Nikolai S; Rastorguev, Sergey M; Zhenilo, Svetlana; Mazur, Alexander M; Tsygankova, Svetlana V; Boulygina, Eugenia S; Kaplun, Daria; Nedoluzhko, Artem V; Medvedeva, Yulia A; Prokhortchouk, Egor B

    2017-09-01

    The three-spined stickleback (Gasterosteus aculeatus) represents a convenient model to study microevolution-adaptation to a freshwater environment. Although genetic adaptations to freshwater environments are well-studied, epigenetic adaptations have attracted little attention. In this work, we investigated the role of DNA methylation in the adaptation of the marine stickleback population to freshwater conditions. DNA methylation profiling was performed in marine and freshwater populations of sticklebacks, as well as in marine sticklebacks placed into a freshwater environment and freshwater sticklebacks placed into seawater. We showed that the DNA methylation profile after placing a marine stickleback into fresh water partially converged to that of a freshwater stickleback. For six genes including ATP4A ion pump and NELL1, believed to be involved in skeletal ossification, we demonstrated similar changes in DNA methylation in both evolutionary and short-term adaptation. This suggested that an immediate epigenetic response to freshwater conditions can be maintained in freshwater population. Interestingly, we observed enhanced epigenetic plasticity in freshwater sticklebacks that may serve as a compensatory regulatory mechanism for the lack of genetic variation in the freshwater population. For the first time, we demonstrated that genes encoding ion channels KCND3, CACNA1FB, and ATP4A were differentially methylated between the marine and the freshwater populations. Other genes encoding ion channels were previously reported to be under selection in freshwater populations. Nevertheless, the genes that harbor genetic and epigenetic changes were not the same, suggesting that epigenetic adaptation is a complementary mechanism to selection of genetic variants favorable for freshwater environment. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. Macroparasite communities in European eels, Anguilla anguilla, from French Mediterranean lagoons, with special reference to the invasive species Anguillicola crassus and Pseudodactylogyrus spp.

    Directory of Open Access Journals (Sweden)

    Fazio G.

    2009-04-01

    Full Text Available European eel parasites, in particular invasive species, are suspected to play a role in the decline in the populations of their host. The aims of this work were to describe the parasitic fauna of eels in French Mediterranean lagoons and to study the epidemiological trends of the invasive helminth species, the nematode Anguillicola crassus and the monogenean Pseudodactylogyrus spp., in regard to spatio-temporal dynamics, host biological characteristics and parasite community. A total of 418 eels was sampled in eight lagoons between March 2003 and June 2005. Our results revealed a total macroparasite richness of 23 species: 1 Monogenea, 13 Digenea, 2 Cestoda, 3 Nematoda, 2 Acantocephala and 2 Crustacea. We found no variation in A. crassus abundance in Salses-Leucate lagoon in the same month across years. However, the nematode abundance was higher in eels caught in summer than in those caught in winter. Pseudodactylogyrus sp. was not found in Salses-Leucate lagoon, except in July 2004. Comparisons between the lagoons on the same date showed that they could be separated into two groups for both species' abundance: Grau-du-Roi, Mauguio, Palavas and Vaccarès lagoons, where abundance was rather high, against Bages-Sigean, Pierre-Blanche, Salses-Leucate and Thau lagoons, where abundance was rather low or nil. We found significant negative relationships between A. crassus abundance and the length and age of eels. We also found a significant positive relationship between A. crassus and Pseudodactylogyrus sp. abundance. Finally, our results showed significant positive relationships between both A. crassus and Pseudodactylogyrus sp. abundance and the abundance of the digeneans Prosorhynchus aculeatus and Lecithochirium gravidum. We discuss the results in regard to the dynamics of invasions, the characteristics of the parasite life cycles and the ecology of eels.

  2. The aggregate site frequency spectrum for comparative population genomic inference.

    Science.gov (United States)

    Xue, Alexander T; Hickerson, Michael J

    2015-12-01

    Understanding how assemblages of species responded to past climate change is a central goal of comparative phylogeography and comparative population genomics, an endeavour that has increasing potential to integrate with community ecology. New sequencing technology now provides the potential to perform complex demographic inference at unprecedented resolution across assemblages of nonmodel species. To this end, we introduce the aggregate site frequency spectrum (aSFS), an expansion of the site frequency spectrum to use single nucleotide polymorphism (SNP) data sets collected from multiple, co-distributed species for assemblage-level demographic inference. We describe how the aSFS is constructed over an arbitrary number of independent population samples and then demonstrate how the aSFS can differentiate various multispecies demographic histories under a wide range of sampling configurations while allowing effective population sizes and expansion magnitudes to vary independently. We subsequently couple the aSFS with a hierarchical approximate Bayesian computation (hABC) framework to estimate degree of temporal synchronicity in expansion times across taxa, including an empirical demonstration with a data set consisting of five populations of the threespine stickleback (Gasterosteus aculeatus). Corroborating what is generally understood about the recent postglacial origins of these populations, the joint aSFS/hABC analysis strongly suggests that the stickleback data are most consistent with synchronous expansion after the Last Glacial Maximum (posterior probability = 0.99). The aSFS will have general application for multilevel statistical frameworks to test models involving assemblages and/or communities, and as large-scale SNP data from nonmodel species become routine, the aSFS expands the potential for powerful next-generation comparative population genomic inference.

  3. Origin, evolution, and biological role of miRNA cluster in DLK-DIO3 genomic region in placental mammals.

    Science.gov (United States)

    Glazov, Evgeny A; McWilliam, Sean; Barris, Wesley C; Dalrymple, Brian P

    2008-05-01

    MicroRNAs (miRNAs) are a rapidly growing family of small regulatory RNAs modulating gene expression in plants and animals. In animals, most of the miRNAs discovered in early studies were found to be evolutionarily conserved across the whole kingdom. More recent studies, however, have identified many miRNAs that are specific to a particular group of organisms or even a single species. These present a question about evolution of the individual miRNAs and their role in establishing and maintaining lineage-specific functions and characteristics. In this study, we describe a detailed analysis of the miRNA cluster (hereafter mir-379/mir-656 cluster) located within the imprinted DLK-DIO3 region on human chromosome 14. We show that orthologous miRNA clusters are present in all sequenced genomes of the placental (eutherian) mammals but not in the marsupial (metatherian), monotreme (prototherian), or any other vertebrate genomes. We provide evidence that the locus encompassing this cluster emerged in an early eutherian ancestor prior to the radiation of modern placental mammals by tandem duplication of the ancient precursor sequence. The original amplified cluster may have contained in excess of 250 miRNA precursor sequences, most of which now appear to be inactive. Examination of the eutherian genomes showed that the cluster has been maintained in evolution for approximately 100 Myr. Analysis of genes that contain predicted evolutionarily conserved targets for miRNAs from this cluster revealed significant overrepresentation of the Gene Ontology terms associated with biological processes such as neurogenesis, embryonic development, transcriptional regulation, and RNA metabolism. Consistent with these findings, a survey of the miRNA expression data within the cluster demonstrates a strong bias toward brain and placenta samples from adult organisms and some embryonic tissues. Our results suggest that emergence of the mir-379/mir-656 miRNA cluster was one of the factors that

  4. Structure and diversity in mammalian accessory olfactory bulb.

    Science.gov (United States)

    Meisami, E; Bhatnagar, K P

    1998-12-15

    The accessory olfactory bulb (AOB) is the first neural integrative center for the olfactory-like vomeronasal sensory system. In this article, we first briefly present an overview of vomeronasal system organization and review the history of the discovery of mammalian AOB. Next, we briefly review the evolution of the vomeronasal system in vertebrates, in particular the reptiles. Following these introductory aspects, the structure of the rodent AOB, as typical of the well-developed mammalian AOB, is presented, detailing laminar organization and cell types as well as aspects of the homology with the main olfactory bulb. Then, the evolutionary origin and diversity of the AOB in mammalian orders and species is discussed, describing structural, phylogenetic, and species-specific variation in the AOB location, shape, and size and morphologic differentiation and development. The AOB is believed to be absent in fishes but present in terrestrial tetrapods including amphibians; among the reptiles AOB is absent in crocodiles, present in turtles, snakes, and some lizards where it may be as large or larger than the main bulb. The AOB is absent in bird and in the aquatic mammals (whales, porpoises, manatees). Among other mammals, AOB is present in the monotremes and marsupials, edentates, and in the majority of the placental mammals like carnivores, herbivores, as well as rodents and lagomorphs. Most bat species do not have an AOB and among those where one is found, it shows marked variation in size and morphologic development. Among insectivores and primates, AOB shows marked variation in occurrence, size, and morphologic development. It is small in shrews and moles, large in hedgehogs and prosimians; AOB continues to persist in New World monkeys but is not found in the adults of the higher primates such as the Old World monkeys, apes, and humans. In many species where AOB is absent in the adult, it often develops in the embryo and fetus but regresses in later stages of

  5. The evolution of milk secretion and its ancient origins.

    Science.gov (United States)

    Oftedal, O T

    2012-03-01

    Lactation represents an important element of the life history strategies of all mammals, whether monotreme, marsupial, or eutherian. Milk originated as a glandular skin secretion in synapsids (the lineage ancestral to mammals), perhaps as early as the Pennsylvanian period, that is, approximately 310 million years ago (mya). Early synapsids laid eggs with parchment-like shells intolerant of desiccation and apparently dependent on glandular skin secretions for moisture. Mammary glands probably evolved from apocrine-like glands that combined multiple modes of secretion and developed in association with hair follicles. Comparative analyses of the evolutionary origin of milk constituents support a scenario in which these secretions evolved into a nutrient-rich milk long before mammals arose. A variety of antimicrobial and secretory constituents were co-opted into novel roles related to nutrition of the young. Secretory calcium-binding phosphoproteins may originally have had a role in calcium delivery to eggs; however, by evolving into large, complex casein micelles, they took on an important role in transport of amino acids, calcium and phosphorus. Several proteins involved in immunity, including an ancestral butyrophilin and xanthine oxidoreductase, were incorporated into a novel membrane-bound lipid droplet (the milk fat globule) that became a primary mode of energy transfer. An ancestral c-lysozyme lost its lytic functions in favor of a role as α-lactalbumin, which modifies a galactosyltransferase to recognize glucose as an acceptor, leading to the synthesis of novel milk sugars, of which free oligosaccharides may have predated free lactose. An ancestral lipocalin and an ancestral whey acidic protein four-disulphide core protein apparently lost their original transport and antimicrobial functions when they became the whey proteins β-lactoglobulin and whey acidic protein, which with α-lactalbumin provide limiting sulfur amino acids to the young. By the late

  6. The mammalian PYHIN gene family: Phylogeny, evolution and expression

    Directory of Open Access Journals (Sweden)

    Cridland Jasmyn A

    2012-08-01

    Full Text Available Abstract Background Proteins of the mammalian PYHIN (IFI200/HIN-200 family are involved in defence against infection through recognition of foreign DNA. The family member absent in melanoma 2 (AIM2 binds cytosolic DNA via its HIN domain and initiates inflammasome formation via its pyrin domain. AIM2 lies within a cluster of related genes, many of which are uncharacterised in mouse. To better understand the evolution, orthology and function of these genes, we have documented the range of PYHIN genes present in representative mammalian species, and undertaken phylogenetic and expression analyses. Results No PYHIN genes are evident in non-mammals or monotremes, with a single member found in each of three marsupial genomes. Placental mammals show variable family expansions, from one gene in cow to four in human and 14 in mouse. A single HIN domain appears to have evolved in the common ancestor of marsupials and placental mammals, and duplicated to give rise to three distinct forms (HIN-A, -B and -C in the placental mammal ancestor. Phylogenetic analyses showed that AIM2 HIN-C and pyrin domains clearly diverge from the rest of the family, and it is the only PYHIN protein with orthology across many species. Interestingly, although AIM2 is important in defence against some bacteria and viruses in mice, AIM2 is a pseudogene in cow, sheep, llama, dolphin, dog and elephant. The other 13 mouse genes have arisen by duplication and rearrangement within the lineage, which has allowed some diversification in expression patterns. Conclusions The role of AIM2 in forming the inflammasome is relatively well understood, but molecular interactions of other PYHIN proteins involved in defence against foreign DNA remain to be defined. The non-AIM2 PYHIN protein sequences are very distinct from AIM2, suggesting they vary in effector mechanism in response to foreign DNA, and may bind different DNA structures. The PYHIN family has highly varied gene composition between

  7. Ecotoxicology of Wild Mammals

    Science.gov (United States)

    2001-01-01

    An international group of 32 scientists has critically reviewed the scientific literature on exposure and effects of environmental contaminants in wild mammals. The underlying theme of this text is encompassed by the following four questions: What exactly do we know about environmental contaminants in mammals? What are the commonalities and differences between mammal orders/species in the effects that contaminants have? How and to what degree of accuracy can we predict the adverse effects of environmental contaminants on mammalian wildlife? How significant are contaminant insults compared with other density-independent and -dependent factors such as habitat loss, climatic factors and disease? The book is organized three topical sections including introductory chapters that provide a background on environmental contaminants and the mammalian orders, eight taxonomic chapters discussing all aspects of the exposure to and effects of contaminants in mammalian orders, and four thematic chapters that review and discuss generic issues including biomarkers, prediction and extrapolation of exposure and effects, hazard and risk assessment, and the relative significance of contaminants on mammals compared with other commonly encountered stressors. A final a summary chapter identifies phylogenetic trends, critical data gaps, and overarching research needs. Although the absolute number of toxicological studies in domesticated and wild mammals eclipses that wildlife species, a detailed examination of our knowledge base reveals that information for 'wild' birds is actually greater than that for 'wild' mammals. Of the various mammalian taxa, ecotoxicological data is most noticeably lacking for marsupials and monotremes. In contrast, rodents (comprising 43% of all mammal species) have been studied extensively, despite evidence of their tolerance to some organochlorine compounds, rodenticides, and even radionuclides. Mammalian species at greatest risk of exposure include those that

  8. Fabrication of anisotropic multifunctional colloidal carriers

    Science.gov (United States)

    Jerri, Huda A.

    The field of colloidal assembly has grown tremendously in recent years, although the direct or template-assisted methods used to fabricate complex colloidal constructions from monodisperse micro- and nanoparticles have been generally demonstrated on model materials. In this work, novel core particle syntheses, particle functionalizations and bottom-up assembly techniques are presented to create functional colloidal devices. Using particle lithography, high-information colloidal vectors have been developed and modified with imaging and targeting agents. Localized nanoscale patches have been reliably positioned on microparticles to serve as foundations for further chemical or physical modifications. Site-specific placement of RGD targeting ligands has been achieved in these lithographed patches. Preferential uptake of these targeted vectors by RGD-specific 3T3 fibroblasts was verified using confocal laser scanning microscopy. A transition was made from the functionalization of model imaging core particles to the lithography of colloidal cartridges, in an effort to construct colloidal syringes with specialized, programmable release profiles. A variety of functional, pH-sensitive fluorescent cores were engineered to respond to solution conditions. When triggered, the diverse composite core microparticles and reservoir microcapsules released embedded fluorescent moieties such as dye molecules, and fluorophore-conjugated nanoparticles. The microcapsules, created using layer-by-layer polyelectrolyte deposition on sacrificial templates, were selectively modified with a robust coating. The pH-responsive anisotropic reservoir microcapsules were extremely stable in solution, and exhibited a "Lazarus" functionality of rehydrating to their original state following desiccation. A snapshot of focused-release of core constituents through the lone opening in colloidal monotremes has been obtained by anisotropically-functionalizing degradable cores with barrier shells. Additionally

  9. Evolution of UCP1 Transcriptional Regulatory Elements Across the Mammalian Phylogeny

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    Michael J. Gaudry

    2017-09-01

    Full Text Available Uncoupling protein 1 (UCP1 permits non-shivering thermogenesis (NST when highly expressed in brown adipose tissue (BAT mitochondria. Exclusive to placental mammals, BAT has commonly been regarded to be advantageous for thermoregulation in hibernators, small-bodied species, and the neonates of larger species. While numerous regulatory control motifs associated with UCP1 transcription have been proposed for murid rodents, it remains unclear whether these are conserved across the eutherian mammal phylogeny and hence essential for UCP1 expression. To address this shortcoming, we conducted a broad comparative survey of putative UCP1 transcriptional regulatory elements in 139 mammals (135 eutherians. We find no evidence for presence of a UCP1 enhancer in monotremes and marsupials, supporting the hypothesis that this control region evolved in a stem eutherian ancestor. We additionally reveal that several putative promoter elements (e.g., CRE-4, CCAAT identified in murid rodents are not conserved among BAT-expressing eutherians, and together with the putative regulatory region (PRR and CpG island do not appear to be crucial for UCP1 expression. The specificity and importance of the upTRE, dnTRE, URE1, CRE-2, RARE-2, NBRE, BRE-1, and BRE-2 enhancer elements first described from rats and mice are moreover uncertain as these motifs differ substantially—but generally remain highly conserved—in other BAT-expressing eutherians. Other UCP1 enhancer motifs (CRE-3, PPRE, and RARE-3 as well as the TATA box are also highly conserved in nearly all eutherian lineages with an intact UCP1. While these transcriptional regulatory motifs are generally also maintained in species where this gene is pseudogenized, the loss or degeneration of key basal promoter (e.g., TATA box and enhancer elements in other UCP1-lacking lineages make it unlikely that the enhancer region is pleiotropic (i.e., co-regulates additional genes. Importantly, differential losses of (or mutations

  10. Multi-metal contamination with uranium trend impact on aquatic environment and consequences for fish immune system and adaptive responses

    Energy Technology Data Exchange (ETDEWEB)

    Le Guernic, A.; Gagnaire, B. [IRSN/PRP-ENV/SERIS/LECO (France); Sanchez, W. [Institut national de l' environnement industriel et des risques - INERIS (France); Betoulle, S. [Champagne Ardenne University (France)

    2014-07-01

    Human activities have conducted to an increase of concentrations of various metals in aquatic ecosystems, including uranium. Its extraction and use have been rapidly magnified because of its role in the nuclear fuel cycle. These activities have led to high concentrations of uranium in the aquatic environment and thus a potential risk to exposed organisms, including fish. Consequences can be observed through metabolic and physiological responses, called biomarkers. Some biomarkers are interesting in order to evaluate the effects of metal contamination, among other immunotoxicity markers, antioxidant defenses and genotoxicity. The aims of this study are: i) to investigate the effects of a multi-metal contamination on a fish, the three-spined stickleback, Gasterosteus aculeatus, and ii) to observe the adaptive capacity of fish due to a combination of stress (chemical stress and biological stress). To meet the first objective, six water bodies (ponds and lakes) located in two departments (Cantal and Haute-Vienne, France) were chosen according to their proximity to old uranium mines and to their levels of metal contamination related to chemical processes appeared during extraction. 240 three-spined sticklebacks were caged for 28 days in the six selected sites. A battery of biomarkers was measured in fish sampled after 14 and 28 of caging. The results for the Haute-Vienne department showed that caged fish in the pond with the highest uranium concentration (20 μg.L{sup -1}) presented the most DNA damage after 14 days of caging. Leukocyte phagocytosis (marker of immunotoxicity) of caged fish in this pond was lower at 14 days and greater at 28 days compared to other ponds without uranium. The multi-metal contamination negatively affected other parameters such as the condition index, oxidative activity, viability of lysosomal membrane and leukocytes distribution. In order to study the response of fish to a combined stress (chemical + biological) (objective ii), a second

  11. Spatial scales of carbon flow in a river food web

    Science.gov (United States)

    Finlay, J.C.; Khandwala, S.; Power, M.E.

    2002-01-01

    Spatial extents of food webs that support stream and river consumers are largely unknown, but such information is essential for basic understanding and management of lotic ecosystems. We used predictable variation in algal ??13C with water velocity, and measurements of consumer ??13C and ??15N to examine carbon flow and trophic structure in food webs of the South Fork Eel River in Northern California. Analyses of ??13C showed that the most abundant macroinvertebrate groups (collector-gatherers and scrapers) relied on algae from local sources within their riffle or shallow pool habitats. In contrast, filter-feeding invertebrates in riffles relied in part on algal production derived from upstream shallow pools. Riffle invertebrate predators also relied in part on consumers of pool-derived algal carbon. One abundant taxon drifting from shallow pools and riffles (baetid mayflies) relied on algal production derived from the habitats from which they dispersed. The trophic linkage from pool algae to riffle invertebrate predators was thus mediated through either predation on pool herbivores dispersing into riffles, or on filter feeders. Algal production in shallow pool habitats dominated the resource base of vertebrate predators in all habitats at the end of the summer. We could not distinguish between the trophic roles of riffle algae and terrestrial detritus, but both carbon sources appeared to play minor roles for vertebrate consumers. In shallow pools, small vertebrates, including three-spined stickleback (Gasterosteus aculeatus), roach (Hesperoleucas symmetricus), and rough-skinned newts (Taricha granulosa), relied on invertebrate prey derived from local pool habitats. During the most productive summer period, growth of all size classes of steelhead and resident rainbow trout (Oncorhynchus mykiss) in all habitats (shallow pools, riffles, and deep unproductive pools) was largely derived from algal production in shallow pools. Preliminary data suggest that the strong

  12. Small Variations in Early-Life Environment Can Affect Coping Behaviour in Response to Foraging Challenge in the Three-Spined Stickleback.

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    M Rohaa Langenhof

    Full Text Available An increasing concern in the face of human expansion throughout natural habitats is whether animal populations can respond adaptively when confronted with challenges like environmental change and novelty. Behavioural flexibility is an important factor in estimating the adaptive potential of both individuals and populations, and predicting the degree to which they can cope with change.This study on the three-spined stickleback (Gasterosteus aculeatus is an empiric illustration of the degree of behavioural variation that can emerge between semi-natural systems within only a single generation. Wild-caught adult sticklebacks (P, N = 400 were randomly distributed in equal densities over 20 standardized semi-natural environments (ponds, and one year later offspring (F1, N = 652 were presented with repeated behavioural assays. Individuals were challenged to reach a food source through a novel transparent obstacle, during which exploration, activity, foraging, sociability and wall-biting behaviours were recorded through video observation. We found that coping responses of individuals from the first generation to this unfamiliar foraging challenge were related to even relatively small, naturally diversified variation in developmental environment. All measured behaviours were correlated with each other. Especially exploration, sociability and wall-biting were found to differ significantly between ponds. These differences could not be explained by stickleback density or the turbidity of the water.Our findings show that a differences in early-life environment appear to affect stickleback feeding behaviour later in life; b this is the case even when the environmental differences are only small, within natural parameters and diversified gradually; and c effects are present despite semi-natural conditions that fluctuate during the year. Therefore, in behaviourally plastic animals like the stickleback, the adaptive response to human-induced habitat disturbance

  13. Feeding ecology of the Stomiiformes (Pisces) of the northern Mid-Atlantic Ridge. 1. The Sternoptychidae and Phosichthyidae

    Science.gov (United States)

    Carmo, Vanda; Sutton, Tracey; Menezes, Gui; Falkenhaug, Tone; Bergstad, Odd Aksel

    2015-01-01

    Comprehensive trophic studies in the vast mid-oceanic regions are rare compared to coastal and fisheries-oriented investigations. Field sampling conducted by the multidisciplinary, international Census of Marine Life project MAR-ECO, namely the 2004 G.O. Sars cruise, has generated one of the largest open ocean deep-pelagic sample collections ever obtained. With the overall goal of understanding carbon flow processes within and through the deep-pelagic nekton associated with the northern Mid-Atlantic Ridge system (N MAR), quantitative trophic analyses were conducted in order to identify the major intraspecific patterns in diet of characteristic members of the midwater fish community. Diets of five abundant species of zooplanktivorous fishes were examined in detail in terms of prey taxonomy and variability in space, ontogeny and diel cycle. Two major patterns of feeding were identified. Pattern 1 included three species preying primarily on copepods, Argyropelecus hemigymnus, Maurolicus muelleri and Vinciguerria attenuata, the former two of which revealed spatial differences in diet with latitude, mostly likely related to latitudinal prey distributions and densities. Maurolicus demonstrated ecological differences in diet that mirrored phenotypic variation North and South of the Subpolar Front, an 'oceanic species concept' question that warrants further research. Pattern 2 included two species feeding primarily on amphipods, Argyropelecus aculeatus and Sternoptyx diaphana, both of which showed ontogenetic variability in feeding primarily related to specific amphipod taxon sizes, rather than prey switching to other major prey taxa. This is the first study that highlights the importance of amphipods in the diets of these species. All fish species showed selectivity in prey choice, possibly related to competition with the other major nekton components along the N MAR, namely the Myctophidae and other zooplanktivorous Stomiiformes. Daily ration fell within the expected

  14. Hepatoprotective herbs, avicenna viewpoint.

    Science.gov (United States)

    Shamsi-Baghbanan, Hamid; Sharifian, Afsaneh; Esmaeili, Somayeh; Minaei, Bagher

    2014-01-01

    Liver injury or dysfunction is considered as a serious health problem. The available synthetic drugs to treat liver disorders are expensive and cause further damage. Hence, hepatoprotective effects of some herbal drugs have been investigated, and one of the methods to choose herbs in order to study their biological effects is to search in ancient medical texts. Avicenna who is known as the prince of physicians had collected and classified Greek, Persian and Islamic medicine in the best possible way in the book of Canon in Arabic. Avicenna's book of The Canon of Medicine was reviewed to find the hepatoprotective herbs. Three different versions of the Canon were prepared and utilized. To find scientific names of plants we took advantage of three botany references. All of the herbs were investigated on the basis of scientific data from hepatoprotective effects point of view. The searched term was "hepatoprotective" without narrowing and limiting. The searched databases included Cochrane library, Web of science, SID, Irandoc and IranMedex. 18 plants were found. 85% of the presented species, genus or families of plants were reported to have hepatoprotective properties and in the remaining 15% there were no reports of hepatoprotective effect. Flowers and fruits were the most used part of the plants. Most of the plants had simultaneous protective effects on multiple organs but the protective effect on the liver was mostly accompanied by protective effect on the stomach (83%). The average temperament of these herbs is "hot" in the 2nd phase of the 2nd grade, and "dry" in the 3rd phase of the 2nd grade. Hepatoprotective herbs mostly prescribed as a part of hepatoprotective compound drugs formula or other formula for liver diseases are Crocus sativus, Pistacia lentiscus, and Cinnamomum spp. Maybe there is common mechanism for protecting both liver and stomach. Aquilaria agallocha, Aquilaria malaccensis, and Ruscus aculeatus whose hepatoprotective effects have not yet been

  15. Screening of the Oleaginous Microorganisms%产油微生物的筛选

    Institute of Scientific and Technical Information of China (English)

    叶思特; 郭丽琼; 刘晓蓉; 陈晓阳; 林俊芳

    2012-01-01

    采用苏丹黑B染色法、甲醇-氯仿法,从30份土壤样品中筛选到9株产油霉菌和4株产油酵母.经5.8S rDNA序列分析,9株产油霉菌分别为蓝状菌Talaromyces trachyspermus、嗜松青霉Penicillium pinophillum、青霉Pe.sp.、微紫青霉Pe.janthinellum、淡紫拟青霉Paecilomyces lilacinus、简青霉Pe.simplicissimum.、棘孢曲霉Aspergillus aculeatus、木霉Trichoderma sp.、拟康宁木霉Tr.koningiopsis,4株产油酵母分别是毕赤酵母Pichia caribbica、假丝孢酵母Candida sp.、季也蒙酵母Meyerozyma guilliermondii和季也蒙毕赤酵母Pi.guilliermondii.通过摇瓶培养,测定了各菌株的产油量,结果表明:霉菌产油量最高的是嗜松青霉,产油量为26.4%;酵母产油量最高的是假丝孢酵母,产油量为44.3%.提取毕赤酵母的油脂,采用气相色谱-质谱联用分析,测得其油脂成分主要是14 ~20碳的短链脂肪酸.%Nine oleaginous moulds and four oleaginous yeasts were isolated from 30 soil samples by using Sudan Black B staining and methanol-chloroform extraction. These oleaginous microorganisms were identified by 5. 8S rDNA sequence analysis. Nine oleaginous moulds were assigned to Talaromyces trachysper-mus, Penicillium pinophillum, Pe. sp. , Pe. janthinellum, Paecilomyces lilacinus, Pe. simplicissimum, As-pergillus aculeatus,Trichoderma sp. and Tr. koningiopsis. Four oleaginous yeasts were Pichia caribbica, Candida sp. , Meyerozyma guilliermondii and Pi. guilliermondii. The lipid yields of the oleaginous microorganisms were tested by cultivation in shake flasks. The highest lipid yield was up to 26.4% by P. pinophillum among 9 oleaginous moulds and 44% by Candida sp. among 4 oleaginous yeasts. The lipid extracted from Candida sp. was mainly composed of 14 -20 short chain fatty acids by GC-MS analysis.

  16. Bet hedging in a warming ocean: predictability of maternal environment shapes offspring size variation in marine sticklebacks.

    Science.gov (United States)

    Shama, Lisa N S

    2015-12-01

    Bet hedging at reproduction is expected to evolve when mothers are exposed to unpredictable cues for future environmental conditions, whereas transgenerational plasticity (TGP) should be favoured when cues reliably predict the environment offspring will experience. Since climate predictions forecast an increase in both temperature and climate variability, both TGP and bet hedging are likely to become important strategies to mediate climate change effects. Here, the potential to produce variably sized offspring in both warming and unpredictable environments was tested by investigating whether stickleback (Gasterosteus aculeatus) mothers adjusted mean offspring size and within-clutch variation in offspring size in response to experimental manipulation of maternal thermal environment and predictability (alternating between ambient and elevated water temperatures). Reproductive output traits of F1 females were influenced by both temperature and environmental predictability. Mothers that developed at ambient temperature (17 °C) produced larger, but fewer eggs than mothers that developed at elevated temperature (21 °C), implying selection for different-sized offspring in different environments. Mothers in unpredictable environments had smaller mean egg sizes and tended to have greater within-female egg size variability, especially at 21 °C, suggesting that mothers may have dynamically modified the variance in offspring size to spread the risk of incorrectly predicting future environmental conditions. Both TGP and diversification influenced F2 offspring body size. F2 offspring reared at 21 °C had larger mean body sizes if their mother developed at 21 °C, but this TGP benefit was not present for offspring of 17 °C mothers reared at 17 °C, indicating that maternal TGP will be highly relevant for ocean warming scenarios in this system. Offspring of variable environment mothers were smaller but more variable in size than offspring from constant environment

  17. Morphology and molecules reveal the alien Posthodiplostomum centrarchi Hoffman, 1958 as the third species of Posthodiplostomum Dubois, 1936 (Digenea: Diplostomidae) in Europe.

    Science.gov (United States)

    Stoyanov, Borislav; Georgieva, Simona; Pankov, Plamen; Kudlai, Olena; Kostadinova, Aneta; Georgiev, Boyko B

    2017-01-01

    Metacercariae of two species of Posthodiplostomum Dubois, 1936 (Digenea: Diplostomidae) were subjected to morphological and molecular studies: P. brevicaudatum (von Nordmann, 1832) from Gasterosteus aculeatus (L.) (Gasterosteiformes: Gasterosteidae), Bulgaria (morphology, cox1 and ITS1-5.8S-ITS2) and Perca fluviatilis L. (Perciformes: Percidae), Czech Republic (morphology, cox1, ITS1-5.8S-ITS2 and 28S); and P. centrarchi Hoffman, 1958 from Lepomis gibbosus (L.) (Perciformes: Centrarchidae), Bulgaria (morphology, cox1 and ITS1-5.8S-ITS2) and Slovakia (cox1 and ITS1-5.8S-ITS2). In addition, cercariae of P. cuticola (von Nordmann, 1832) from Planorbis planorbis (L.) (Mollusca: Planorbidae), Lithuania (morphology and cox1) and metacercariae of Ornithodiplostomum scardinii (Schulman in Dubinin, 1952) from Scardinius erythrophthalmus (L.) (Cypriniformes: Cyprinidae), Czech Republic, were examined (morphology, cox1, ITS1-5.8S-ITS2 and 28S). These represent the first molecular data for species of Posthodiplostomum and Ornithodiplostomum Dubois, 1936 from the Palaearctic. Phylogenetic analyses based on cox1 and ITS1-5.8S-ITS2, using O. scardinii as the outgroup and including the three newly-sequenced Posthodiplostomum spp. from Europe and eight published unidentified (presumably species-level) lineages of Posthodiplostomum from Canada confirmed the distinct status of the three European species (contrary to the generally accepted opinion that only P. brevicaudatum and P. cuticola occur in the Palaearctic). The subspecies Posthodiplostomum minimum centrarchi Hoffmann, 1958, originally described from North America, is elevated to the species level as Posthodiplostomum centrarchi Hoffman, 1958. The undescribed "Posthodiplostomum sp. 3" of Locke et al. (2010) from centrarchid fishes in Canada has identical sequences with the European isolates of P. centrarchi and is recognised as belonging to the same species. The latter parasite, occurring in the alien pumpkinseed sunfish

  18. Exploring Antagonistic Candidate Fungi for Controling Pathogenic Fungi (Colletotricum gloeosporioides Causing Anthracnose Disease in Kintamani Siam Orange Plants (Citrus Nobillis Lour Var. Hass

    Directory of Open Access Journals (Sweden)

    Ni Nyoman Darsini

    2017-02-01

    conventional and molecular identifications, it is known that the two candidate isolates of antagonistic fungus (IS4 and IS7 belong to one species of the Aspergillus aculeatus.

  19. Color signaling in conspicuous red sticklebacks: do ultraviolet signals surpass others?

    Directory of Open Access Journals (Sweden)

    Bakker Theo CM

    2008-07-01

    Full Text Available Abstract Background The use of ultraviolet (UV signals for communication tasks is widespread in vertebrates. For instance, there is a UV component to mate choice in several species. Nevertheless, it remains unclear how the signal value of the UV wave band compares to that of other regions of the animal's visible spectrum. We investigated the relative importance of UV signals compared with signals of longer wavelengths in the threespine stickleback (Gasterosteus aculeatus, a species using UV wavelengths in female and male mate choice as well as in shoaling behavior. In a choice experiment, female sticklebacks were simultaneously presented with four male visual appearances manipulated by optical filters. Each male lacked one wavelength range of the stickleback's visible spectrum corresponding to the spectral sensitivities of the four cone types. The resulting male appearances thus had no UV (UV-, no short-wave (SW-, no medium-wave (MW- or no long-wave (LW- body reflectance. Results Males without UV wavelengths and long wavelengths ("red" were least preferred. In contrast, the removal of medium and most notably short wavelengths left male attractiveness to females rather unaffected. Using color metrics, the effects of the four optical filters on stickleback perception of three male body regions were illustrated as quantal catches calculated for the four single cones. Conclusion The removal of UV light (UV- considerably reduced visual attractiveness of courting males to female three-spined sticklebacks particularly in comparison to the removal of short-wave light (SW-. We thus report first experimental evidence that the UV wave band clearly outranks at least one other part of an animal's visible spectrum (SW- in the context of communication. In addition, females were also less attracted to males presented without long wavelengths (LW- which supports the traditionally considered strong influence of the red color component on stickleback mate choice

  20. Cellulosic ethanol production using a yeast consortium displaying a minicellulosome and β-glucosidase

    Directory of Open Access Journals (Sweden)

    Kim Sujin

    2013-02-01

    Full Text Available Abstract Background Cellulosic biomass is considered as a promising alternative to fossil fuels, but its recalcitrant nature and high cost of cellulase are the major obstacles to utilize this material. Consolidated bioprocessing (CBP, combining cellulase production, saccharification, and fermentation into one step, has been proposed as the most efficient way to reduce the production cost of cellulosic bioethanol. In this study, we developed a cellulolytic yeast consortium for CBP, based on the surface display of cellulosome structure, mimicking the cellulolytic bacterium, Clostridium thermocellum. Results We designed a cellulolytic yeast consortium composed of four different yeast strains capable of either displaying a scaffoldin (mini CipA containing three cohesin domains derived from C. thermocellum, or secreting one of the three types of cellulases, C. thermocellum CelA (endoglucanase containing its own dockerin, Trichoderma reesei CBHII (exoglucanase fused with an exogenous dockerin from C. thermocellum, or Aspergillus aculeatus BGLI (β-glucosidase. The secreted dockerin-containing enzymes, CelA and CBHI, were randomly assembled to the surface-displayed mini CipA via cohesin-dockerin interactions. On the other hand, BGLI was independently assembled to the cell surface since we newly found that it already has a cell adhesion characteristic. We optimized the cellulosome activity and ethanol production by controlling the combination ratio among the four yeast strains. A mixture of cells with the optimized mini CipA:CelA:CBHII:BGLI ratio of 2:3:3:0.53 produced 1.80 g/l ethanol after 94 h, indicating about 20% increase compared with a consortium composed of an equal amount of each cell type (1.48 g/l. Conclusions We produced cellulosic ethanol using a cellulolytic yeast consortium, which is composed of cells displaying mini cellulosomes generated via random assembly of CelA and CBHII to a mini CipA, and cells displaying BGLI independently. One

  1. Duplication of the dystroglycan gene in most branches of teleost fish

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    Giardina Bruno

    2007-05-01

    Full Text Available Abstract Background The dystroglycan (DG complex is a major non-integrin cell adhesion system whose multiple biological roles involve, among others, skeletal muscle stability, embryonic development and synapse maturation. DG is composed of two subunits: α-DG, extracellular and highly glycosylated, and the transmembrane β-DG, linking the cytoskeleton to the surrounding basement membrane in a wide variety of tissues. A single copy of the DG gene (DAG1 has been identified so far in humans and other mammals, encoding for a precursor protein which is post-translationally cleaved to liberate the two DG subunits. Similarly, D. rerio (zebrafish seems to have a single copy of DAG1, whose removal was shown to cause a severe dystrophic phenotype in adult animals, although it is known that during evolution, due to a whole genome duplication (WGD event, many teleost fish acquired multiple copies of several genes (paralogues. Results Data mining of pufferfish (T. nigroviridis and T. rubripes and other teleost fish (O. latipes and G. aculeatus available nucleotide sequences revealed the presence of two functional paralogous DG sequences. RT-PCR analysis proved that both the DG sequences are transcribed in T. nigroviridis. One of the two DG sequences harbours an additional mini-intronic sequence, 137 bp long, interrupting the uncomplicated exon-intron-exon pattern displayed by DAG1 in mammals and D. rerio. A similar scenario emerged also in D. labrax (sea bass, from whose genome we have cloned and sequenced a new DG sequence that also harbours a shorter additional intronic sequence of 116 bp. Western blot analysis confirmed the presence of DG protein products in all the species analysed including two teleost Antarctic species (T. bernacchii and C. hamatus. Conclusion Our evolutionary analysis has shown that the whole-genome duplication event in the Class Actinopterygii (ray-finned fish involved also DAG1. We unravelled new important molecular genetic details

  2. 象山港两种网目网采浮游动物群落比较%A comparison of zooplankton communities collected by two types of nets with different mesh sizes in Xiangshan Bay of Zhejiang, East China

    Institute of Scientific and Technical Information of China (English)

    朱艺峰; 王银; 林霞; 吴燕萍; 赵金龙; 严小军

    2012-01-01

    -3, and 86. 1 mg · m-3 , respectively) were siginificantly lower than those collected by net Ⅱ (84 species, 3780. 2 ind · m-3, and 191. 1 mg · m-3, respectively). In the dominant species, except for Acartia pacifica and Cen-tropages mcmurrichi, the others were completely different between the zooplanktons collected by the two types of nets. In the zooplanktons collected by net type Ⅰ , no species dominating over the year was found, while in the zooplanktons collected by net type Ⅱ , Paracalanus aculeatus and Copepods larva were dominant over the year. The similarity analysis ( ANOSIM) and non-metric multi-dimensional scaling (nMDS) ordination revealed that the community pattern of the zooplanktons collected by the two types of nets had significant spatiotemporal difference, and the community pattern of the zooplanktons collected by net type Ⅰ was more discrete than that of the zooplanktons collected by net type Ⅱ. The analysis of similarity percentage (SIMPER) further revealed that the average dissimilarity of the spatiotemporal difference in the community pattern between the zookplanktons collected by the two types of nets exceeded 75% , and the main discriminating species causing this dissimilarity were Paracalanus aculeatus, Copepods larva, Paracalanus crassirostris, and Oithona brev-icomis, all of which were the dominant species of the zooplanktons collected by net type Ⅱ. In a word, the zooplanktons collected by net type Ⅱ were more representative for the investigation of the zooplanktons in Xiangshan Bay.

  3. Molecular evolution of the polyamine oxidase gene family in Metazoa

    Directory of Open Access Journals (Sweden)

    Polticelli Fabio

    2012-06-01

    monophyletic clades including, respectively, all the SMOs and APAOs from vertebrates. The two vertebrate monophyletic clades clustered strictly mirroring the organismal phylogeny of fishes, amphibians, reptiles, birds, and mammals. Evidences from comparative genomic analysis, structural evolution and functional divergence in a phylogenetic framework across Metazoa suggested an evolutionary scenario where the ancestor PAO coding sequence, present in invertebrates as an orthologous gene, has been duplicated in the vertebrate branch to originate the paralogous SMO and APAO genes. A further genome evolution event concerns the SMO gene of placental, but not marsupial and monotremate, mammals which increased its functional variation following an alternative splicing (AS mechanism. Conclusions In this study the explicit integration in a phylogenomic framework of phylogenetic tree construction, structure prediction, and biochemical function data/prediction, allowed inferring the molecular evolutionary history of the PAO gene family and to disambiguate paralogous genes related by duplication event (SMO and APAO and orthologous genes related by speciation events (PAOs, SMOs/APAOs. Further, while in vertebrates experimental data corroborate SMO and APAO molecular function predictions, in invertebrates the finding of a supported phylogenetic clusters of insect PAOs and the co-occurrence of two PAO variants in the amphioxus urgently claim the need for future structure-function studies.

  4. Checklist of copepods from Gulf of Nicoya, Coronado Bay and Golfo Dulce, Pacific coast of Costa Rica, with comments on their distribution.

    Science.gov (United States)

    Morales-Ramírez, A

    1996-12-01

    also observed, but the separation of the species was not so evident. Outer stations were represented by oceanic species like Paracalanus aculeatus, Pleuromamma gracilis, Lucicutia ovalis, Candacia catula, Euchaeta wolfendeni and Oncaea mediterranea, while the inner station, located at the upper part of the Gulf, was more characterized by a mixed copepod group, with both neritic species like Pseudodiaptomus wrigthi, Acartia danae, A. clausi, Canthocalanus pauper as well as oceanic species like Scolicithricella marginata, Saphirina nicromaculata or Oncaea conifera. Two species of Coryceaus, C. flaccus and C. speciosus, were identified in the outer stations of Golfo Dulce, while C. brehmi was found in inner stations of Gulf of Nicoya. The majority of copepods found are typical of the east Pacific. This paper constitutes an additional work about the copepods in the Gulf of Nicoya and the first report of copepod species for Coronado Bay and Golfo Dulce.

  5. Crims Island-Restoration and monitoring of juvenile salmon rearing habitat in the Columbia River Estuary, Oregon, 2004-10

    Science.gov (United States)

    Haskell, Craig A.; Tiffan, Kenneth F.

    2011-01-01

    -channel' was extended westward and connected to Bradbury Slough to create a second outlet to the main river. New intertidal channels were constructed from the existing 'T-channel' and tidal mudflats became inundated at high tide to increase rearing habitat for juvenile salmonids. The restoration action resulted in a 95-percent increase in available juvenile salmon rearing habitat. We collected juvenile salmon and other fishes at Crims Island and a nearby reference site using beach seines and fyke nets annually from March through August during all years. Benthic invertebrates were collected with sediment corers and drift invertebrates were collected with neuston nets. Juvenile salmon stomach contents were sampled using lavage. Vegetation and sediments characteristics were surveyed and we conducted a topographic/bathymetric survey using a RTK (real time kinematic) GPS (global positioning system). The fish assemblage at Crims Island, composed primarily of threespine stickleback (Gasterosteus aculeatus), non-native banded killifish (Fundulus diaphanus), peamouth chub (Mylocheilus caurinus), subyearling Chinook salmon (Oncorhynchus tshawytscha) (hereinafter referred to as subyearlings), and small numbers of juvenile chum salmon (Oncorhynchus keta), did not differ appreciably pre- and post-restoration. Subyearlings were the primary salmonid collected and were seasonally abundant from April through May during all years. The abundance of juvenile salmon declined seasonally as water temperature exceeded 20 degrees C in the Reference site by mid-June; however, subyearlings persisted at the Mainstem site and in subtidal channels of the Restoration site through the summer in water temperatures exceeding 22 degrees C. Residence times of subyearlings in Crims Island backwaters generally were short consisting of one or two tidal cycles. Median residence time was longer in the Restoration site than in the Reference site pre- and post-restoration. Small (mean = 55.7 millimeters) subyea

  6. Review of the Spirobolida on Madagascar, with descriptions of twelve new genera, including three genera of 'fire millipedes' (Diplopoda

    Directory of Open Access Journals (Sweden)

    Thomas Wesener

    2009-09-01

    Full Text Available Twelve new genera and 37 new species of Spirobolida are described: Corallobolus cruentus gen. n., sp. n., Sanguinobolus maculosus gen. n., sp. n., Colossobolus semicyclus gen. n., sp. n., C. oblongopedus sp. n., C. giganteus sp. n., C. minor sp. n., C. litoralis sp. n., C. aculeatus sp. n., C. pseudoaculeatus sp. n., Zehntnerobolus gen. n., Flagellobolus pauliani gen. n., sp. n., Riotintobolus mandenensis gen. n., sp. n., R. minutus sp. n., R. aridus sp. n., R. anomalus sp. n., Pseudocentrobolus aureus gen. n., sp. n., P. vohibasiensis sp. n., Granitobolus endemicus gen. n., sp. n., G. andohahelensis sp. n., Caprobolus andringitra gen. n., sp. n., Alluviobolus laticlavius gen. n., sp. n., A. tsimelahy sp. n., A. antanosy sp. n., Ostinobolus rufus gen. n., sp. n., O. stellaris sp. n., O. montanus sp. n., O. subterraneus sp. n., and Hylekobolus brachiosauroides gen. n., sp. n., H. rufus sp. n., H. griseus sp. n., H. albicollaris sp. n., H. goodmani sp. n., H. montanus sp. n., H. analavelona sp. n., H. latifrons sp. n., H. andasibensis sp. n., H. marojejy sp. n., H. anjanaharibe sp. n. All genera and species are endemic to Madagascar. Hylekobolus belongs to the family Spirobolellidae, while all other Malagasy genera of Spirobolida belong to the Pachybolidae. Among them, only Zehntnerobolus gen. n. is based on a previously described species: Spirobolus rubripes de Saussure & Zehntner, 1897, whereas the remaining 11 new genera altogether contain (a total of 37 new species. Three of the new genera are large-bodied “fire millipedes” (>100 mm long with striking red/black colour patterns. The new discoveries increase the number of endemic Malagasy genera of Spirobolida more than fivefold (from 3 to 15. The number of endemic species recorded from Madagascar has more than doubled (to 61. Body length of the new species varies greatly (between 23 and 170 mm. Keys to all Malagasy Spirobolida families, genera, as well as the newly described species

  7. 多基因联合分析棒束孢属Isaria (Ascomycota,Cordycipitaceae)系统发育关系%Multilocus phylogenetic analyses of the genus Isaria (Ascomycota, Cordycipitaceae)

    Institute of Scientific and Technical Information of China (English)

    代永东; 虞泓; 曾文波; 杨俊媛; 何璐

    2016-01-01

    对棒束孢属Isaria及近缘属物种开展5基因(nrSSU、nrLSU、tef-1α、rpb1和rpb2)测序并联合分析,结合GenBank相关类群序列,探讨棒束孢属系统发育关系,最终获得95个菌株、58个明确分类群的2-5基因序列.利用MEGA和MrBayes软件进行多基因聚类分析,结果表明棒束孢属多系起源于虫草菌科中,分3个不同分支.A支主要由Isaria cicadae、I.teniupes、I.coleopterorum、I.fumosorosea和I.cateniannulata等组成;B支包括I.poprawki、I.Iocustica、I.javanica、I.amoenerosea和I.cateniobliqua;C支仅有I.farinosa.分支间被Cordyceps militaris、C.ninchukispora、C.pruinosa等隔开.棒束孢在形态上,主要以瓶梗基部膨大、尖端变细及孢子呈链状等特征与其他类群分开,但同时也发现有棒状分生孢子梗和单孢子类型.基于节点的分歧时间预测分析,推测棒束孢属首次分化于70Mya,但棒束孢属主要物种形成却在60-55Mya,且3个分支的棒束孢物种为快速同时形成,而后大多数类群表现遗传稳定.同时发现,与Isaria Clade A较近一支有粉被玛利亚霉Mariannaea pruinosa(C.pruinosa无性型)和蛹草蚧霉Lecanicillium militaris(C.militaris无性型);与粉棒束孢距离最近一支有Akanthomyces aculeatus(C.tuberculata无性型)和L.attenuatum(C.confragosa无性型),是两个不同的属征分类群,且相互间遗传距离较近.根据棒束孢属及其近缘种属形态特征的复杂性推测,棒束孢属在快速物种形成中,其近缘类群存在一定程度的丢失和选择性演化.

  8. Paleobiogeografía y paleoecología de los mamíferos continentales de América del Sur durante el Cretácico tardío-Paleoceno: una revisión

    Directory of Open Access Journals (Sweden)

    Ortiz Jaureguizar, E.

    1996-04-01

    Full Text Available The purpose of this paper is to outline the most recent advances in the knowledge of paleobiogeography and paleoecology of the South American continental mammals during the late Cretaceous-Paleocene span. Two basic parameters were considered: (1 taxonomic richness; and (2 trophic diversity. The genera recorded in the four «land-mammal Ages» (SALMAs that represent the late Cretaceous-Paleocene span, i.e., Alamitian (late Cretaceous, Tiupampian (early Paleocene, Itaboraian (middle Paleocene, and Riochican (late Paleocene, were used as analytical units. As conclusion, is possible to point out that: 1 During the Alamitian SALMA the faunistic composition of South America was markedly different of that of the holarctic continents, due to the exclusive presence of pre-tribosphenic taxa of pangeic jurassic ancestry, although mostly showing a marked degree of endemism. 2 The tiupampian fauna was basically characterized by the absence of most of the alamitian pre-tribosphenic groups (except the gondwanatherian «multituberculates» and by the presence of a «mix» of taxa with narrow relationships with North America (e.g., pantodonts in association with other proper of South America but with holarctic (e.g., marsupial s or eastern gondwanic ancestry (i.e., monotremes. 3 The most marked compositional change in the South American mammal fauna was recorded between the Alamitian and Tiupampian SALMAs. 4 Beginning to the Itaboraian SALMA, the South American mammal fauna newly shows a marked endemic character that will distinguish all the continental mammal faunas throughout the rest of the Cenozoico 5 The absence of xenarthrans in the pre-itaboraian mammal- bearing sediments is particularly surprising. 6 The diversity of trophic types increases from Alamitian to Riochican SALMAs, because of the progressive occupation of the empty adaptive zones after the dinosaurs extinction, and the opening of new ones. 7 The «cast- of the trophic types

  9. Cloning and bioinformatics analysis of aromatization gene P450c17 in sea cucumber Apostichopus japonicus (Selenka)%仿刺参性别相关基因P450c17的克隆与序列分析

    Institute of Scientific and Technical Information of China (English)

    田燚; 张丙龙; 常亚青

    2012-01-01

    .%本研究克隆了仿刺参(Apostichopus japonicus)P450c17基因的全长cDNA,结果表明其cDNA的5′端UTR为256 bp,3′端UTR为250 bp,ORF为l 530 bp.在3′端有特殊序列ATTTA、终止密码子TAA和polyA加尾.其全长cDNA编码509个氨基酸的前体蛋白,预测蛋白分子量57.6 kD,理论等电点5.5.P450c17的氨基酸序列存在长度为25个氨基酸的信号肽,1个长度为22个氨基酸的跨膜区,1个糖基结合位点NHS,1个P450特有的结构域,其氨基酸序列具有明显的细胞色素P450基因家族的特征.结构域中亚铁血红素结合域中的精氨酸R和发挥活性所必须的半胱氨酸C都是保守的.这些结构组成了血红素结合环、质子传递槽和K螺旋及绝对保守EXXR基序.蛋白前体二级结构中无规则卷曲占41.22%,延伸链占12.77%,α-螺旋占46.01%,不含B-折叠.氨基酸序列与其他物种氨基酸序列的同源性在35%~41%之间.系统进化树表明仿刺参与长牡蛎(Crassostrea gigas)及文昌鱼(Branchiostoma belcheri)聚为一支,黄颡鱼(Pelteobagrus fulvidraco)、鲇(Clarias gariepinus)、日本鳗鲡(Anguilla japonica)及白斑角鲨(Squalus acanthias)聚为一支,三刺鱼(Gasterosteus aculeatus)、金眼门齿鲷(Stenotomus chrysops)、斑马鱼(Danio rerio)、鲤(Cyprinus carpio)、虹鳟(Oncorhynchus mykiss)、牙鲆及青鳉(Fundulus heteroclitus) 聚为一支.研究结果为进一步探讨仿刺参P450c17在性激素调控性别分化方面的功能提供参考.

  10. 广东省恩平市锦江河上游野生鱼类资源群落生态特征调查%A preliminary study on the structure of wild fish community in the upstream of Jinjiang River

    Institute of Scientific and Technical Information of China (English)

    谭乾开; 黎华寿; 崔科; 贺鸿志

    2012-01-01

    2009年6月至9月连续16次对广东省恩平市锦江河上游主要鱼类群落调查。调查共捕获鱼类3 894尾隶属6目18科39属49种。其中未知种3种,Margalef指数D(I)为4.023 9,D(B)为7.601 4,Shannon-Wiener指数H(I′)为3.952 3,H(B′)为2.401 9;Simpson指数C(I)为0.705 1,C(B)为0.914 3;Pielou指数J(I)为0.331 3,J(B)为0.201 4。其中名特优经济鱼类15种,占种类数的30.61%,包括刺鳅、黄颡鱼、月鳢、胡子鲶、翘嘴红鱼白、黄鳝、鲶鱼、乌鳢、翘嘴鳜、斑鳜、加洲鲈、泥鳅等普通经济鱼类8种,占种类数的16.32%,包括鲫鱼、罗非鱼、银鲴、鲤、草鱼、鲢、鳙、青鱼、鲮等;其他非经济鱼类种26种,不知品种3种,占种类数的53.06%。鲤形目中的鲤、银飘鱼为优势种(IRI≥500),鲫、、寡鳞飘鱼、赤眼鳟、油餐、彩石等为常见种;鲈形目中的罗非鱼属鱼类、子陵吻虾虎鱼为优势种(IRI≥500),月鳢、乌鳢、加洲鲈、斗鱼、溪吻虾虎鱼、粘皮鲻虾虎鱼、侧扁黄(鱼幼)等为常见种;鱼将形目中的食蚊鱼和鲶形目的胡子鲶为优势种(IRI≥500),合鳃目的黄鳝以及外来种观赏鱼(吸盘鱼)、鲶鱼为常见种,鱼类品种调查结果可为恩平市锦江河鱼类资源保护和利用提供参考。%We carried 16 surveys of the wild fish community in the upstream of Jinjiang River in Enping from June to September, 2009. The 3 894 fish we captured belong to 49 species, 39 genus, 18 familia, 6 order, including 3 unknown species. The indexes of Margalef D(1) and D(B), Shannon- WienerH(1) and H(B), Simpson C(1) and C(B), and Pielou J(1) and J(B) are 4.023 9 and 7. 601 4, 3.952 3 and 2. 401 9, 0. 705 1 and 0. 914 3 and 0. 331 3 and 0. 201 4 respectively. 15 species including Mastacembelus aculeatus, Pelteobagrus fulvidraco, Channa asiatica, Clarias batrachus, Culter alburnus , Symbranchi formes Monopterusalba