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1.
We isolated 11 polymorphic microsatellites from blue coral (Heliopora coerulea), whose conservation and management are of great concern. The number of alleles ranged from 3 to 20 with an average of 5.5, and the observed and expected heterozygosities ranged from 0.115 to 0.833 and from 0.371 to 0.915, respectively. These loci are useful for conservation genetics in H. coerulea populations.  相似文献   

2.
The maT clade of transposons is a group of transposable elements intermediate in sequence and predicted protein structure to mariner and Tc transposons, with a distribution thus far limited to a few invertebrate species. We present evidence, based on searches of publicly available databases, that the nematode Caenorhabditis briggsae has several maT-like transposons, which we have designated as CbmaT elements, dispersed throughout its genome. We also describe two additional transposon sequences that probably share their evolutionary history with the CbmaT transposons. One resembles a fold back variant of a CbmaT element, with long (380-bp) inverted terminal repeats (ITRs) that show a high degree (71%) of identity to CbmaT1. The other, which shares only the 26-bp ITR sequences with one of the CbmaT variants, is present in eight nearly identical copies, but does not have a transposase gene and may therefore be cross mobilised by a CbmaT transposase. Using PCR-based mobility assays, we show that CbmaT1 transposons are capable of excising from the C. briggsae genome. CbmaT1 excised approximately 500 times less frequently than Tcb1 in the reference strain AF16, but both CbmaT1 and Tcb1 excised at extremely high frequencies in the HK105 strain. The HK105 strain also exhibited a high frequency of spontaneous induction of unc-22 mutants, suggesting that it may be a mutator strain of C. briggsae.  相似文献   

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We examined the diurnal refuges occupied by the nocturnal squirrelfish, Holocentrus rufus, to describe refuges and the behavior associated with their use and to determine which, if any, refuge characteristics were selected. We tagged 21 H. rufus on two sites on a fringing reef in Barbados, West Indies, identified the refuges they used (n = 57), measured ten characteristics of each refuge and the surrounding microhabitat, and monitored their refuge use for 4 weeks. To evaluate refuge selection, we measured the same characteristics on a comparable number of unused potential refuges (n = 67) on the same reefs and used classification tree models to determine which characteristics separated used from unused refuges. Each fish used 1–9 refuges, which did not overlap among individuals and were defended against intrusion by conspecifics and some heterospecifics. Fish with more than one refuge frequently moved among them. There was strong site fidelity with no immigration of untagged fish or emigration of tagged fish on either reef during the study period and no additional refuges being occupied over the 4-week period. Refuges were primarily holes, open at one or two ends, which varied in size, distance from the reef edge, entrance orientation, and vertical relief at the entrance. Holes used as refuges differed significantly from unused holes mainly in characteristics related to the vertical position of their entrance, but the classification tree models differed for the two sites. This study provides the first detailed information on characteristics of daytime refuges used by a nocturnally active reef fish and the first evidence of selectivity of refuges. It suggests that the abundance and characteristics of holes on reefs could influence the density of H. rufus on natural reefs.  相似文献   

5.
P transposons belong to the eukaryotic DNA transposons, which are transposed by a cut and paste mechanism using a P-element-coded transposase. They have been detected in Drosophila, and reside as single copies and stable homologous sequences in many vertebrate species. We present the P elements Pcin1, Pcin2 and Pcin3 from Ciona intestinalis, a species of the most primitive chordates, and compare them with those from Ciona savignyi. They showed typical DNA transposon structures, namely terminal inverted repeats and target site duplications. The coding region of Pcin1 consisted of 13 small exons that could be translated into a P-transposon-homologous protein. C. intestinalis and C. savignyi displayed nearly the same phenotype. However, their P elements were highly divergent and the assumed P transposase from C. intestinalis was more closely related to the transposase from Drosophila melanogaster than to the transposase of C. savignyi. The present study showed that P elements with typical features of transposable DNA elements may be found already at the base of the chordate lineage. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

6.
Summary   Funastrum rupicola Goyder, a new species of Apocynaceae: Asclepiadoideae from Bolivia, is described and illustrated. The conservation status of this species is assessed.  相似文献   

7.
We have investigated the floral ontogeny of Arillastrum, Allosyncarpia, Stockwellia and Eucalyptopsis (of the eucalypt group, Myrtaceae) using scanning electron microscopy and light microscopy. Several critical characters for establishing relationships between these genera and to the eucalypts have been determined. The absence of compound petaline primordia in Arillastrum, Allosyncarpia, Stockwellia and Eucalyptopsis excludes these taxa from the eucalypt clade. Post-anthesis circumscissile abscission of the hypanthium above the ovary in Stockwellia, Eucalyptopsis and Allosyncarpia is evidence that these three taxa form a monophyletic group; undifferentiated perianth parts and elongated fusiform buds are characters that unite Stockwellia and Eucalyptopsis as sister taxa. No floral characters clearly associate Arillastrum with either the eucalypt clade or the clade of Stockwellia, Eucalyptopsis and Allosyncarpia.We gratefully acknowledge Clyde Dunlop and Bob Harwood (Northern Territory Herbarium) for collecting specimens of Allosyncarpia, and Bruce Gray (Atherton) for collecting specimens of Stockwellia. The Australian National Herbarium (CANB) kindly lent herbarium specimens of Eucalyptopsis for examination. This research was supported by a University of Melbourne Research Development Grant to Andrew Drinnan.  相似文献   

8.
Seol E  Jung Y  Lee J  Cho C  Kim T  Rhee Y  Lee S 《Plant cell reports》2008,27(7):1197-1206
Notocactus scopa cv. Soonjung was subjected to in planta Agrobacterium tumefaciens-mediated transformation with vacuum infiltration, pin-pricking, and a combination of the two methods. The pin-pricking combined with vacuum infiltration (20-30 cmHg for 15 min) resulted in a transformation efficiency of 67-100%, and the expression of the uidA and nptII genes was detected in transformed cactus. The established in planta transformation technique generated a transgenic cactus with higher transformation efficiency, shortened selection process, and stable gene expression via asexual reproduction. All of the results showed that the in planta transformation method utilized in the current study provided an efficient and time-saving procedure for the delivery of genes into the cactus genome, and that this technique can be applied to other asexually reproducing succulent plant species.  相似文献   

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A pea rust fungus, Uromyces viciae-fabae, has been classified into two varieties, var. viciae-fabae and var. orobi, based on differences in urediniospore wall thickness and putative host specificity in Japan. In principal component analyses, morphological features of urediniospores and teliospores of 94 rust specimens from Vicia, Lathyrus, and Pisum did not show definite host-specific morphological groups. In molecular analyses, 23 Uromyces specimens from Vicia, Lathyrus, and Pisum formed a single genetic clade based on D1/D2 and ITS regions. Four isolates of U. viciae-fabae from V. cracca and V. unijuga could infect and sporulate on P. sativum. These results suggest that U. viciae-fabae populations on different host plants are not biologically differentiated into groups that can be recognized as varieties.Contribution no. 184, Laboratory of Plant Parasitic Mycology, Institute of Agriculture and Forestry, University of Tsukuba, Japan  相似文献   

13.
Genome sequence analysis of Xanthomonas oryzae pv. oryzae has revealed a cluster of 12 ORFs that are closely related to the gum gene cluster of Xanthomonas campestris pv. campestris. The gum gene cluster of X. oryzae encodes proteins involved in xanthan production; however, there is little experimental evidence supporting this. In this study, biochemical analyses of xanthan produced by a defined set of X. oryzae gum mutant strains allowed us to preliminarily assign functions to most of the gum gene products: biosynthesis of the pentasaccharide repeating unit for GumD, GumM, GumH, GumK, and GumI, xanthan polymerization and transport for GumB, GumC, GumE, and GumJ, and modification of the pentasaccharide repeating unit for GumF, GumG, and GumL. In addition, we found that the exopolysaccharides are essential but not specific for the virulence of X. oryzae. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Sang-Yoon Kim and Jeong-Gu Kim contributed equally to this work.  相似文献   

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Summary  A new monotypic bamboo genus Phuphanochloa (Poaceae: Bambusoideae) from north-eastern Thailand is described, together with a new species, P. speciosa.  相似文献   

15.
We isolated the full-length cDNAs of engrailed and dpp-BMP2/4 orthologues from the pond snail Lymnaea stagnalis and examined their expression patterns during development by the whole mount in situ hybridization. At the gastrula and trochophore stages, engrailed is expressed in the peripheral ectoderm of the presumptive and invaginating shell gland, corroborating its role in the shell formation that is widely conserved among molluscs. At the same stages, dpp-BMP2/4 is expressed in the right-hand side ectoderm of the shell gland and in the invaginating stomodaeum. Unlike in the gastropod Patella vulgata, our results suggested that dpp-BMP2/4 has a role in the shell formation, rather than in the regional specification and that it could be involved in the specification pathway of the left–right asymmetry of the developing shell in L. stagnalis.  相似文献   

16.
Butterflies of the highly endangered genus Maculinea are parasites of red Myrmica ants. Prior to the adoption by Myrmica worker ants Maculinea caterpillars feed on a specific host plant. This field study aims to answer the question whether the density and distribution of the host plant Sanguisorba officinalis or the density of the host ant M. rubra limit the density of M. nausithous egg, larval and adult stage. We found that the density of M. nausithous egg stage and adult stage increased with the density of the host ant. The density of M. nausithous caterpillars was not associated with ant density or plant density. This study suggests that the density of M. nausithous is limited by the density of the host ant M. rubra. We conclude that habitat management for M. nausithous should focus on the maintenance of habitats that hold both resources, but that enable high densities of M. rubra. In addition, it is discussed why high densities of host ants might be more important in predatory than in cuckoo-feeding Maculinea.  相似文献   

17.
Carotenoids represent a group of valuable molecules for the pharmaceutical, chemical, food and feed industries, not only because they can act as vitamin A precursors, but also for their coloring, antioxidant and possible tumor-inhibiting activity. Animals cannot synthesize carotenoids, and these pigments must therefore be added to the feeds of farmed species. The synthesis of different natural commercially important carotenoids (β-carotene, torulene, torularhodin and astaxanthin) by several yeast species belonging to the genera Rhodotorula and Phaffia has led to consider these microorganisms as a potential pigment sources. In this review, we discuss the biosynthesis, factors affecting carotenogenesis in Rhodotorula and Phaffia strains, strategies for improving the production properties of the strains and directions for potential utility of carotenoid-synthesizing yeast as a alternative source of natural carotenoid pigments.  相似文献   

18.
A cDNA coding for the C-terminus of spider flagelliform silk protein (AvFlag) was cloned from Araneus ventricosus. Analysis of the cDNA sequence shows that the C-terminus of AvFlag consists of 167 amino acids of a repetitive region and 87 amino acids of a C-terminal non-repetitive region. The peptide motifs found in spider flagelliform silk proteins, GPGGX and GGX, were conserved in the repetitive region of AvFlag. Phylogenetic analysis further confirmed that AvFlag belongs to the spider flagelliform silk proteins. The AvFlag cDNA was expressed as a 28 kDa polypeptide in baculovirus-infected insect cells. As a new expression approach for spider silk protein, the combination of polyhedrin and AvFlag creates a polyhedrin AvFlag fusion protein (61 kDa) that is produced as recombinant polyhedra; this provides a basis for the source of spider silk proteins for various applications.  相似文献   

19.
Environmental manipulation or conservation is one among several approaches evolved for harnessing the potentiality of entomopathogens in an integrated pest management. Cultural manipulation can permit the pathogen to reproduce more than usual or can preserve or enhance those already present. Among the key pest of chilli thrips, Scirtothrips dorsalis Hood (Thripidae: Thysanoptera) and broad mite, Polyphagotarsonemus latus [Banks] (Tarsonemoidea: Acari) are reported to cause the leaf curl in the leaves of chilli. Fusarium semitectum has infected the thrips and mites. The effectiveness of the mycopathogen, F. semitectum is chiefly influenced by the environmental conditions. Enhancing the microclimate the mycopathogen can be able to develop and buildup further. Chilli has been grown as sole crop, however companion crops such as sorghum, cotton, red gram, castor and maize were grown to understand the cropping system effect. Chilli-sorghum, chilli-cotton-chilli and chilli-red gram were the best cropping systems in terms of total chilli yield. The chilli-cotton-chilli cropping system ranked second with respect to benefit-cost ratio of 1:1 where as chilli-sorghum cropping system claimed the highest as 1.125:1. Interestingly, sorghum is not grown as a companion crop with chilli in Karnataka under rain fed conditions, where as chilli-cotton combination is a practice in many places of the state.  相似文献   

20.
A Sebacinales species was recovered from a clone library made from a pooled rhizosphere sample of Nicotiana attenuata plants from 14 native populations. Axenic cultures of the related species, Piriformospora indica and Sebacina vermifera, were used to examine their effects on plant performance. Inoculation of N. attenuata seeds with either fungus species stimulated seed germination and increased growth and stalk elongation. S. vermifera inoculated plants flowered earlier, produced more flowers and matured more seed capsules than did non-inoculated plants. Jasmonate treatment during rosette-stage growth, which slows growth and elicits herbivore resistance traits, erased differences in vegetative, but not reproductive performance resulting from S. vermifera inoculation. Total nitrogen and phosphorous contents did not differ between inoculated and control plants, suggesting that the performance benefits of fungal inoculation did not result from improvements in nutritional status. Since the expression of trypsin proteinase inhibitors (TPI), defensive proteins which confer resistance to attack from Manduca sexta larvae, incur significant growth and fitness costs for the plant, we examined the effect of S. vermifera inoculation on herbivore resistance and TPI activity. After 10 days of feeding on S. vermifera-inoculated plants, larval mass was 46% higher and TPI activity was 48% lower than that on non-inoculated plants. These results suggest that Sebacina spp. may interfere with defense signaling and allow plants to increase growth rates at the expense of herbivore resistance mediated by TPIs.  相似文献   

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