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1.
Abstract. Pamexis Hagen, 1866, is revised. Myrmeleon luteum Thunberg is designated as type species. A key is provided for the five species comprising the genus. Pamexis luteus (Thunberg, 1784), P.bifasciatus (Olivier, 1811) and P.contaminatus (Hagen, 1887) are redescribed: P.karoo and P.namaqua are new species. All are endemic to the Cape Province of South Africa.  相似文献   

2.
GGA triplet repeats are widely dispersed throughout eukaryotic genomes and are frequently located within biologically important regions such as gene regulatory regions and recombination hot spot sites. We determined the structure of d(GGA)4 (12-mer) under physiological conditions and founded the formation of an intramolecular parallel quadruplex for the first time. Later, a similar architecture to that of the intramolecular parallel quadruplex was found for a telomere DNA in the crystalline state. Here, we have determined the structure of d(GGA)8 (24-mer) under physiological conditions. Two intramolecular parallel quadruplexes comprising a G:G:G:G tetrad and a G(:A):G(:A):G(:A):G heptad are formed in d(GGA)8. These quadruplexes are packed in a tail-to-tail manner. This is the first demonstration of the intramolecular higher order packing of quadruplexes at atomic resolution. K+ ions, but not Na+ ones, are critically required for the formation of this unique structure. The elucidated structure suggests the mechanisms underlying the biological events related to the GGA triplet repeat. Furthermore, in the light of the structure, the mode of the higher order packing of the telomere DNA is discussed.  相似文献   

3.
Several morphological forms (morphotypes) of Urospora chiridotae gamontes are found in White Sea holothuroid Chiridota laevis. All these morphotypes are differed by localization in the body of host, form and cytological features. The gregarines are situated in several host biotopes, such as blood vessels, intestine and mesenteries. In the blood vessels elongate skittle-like cells supplied with long thin cytopillia are observed. On the external surface of the intestine spherical gregarines are found. These parasites commonly covered with one layer of coelomic epithelium's cells. In some holothuria intratissue spherical cells of parasites located in intestinal epithelium are presented. Both of these types of parasites lack cytopillia, and folds or ridges on its surface. On different mesenteries, connections between intestine and body wall, and also on intestine elongate ounce-shaped cells and gamontocysts are observed. These cells are situated on the apices of finger-like processes of the intestine and mesenteries surface. Ounce-shaped gregarines have cytopillia shorter than in skittle-like gregarines. The differences between morphotypes of Urospora chiridotae are probably caused by different environmental conditions. In the narrow rift of blood vessel elongate cells are developed. The cytopillia may serve for making more or less wide space around gregarines, which is necessary for food uptake. Spherical cells surrounded by host's cells and have the form typical for tissue parasites. In the wide coelomic cavity where convection of liquid proceeds better than in blood vessel, ounce-shaped gregarines with short cytopillia are developed. We found only typical for Urospora chiridotae ovoid oocysts with dissimilar ends, anterior collar and spine-like posterior end. Thus, the all above-mentioned morphotypes undoubtedly belong to the same species. The relationships between defense host cells and the different morphotypes of trophozoites are variable.  相似文献   

4.
The putative pea PINOID homolog, PsPK2, is expressed in all growing plant parts and is positively regulated by auxin, gibberellin, and cytokinin. Here, we studied hormonal regulation of PsPK2::GUS expression compared with DR5::GUS and PID::GUS in Arabidopsis. PsPK2::GUS, DR5::GUS, and PID::GUS expression in Arabidopsis shoots is mainly localized in the stipules, hydathodes, veins, developing leaves, and cotyledons. Unlike DR5::GUS, PsPK2::GUS, and PID::GUS are weakly expressed in root tips. Both DR5::GUS and PsPK2::GUS are induced by different auxins and are more sensitive to methyl indole acetic acid, 4-chloro-indole acetic acid, and α-naphthalene acetic acid than others. GA(3) has no significant effect on GUS activity in DR5::GUS-transformed seedlings compared to the control, but induction by auxin and gibberellin in combination is synergistic. Cytokinin increases auxin transport in Arabidopsis seedlings. Auxin, gibberellin, and cytokinin all increase GUS activity in shoots of PsPK2::GUS transformed plants compared to the control. However, only auxin and gibberellin increase GUS activity in PID::GUS shoots. In conclusion, auxin, gibberellin, and cytokinin positively regulate PsPK2 expression in shoots, but not in roots. Auxin and gibberellin also upregulate AtPIN1 and LEAFY expression, which is similar to PsPIN1 and Uni in pea. With minor exceptions, the orthologous genes from both species are regulated similarly.  相似文献   

5.
The modern and native distributions of wax scales are documented and an area cladogram including seventy species is presented. Wax scales are distributed worldwide, but most species are native to either South America or Africa. Their native distribution pattern is discussed in relation to their host-plant specificity and to the dispersal and vicariance theories of biogeography. The vicariance theory is preferred, because the pattern can be explained satisfactorily by plate tectonics but not by dispersal from a centre of origin. The wax scale group probably originated in the combined South American–African continent at least 97 million yr ago.  相似文献   

6.
Abstract. The genus Microdonacia Blackburn is revised and its systematic position considered. Ten species are treated, seven of which are new ( bidentata, eucryphiae, grevitteae, incurva, octodentata, pilosa, pomaderris ), and lectotypes are designated for two species. Four of the new species are placed in Tantawangalo subgen.n. Microdonacia is compared with the genera Cassena Weise, Licyllus Jacoby and Orthaltica Crotch. The sister-group for Microdonacia is identified as Orthaltica and these genera are placed incertae sedis in the Galerucinae, as used in the sense of Crowson (1967). The proposed phylogeny of the species is illustrated on a cladogram.  相似文献   

7.
Cytological events immediately following plasmogamy in Durvillaea potatorum are described. Eggs contain several types of cytoplasmic vesicle differing in size and appearance. Histochemical tests and measurements are used to characterise and distinguish different types of vesicle containing phenolic compounds, lipids and polysaccharides. Within 2 min of plasmogamy, small phenolic vesicles located just below the egg membrane undergo mass synchronised exocytosis. The contents of these vesicles are discharged as phenolic bodies on the outside of the membrane. Secretion of phenolic bodies precedes secretion of the primary zygote wall by several minutes. Limited secretion of phenolics also occurs in unfertilised eggs. Peripheral phenolic vesicles are distinguishable from physodes, which also contain phenolic compounds but which are significantly larger and tend to be localised around the egg nucleus. The possible functional significance of the phenolic bodies is discussed. Coated pits and vesicles are common in zygotes, and their presence is evidence for endocytosis.  相似文献   

8.
Thermoluminesence measurements are useful for the study of Photosystem II electron transport in intact leaves, in algal and cyanobacterial cells, as well as in isolated membrane complexes. Here an overview of the experimental approaches is provided. In the present review, instruments and the experimental procedures for measuring thermoluminescence emission from photosynthetic systems of various origins are summarized and discussed. Major pitfalls frequently encountered in measurements with isolated membranes, suspensions of intact organisms or solid leaf samples are highlighted. Analytical and numeric methods for the analysis of measured thermoluminescence curves are also discussed.  相似文献   

9.
The genus Hemibidessus Zimmermann, 1921 is revised. Six species are recognized in the genus. Two new species are described, H. spirodiscus sp. n. from Bolivia and H. spangleri sp. n. from Argentina. A key for identifying the species is presented. The female genitalia are thoroughly illustrated and described for the first time for any species of Bidessini. Other important diagnostic structures are also illustrated including the male genitalia. A cladistic analysis is presented for 8 species (6 ingroup and 2 outgroup species) and 13 characters. A single most parsimonious cladogram was found.  相似文献   

10.
11.
Orchid bees (Euglossini) are spectacular long-tongued Neotropical bees important in the pollination of Neotropical long-corolla flowers, particularly some orchids. Besides remarkably long tongues, males in particular exhibit other flower-related adaptations, including setal brushes on the foretarsi used for rasping the petals of orchids while collecting aromatic compounds. These compounds are stored in large swollen tibiae and are thought to play an important role in courtship behavior. Euglossini are also unusual in lacking sociality; they are the only tribe among the corbiculate bees that are not eusocial, and two of the genera are cleptoparasitic. Each genus exhibits distinct behavioral traits including nest architecture and host-parasite interactions, yet their evolution is unknown. Despite previous phylogenetic studies of on morphological characters, the relationships among the five euglossine genera remain under debate. We investigate euglossine generic relationships using DNA sequence data from four genes and new morphological characters. The morphological and molecular data yield congruent evolutionary patterns, and combining the data gives a fully resolved and well supported phylogeny of Euglossini.  相似文献   

12.
The anomuran crabs are among the best known crustacean groups from the Pacific coast. However, this group is poorly known from the Caribbean coast of Costa Rica. In this compilation based on the literature and the collection at the Zoology Museum, Biology School, University of Costa Rica, we report the presence of 114 species of the Infraorder Anomura for Costa Rica, 20 species from the Caribbean, 96 species from the Pacific (two are present on both coasts). Twenty-nine species are new reports for Costa Rica, 15 from the Caribbean coast (74% of the total of species from that coast) and 14 from the Pacific (15% of the total from the Pacific). The range often species is extended to Costa Rica, siete from the Caribbean and three from the Pacific. Six species are reported for the first time from Cocos Island, where there are also four endemic species.  相似文献   

13.
The false spider crabs of the family Hymenosomatidae are one of the most poorly known group of brachyuran crabs in Southeast Asia. This is largely attributed to their small size and cryptic behaviour. Despite the many studies of decapods in Southeast Asia, only eleven species of hymenosomatids are known. Of these, two genera and six species were only described in the last two years. From Singapore the largest number of species (five) has been reported probably because it has been the best explored, while from Thailand three species and Peninsular Malaysia two species are known. There are no published records of hymenosomatids from Borneo or Java. The hymenosomatid fauna is perhaps best known in Australia and New Zealand. It is anticipated that when proper collections are made and studies implemented, the Southeast Asian hymenosomatid fauna will prove to be more diverse than what has been reported. The ecology of the Southeast Asian species is reviewed, especially in the view that two species are completely freshwater, one of which is a troglobite. Most species are littoral or sublittoral in habit and very sensitive to human activities (e.g. pollution).  相似文献   

14.
The jumping plant-lice or psyllids belonging to the subfamily Liviinae are reviewed. Nineteen species are recognized in a single genus Lima Latreille. Three new species, craivfordi sp. nov., lobata sp. nov. and manitobensis sp. nov., are described. The identities of the existing species have been widely confused and full lists of synonymies are given where appropriate. It is re-emphasized that the type species of Livia, Psylla juncorum Latreille, is a synonym of Chermes junci Schrank, a point made by Laing (1951) but ignored by subsequent authors. The latter name has priority. A taxonomic key for the identification of the species is given and each species is described, diagnosed and illustrated. Supporting information is given on geographical distribution, host-plant association and general biology. Evolutionary relationships within Livia are discussed.  相似文献   

15.
Sedatives are widely prescribed for anxiety or insomnia and include benzodiazepines, selective benzodiazepine receptor subtype agonists (z-drugs), and barbiturates. These sedatives are controlled substances due to their potential for misuse and abuse. Misuse is often self-medication (chemical coping) of psychological symptoms in ways unauthorized by the prescriber, usually as dose escalation leading to requests for early refills. Sedatives are abused for euphoric effects, which may have dangerous consequences. Some sedative overdoses can be treated with flumazenil, a reversal agent, along with supportive care. Sedative withdrawal syndrome is treated by tapering the sedative and may require hospitalization. Long-term treatment of sedative addiction requires counseling, often with the help of an addiction-treatment professional.  相似文献   

16.
The phylogeny of the large genus Bembidion and related genera is inferred from four nuclear protein-coding genes (CAD, wingless, arginine kinase, and topoisomerase I), ribosomal DNA (28S and 18S), and the mitochondrial gene cytochrome oxidase I (COI). 230 of the more than 1200 species of Bembidion are sampled, as well as 26 species of five related genera, and 14 outgroups. Nuclear copies (numts) of COI were found sparsely scattered through sampled species. The resulting phylogeny, based upon individual gene analyses and combined analyses using maximum likelihood and parsimony, is very well supported at most nodes. Additional analyses explored the evidence, and corroborate the phylogeny. Seven analyses, each with one of the seven genes removed from the combined matrix, were also conducted, and yielded maximum likelihood bootstrap trees sharing over 92% of their nodes with the original, well-resolved bootstrap trees based on the complete set of seven genes. All key nodes were present in all seven analyses missing a single gene, indicating that support for these nodes comes from at least two genes. In addition, the inferred maximum likelihood tree based on the combined matrix is well-behaved and self-predicting, in that simulated evolution of sequences on the inferred tree under the inferred model of evolution yields a matrix from which all but one of the model tree's clades are recovered with bootstrap value >50, suggesting that internal branches in the tree may be of a length to yield sequences sufficient to allow their inference. All likelihood analyses were conducted under both a proportion-invariable plus gamma site-to-site rate variation model, as well as a simpler gamma model. The choice of model did not have a major effect on inferred phylogenies or their bootstrap values. The inferred phylogeny shows that Bembidarenas is not closely related to Bembidiina, and Phrypeus is likely distant as well; the remaining genera of Bembidiina form a monophyletic group. Lionepha, formerly considered a subgenus of Bembidion, is shown to be outside of the clade of Asaphidion+Bembidion, and is separated as its own genus. B. (Phyla) obtusum is quite isolated within Bembidion, and there is some evidence that the remaining Bembidion form a clade. Within Bembidion, there are three large clades that are well-supported, the Bembidion, Odontium, and Ocydromus Series. The Bembidion Series contains Bembidion (s. str.), Notaphus, Furcacampa, Emphanes, Trepanedoris, Diplocampa, and related Holarctic species; all species from South America, Australia, New Zealand; and most species from southern Africa and Madagascar. All species in South America, except for members of Notaphus and Nothocys, form a clade, the Antiperyphanes Complex, which has independently radiated into body forms and niches occupied by multiple, independent Northern-Hemisphere forms. All species from New Zealand, including Zecillenus, and Australian species formerly placed in Ananotaphus together form a clade. Bembidion (s. str.) and Cyclolopha are in a clade with the Old World, Southern Hemisphere lineages Notaphocampa, Sloanephila, and Omotaphus. The large subgenus Notaphus appears to have originated in South America, with all Northern Hemisphere Notaphus arising from within a south-temperate grade. All major variation in frontal furrows on the head is contained within the Bembidion Series. The Odontium Series contains subgenera Hirmoplataphus and Hydriomicrus, which together are the sister clade of Odontium, Bracteon, Ochthedromus, Pseudoperyphus, and Microserrullula. The very large Ocydromus Series, dominant in the Holarctic region, includes the Ocydromus Complex, with many subgenera, including Hypsipezum and Leuchydrium; the phylogeny within this group is notably at odds with the current classification. Also included in the Ocydromus Series are Nepha and Bembidionetolitzkya, as well as the Princidium Complex, in which the intertidal B. (Cillenus) laterale falls. Outside these three series are a number of smaller groups, including the Plataphus Complex (containing Blepharoplataphus, Plataphus, the latter including Plataphodes); the Hydrium Complex (Metallina, Chlorodium, and Hydrium, which contains Eurytrachelus), whose sister group might be subgenus Andrewesa; Trechonepha and Liocosmius, which might be sisters; and B. (Melomalus) planatum, which is not close to Plataphus. There is some evidence that these groups plus the Ocydromus and Odontium Series form a clade. A few enigmatic groups were harder to place. The sister group of the pair Philochthus plus Philochthemphanes might be B. wickhami; Eupetedromus is well outside the three major series and not related to Notaphus; the high-elevation Asian group Hoquedela is a very isolated lineage. Notaphiellus is removed from synonymy with Nothocys, and placed in synonymy with Notaphus; Plataphodes is synonymized with Plataphus, as Plataphus is paraphyletic otherwise; Eurytrachelus is synonymized with Hydrium. A new subgenus, Lindrochthus, is described to house the distinctive B. wickhami. The implications of the inferred phylogeny for some morphological characters used in Bembidiina systematics are explored, and some of the most widely used (e.g., location of discal seta ed3 on the elytron, and shape of the shoulder) are shown to be notably homoplastic. For example, the location of elytral seta ed3 has undergone at least nine transitions between two states.  相似文献   

17.
Innovation: Metabolomics: the apogee of the omics trilogy   总被引:3,自引:0,他引:3  
Metabolites, the chemical entities that are transformed during metabolism, provide a functional readout of cellular biochemistry. With emerging technologies in mass spectrometry, thousands of metabolites can now be quantitatively measured from minimal amounts of biological material, which has thereby enabled systems-level analyses. By performing global metabolite profiling, also known as untargeted metabolomics, new discoveries linking cellular pathways to biological mechanism are being revealed and are shaping our understanding of cell biology, physiology and medicine.  相似文献   

18.

Background  

The true water bugs are grouped in infraorder Nepomorpha (Insecta: Hemiptera: Heteroptera) and are of great economic importance. The phylogenetic relationships within Nepomorpha and the taxonomic hierarchies of Pleoidea and Aphelocheiroidea are uncertain. Most of the previous studies were based on morphological characters without algorithmic assessment. In the latest study, the molecular markers employed in phylogenetic analyses were partial sequences of 16S rDNA and 18S rDNA with a total length about 1 kb. Up to now, no mitochondrial genome of the true water bugs has been sequenced, which is one of the largest data sets that could be compared across animal taxa. In this study we analyzed the unresolved problems in Nepomorpha using evidence from mitochondrial genomes.  相似文献   

19.
The Japanese species of the genus Agraphydrus are revised. Five species are recognized, including Agraphydrus ogatai sp. nov. from Honshu, Shikoku and Kyushu. The new species can be distinguished by the coarse ground punctures on the pronotum and elytra, and by the shape of parameres. All species except A. luteilateralis are redescribed. All species are diagnosed, relevant morphological characters are illustrated, distributional records are summarized and an updated key is provided.  相似文献   

20.
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