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1.
Juvenile hormone (JH) signaling underpins both regulatory and developmental pathways in insects. However, the JH receptor is poorly understood. Methoprene tolerant (Met) and germ cell expressed (gce) have been implicated in JH signaling in Drosophila. We investigated the evolution of Met and gce across 12 Drosophila species and found that these paralogs are conserved across at least 63 million years of dipteran evolution. Distinct patterns of selection found using estimates of dN/dS ratios across Drosophila Met and gce coding sequences, along with their incongruent temporal expression profiles in embryonic Drosophila melanogaster, illustrate avenues through which these genes have diverged within the Diptera. Additionally, we demonstrate that the annotated gene CG15032 is the 5′ terminus of gce.In mosquitoes and beetles, a single Met-like homolog displays structural similarity to both Met and gce, and the intron locations are conserved with those of gce. We found that Tribolium and mosquito Met orthologs are assembled from Met- and gce-specific domains in a modular fashion. Our results suggest that Drosophila Met and gce experienced divergent evolutionary pressures following the duplication of an ancestral gce-like gene found in less derived holometabolous insects.  相似文献   

2.
The continued development of effective anti-tick vaccines remains the most promising prospect for the control of the cattle tick, Rhipicephalus (Boophilus) microplus. A vaccine based on midgut proteins could interfere with successful tick feeding and additionally interfere with midgut developmental stages of Babesia parasites, providing opportunities for the control of both the tick and the pathogens it transmits. Midgut proteins from partially fed adult female cattle ticks were analysed using a combination of 2-DE and gel-free LC-MS/MS. Analysis of the urea-soluble protein fraction resulted in the confident identification of 105 gut proteins, while the PBS-soluble fraction yielded an additional 37 R. microplus proteins. The results show an abundance of proteins involved in mitochondrial ATP synthesis, electron transport chain, protein synthesis, chaperone, antioxidant and protein folding and transport activities in midgut tissues of adult female ticks. Among the novel products identified were clathrin-adaptor protein, which is involved in the assembly of clathrin-coated vesicles, and membrane-associated trafficking proteins such as syntaxin 6 and surfeit 4. The observations allow the formulation of hypotheses regarding midgut physiology and will serve as a basis for future vaccine development and tick-host interaction research.  相似文献   

3.
Torrubiella is a genus of arthropod-pathogenic fungi that primarily attacks spiders and scale insects. Based on the morphology of the perithecia, asci, and ascospores, it is classified in Clavicipitaceae s. lat. (Hypocreales), and is considered a close relative of Cordyceps s. 1., which was recently reclassified into three families (Clavicipitaceae s. str., Cordycipitaceae, Ophiocordycipitaceae) and four genera (Cordyceps s. str, Elaphocordyceps, Metacordyceps, and Ophiocordyceps). Torrubiella is distinguished morphologically from Cordyceps s. lat. mainly by the production of superficial perithecia and the absence of a well-developed stipitate stroma. To test and refine evolutionary hypotheses regarding the placement of Torrubiella and its relationship to Cordyceps s. lat., a multi-gene phylogeny was constructed by conducting ML and Bayesian analyses. The monophyly of Torrubiella was rejected by these analyses with species of the genus present in Clavicipitaceae, Cordycipitaceae, and Ophiocordycipitaceae, and often intermixed among species of Cordyceps s. lat. The morphological characters traditionally used to define the genus are, therefore, not phylogenetically informative, with the stipitate stromata being gained and/or lost several times among clavicipitaceous fungi. Two new genera (Conoideocrella, Orbiocrella) are proposed to accommodate two separate lineages of torrubielloid fungi in the Clavicipitaceae s. str. In addition, one species is reclassified in Cordyceps s. str. and three are reclassified in Ophiocordyceps. The phylogenetic importance of anamorphic genera, host affiliation, and stipitate stromata is discussed.  相似文献   

4.
5.
In the temporary carboniferous hall of „GONDWANA - Das Prähistorium“ in Germany, whip spiders (Damon variegatus) were kept and bred. 3,3 were purchased from a dealer in summer 2007. The night active spiders were kept together in a terrarium. No aggresions were observed. The animals were fed little locusts, young hissing cockroaches, and crickets. In 2008 courtship display and mating could be observed. The biggest male was the only active one. After 7 days after the intake of the spermatophores all females carried eggsacs under the ophistosoma. Each egg sack contained approximately 25-30 eggs. During the carrying phase only one female feasted on a cricket. 98 days after the egg sack was produced the young spiderlings hatched. The coloration of the spiderlings was completely different from the coloration of the adults. The spiderlings were carried by the female for the next 9 days. Then, the spiderlings moulted and left the female immediately. The adults were now separated from their young. The three groups of spiderlings stayed together in a smaller terrarium. However, each group from each female stayed separate from the others for weeks. The second moulting took place 41 days after the first one. No cannibalism was observed. Obviously Damon variegatus seems to be a spider with a social touch. If the terrarium and the climate conditions inside are adapted to the needs of the whip spiders keeping and breeding is possible. The species is highly attractive to visitors.  相似文献   

6.
Khalil G. M., Hoogstraal H. and Oliver J. H. Jr. 1980. Biological evaluation of the systematic validity of the African Argas (Persicargas) arboreus and the Asian-Australian A.(P.)robertsi (Ixodoidea: Argasidae). International journal for Parasitology10: 253–259. The closely related A. (P.)arboreus (Ethiopian Faunal Region) and A. (P.) robertsi (Oriental and Australian Faunal Regions) interbreed readily and produce partially fertile progeny. Intrahybrid crosses are much less productive than P1 homogamic crosses. Results of backcrosses indicate that the progeny of the robertsi ♂ × arboreus ♀ cross are less fertile than the progeny of the reciprocal cross. The fertility of F1 hybrid progeny is lower than that of the P1 pure species as expressed in lower female fecundity, egg hatch, and/or viability of immature stages. These 2 species probably originated from a common ancestor and geographic isolation caused genetic incompatibility.  相似文献   

7.
This study reconstructs early stages of Rozella allomycis endoparasitic infection of its host, Allomyces macrogynus. Young thalli of A. macrogynus were inoculated with suspensions of R. allomycis zoospores and allowed to develop for 120 h. Infected thalli at intervals were fixed for electron microscopy and observed. Zoospores were attracted to host thalli, encysted on their surfaces, and penetrated their walls with an infection tube. The parasite cyst discharged its protoplast through an infection tube, which invaginated the host plasma membrane. The host plasma membrane then surrounded the parasite protoplast and formed a compartment confining it inside host cytoplasm. The earliest host-parasite interface within host cytoplasm consisted of two membranes, the outer layer the host plasma membrane and the inner layer the parasite plasma membrane. At first a wide space separated the two membranes and no material was observed within this space. Later, as the endoparasite thallus expanded within the compartment, the two membranes became closely appressed. As the endoparasite thallus continued to enlarge, the interface developed into three membrane layers. Thus, host plasma membrane surrounded the parasite protoplast initially without the parasite having to pierce the host plasma membrane for entry. Significantly, host-derived membrane was at the interface throughout development.  相似文献   

8.
The morphology and ultrastructure of the male reproductive system of dwarfish males of the monoecious aphid species Glyphina betulae (subfamily Thelaxinae) and the heteroecious species Anoecia (Anoecia) corni (subfamily Anoeciinae) are described. The testicular follicle of these species has the form of a single sac, the proximal parts of the vasa deferentia are slightly (G. betulae) or strongly (A. (A.) corni) expanded, the accessory glands are sack-shaped, and in G. betulae asymmetric and strongly elongated, whereas the ejaculatory duct is short.In both species only mature spermatozoa have been found within the testicular follicles, i.e. the consecutive stages of spermatogenesis have not been observed in adult males. Our studies also show that the testicular follicle, vasa deferentia, accessory glands and ejaculatory duct are histologically very simple. They are composed of more-or-less flattened epithelium of a secretory type, and thin muscle fibres. The epithelial cells are rich in rough endoplasmic reticulum, mitochondria and small vacuoles. The vasa deferentia, especially in G. betulae, are filled with an electron-dense secretion which, as was shown by histochemical staining, contains proteins and polysaccharides. We suggest that the maximum secretory activity of these epithelial cells occurs, as does spermatogenesis, during larval stages, so that the short living adult males are immediately ready for copulation as in other aphids with normal-sized males.  相似文献   

9.
Plant microRNAs (miRNAs) are crucial for the regulation of gene expression, which is involved in almost all the important biological processes. In the cytoplasm, the miRNA strand is selectively incorporated into a specific Argonaute (AGO)-associated gene silencing complex, while the miRNA* is degraded rapidly. Thus, most miRNA*s were thought to be biologically meaningless. Interestingly, several recent reports in both plants and animals have shaken this notion. Many miRNA*s were demonstrated to possess regulatory roles in gene expression. However, the low accumulation levels of most miRNA*s raise the question whether the activities of this small RNA (sRNA) species are widespread in plants. Here, by using publicly available sRNA high-throughput sequencing data, we found that the accumulation levels of several miRNA*s could be much higher than those of their miRNA partners in certain organs, mutants and/or AGO-associated silencing complexes of both Arabidopsis (Arabidopsis thaliana) and rice (Oryza sativa). Based on target prediction and degradome sequencing data-based validation, some of these highly accumulated miRNA*s were indicated to possess cleavage-based potential regulatory role on certain targets. Besides, some interesting biological interpretations were obtained based on the accumulation patterns of the miRNA*s, the annotations of the target genes, and literature mining. Taken together, the expanded list of the highly accumulated miRNA*s along with their potential target genes discovered in this study further strengthened the current notion that certain members of the miRNA* species are biologically relevant, which needs further inspection.  相似文献   

10.
11.
Ambrosia beetles (Coleoptera: Scolytinae) are associated with strictly entomochoric and mutualistic fungi. We studied the mycobiota associated with Scolytodes unipunctatus, ambrosia beetles that infest Cecropia trees in Central America. Isolates were characterized using morphology and rDNA sequences (ITS region, LSU, and SSU rDNA). Four species are described here: Raffaelea scolytodis sp. nov. (Ophiostomatales), Gondwanamyces scolytodis sp. nov., Custingophora cecropiae sp. nov., and Graphium sp. (Microascales). The genus Custingophora is emended to include Knoxdaviesia anamorphs of Gondwanamyces based on uniformity of DNA sequences and phenotype.  相似文献   

12.
The ultrastructure of septa and septum-associated septal pore caps are important taxonomic markers in the Agaricomycotina (Basidiomycota, Fungi). The septal pore caps covering the typical basidiomycetous dolipore septum are divided into three main phenotypically recognized morphotypes: vesicular-tubular (including the vesicular, sacculate, tubular, ampulliform, and globular morphotypes), imperforate, and perforate. Until recently, the septal pore cap-type reflected the higher-order relationships within the Agaricomycotina. However, the new classification of Fungi resulted in many changes including revision of existing and addition of new orders. Therefore, the septal pore cap ultrastructure of more than 325 species as reported in literature was related to this new classification. In addition, the septal pore cap ultrastructures of Rickenella fibula and Cantharellus formosus were examined by transmission electron microscopy. Both fungi have dolipore septa associated with perforate septal pore caps. These results combined with data from the literature show that the septal pore cap-type within orders of the Agaricomycotina is generally monomorphic, except for the Cantharellales and Hymenochaetales.It appears from the fungal phylogeny combined with the septal pore cap ultrastructure that the vesicular-tubular and the imperforate type both may have arisen from endoplasmic reticulum. Thereafter, the imperforate type eventually gave rise to the perforate septal pore cap-type.  相似文献   

13.
Until now, five species of the subgenus Uroleucon (Uromelan) have been recognized in Korea. This is the first report of Uroleucon (Uromelan) adenophorae (Matsumura, 1918) occurring on Adenophora triphylla (Campanulaceae) in Gangwon-do, South Korea. Host plants are reviewed and an identification key to species is presented for six Uroleucon (Uromelan) species from the Korean Peninsula.  相似文献   

14.
The section Brunnei was extensively studied based on material from North Europe. To stabilise the nomenclature we studied the relevant types of taxa included in this section. Phylogenetic relationships and species limits were investigated using rDNA ITS sequences and the results were compared with the morphological data. We recognised 11 species: Cortinarius brunneus, C. clarobrunneus comb. nov., C. coleoptera, C. ectypus, C. gentilis, C. glandicolor (neotypified), C. pseudorubricosus, and four species described as new C. caesiobrunneus, C. albogaudis, C. carabus, and C. cicindela. They are described here and their taxonomy, ecology, distribution, and relationships are discussed. In addition, a key to species of the section Brunnei is provided. A total of 77 new sequences of 11 species are published including nine type sequences. Also the taxonomic assignments of sequences in the public databases belonging to the section Brunnei are revised.  相似文献   

15.
16.
Survival rates of Ascosphaera aggregata and Ascosphaera apis over the course of a year were tested using different storage treatments. For spores, the storage methods tested were freeze-drying and ultra-low temperatures, and for hyphae, freeze-drying, agar slants, and two methods of ultra-low temperatures. Spores of A. aggregata and A. apis stored well at −80 °C and after freeze-drying. A. aggregata hyphae did not store well under any of the methods tested while A. apis hyphae survived well using cryopreservation. Spores produced from cryopreserved A. apis hyphae were infective. Long-term storage of these two important fungal bee diseases is thus possible.  相似文献   

17.
Germinoma is a gonadal neoplasm originating from progenitor cells in germinal epithelium. Frequently described in some populations of bivalve molluscs, to our knowledge, germinoma has never been reported in gastropods so far. In this paper we describe the histopathological findings of some atypical cellular masses, originating in the undifferentiated germ cell layer in the male gonads of a limpet (Patella coerulea), whose morphological appearance resembled that of a germ cell tumor. The abnormal, and independent growth with no evidence of maturation of the undifferentiated and atypical germ cells, the limited number of follicles involved (n < 10%) and the absence of tissue invasion, supported a diagnosis of Stage 1 germinoma.  相似文献   

18.
Outbreaks of an unidentified ciliate have occurred on several occasions in blue crabs from Chesapeake Bay held during winter months in flow-through systems. The parasite was initially thought to be Mesanophrys chesapeakensis, but molecular analysis identified it as Orchitophyra stellarum, a facultative parasite of sea stars (Asteroidea). We investigated the host-parasite association of O. stellarum in the blue crab host. Crabs were inoculated with the ciliate, or they were held in bath exposures after experimentally induced autotomy of limbs in order to determine potential mechanisms for infection. Crabs inoculated with the ciliate, or exposed to it after experimental autotomy, rapidly developed fatal infections. Crabs that were not experimentally injured, but were exposed to the ciliate, rarely developed infections; thus, indicating that the parasite requires a wound or break in the cuticle as a portal of entry. For comparative purposes, fiddler crabs, Uca minax, were inoculated with the ciliate in a dose-titration experiment. Low doses of the ciliate (10 per crab) were sometimes able to establish infections, but high intensity infections developed quickly at doses over 500 ciliates per crab. Chemotaxis studies were initiated to determine if the ciliate preferentially selected blue crab serum (BCS) over other nutrient sources. Cultures grown on medium with BCS or fetal bovine serum showed some conditioning in their selection for different media, but the outcome in choice experiments indicated that the ciliate was attracted to BCS and not seawater. Our findings indicate that O. stellarum is a facultative parasite of blue crabs. It can cause infections in exposed crabs at 10–15 °C, but it requires a portal of entry for successful host invasion, and it may find injured hosts using chemotaxis.  相似文献   

19.
A high-performance liquid chromatographic method is described for the determination of (R)- and (S)-alprenolol and (R)- and (S)-metoprolol in human plasma. Separation of the enantiomers was accomplished after preparation of diastereomeric derivatives with symmetrical anhydrides of tert.-butoxycarbonyl-l-leucine followed by treatment with trifluoroacetic acetic acid at 0°C to remove the tert.-butoxycarbonyl group. The separations of the diastereomeric derivatives were performed using a reversed-phase system with μBondapak C15 as support and phosphate buffer pH 3.0 with the addition of acetonitrile as the mobile phase. High stability of the chromatographic system was achieved.The reproducibilities in the determination of (R)- and (S)-alprenolol and (R)- and (S)-metoprolol in human plasma were 9.4 and 9.8% (relative standard deviation) for alprenolol and metoprolol, respectively, at drug levels of 0.5 ng/ml.In two subjects who received single oral doses of alprenolol (100-mg tablet) and metoprolol (50-mg tablet) the plasma levels of the (R)-isomers were lower than for the (S)-isomers.  相似文献   

20.
The chemosystematic value of UV-absorbing leaf constituents was considered in previously uncharacterised representatives of Aloe section Pictae, the problematic maculate species complex. Comparative data indicate that the anthrone C-glycoside, 6′-malonylnataloin (7-hydroxychrysaloin 6′-O-malonate) is typical of maculate species in East Africa, but is unconvincing as a synapomorphy for section Pictae. A naphthalene derivative found widely in Aloe, plicataloside, was detected in Aloe greatheadii. Biogeographical trends were observed in the occurrence of the flavonoids isoorientin (luteolin-6-C-glucoside) and isovitexin (apigenin 6-C-glucoside). Isoorientin is a common constituent of tropical and sub-tropical species of Aloe, whereas isovitexin is restricted to a few southern African species. Isoorientin and isovitexin co-occur in the southern African maculate species Aloe parvibracteata, and the disjunct West African maculate species, Aloe macrocarpa. This is the first report of isoorientin and isovitexin in maculate species of Aloe; the presence of flavonoids in section Pictae is of taxonomic interest.  相似文献   

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