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1.
Monitoring phlebotomine sandflies in urban areas is key for epidemiological studies in susceptible populations. This paper describes sandfly fauna that were present in an urban area of the municipality of Tapachula, Chiapas, Mexico, and were captured with Shannon and CDC light traps. During February and March of 2014, 1,442 sandflies were captured, specifically Lutzomyia cruciata (Coquillet) (98.8%), Lutzomyia cayennensis cayennensis (Floch and Abonnenc) (0.8%), Lutzomyia chiapanensis (Dampf) (0.3%) and Lutzomyia atulapai (De León) (0.1%). Lu. cruciata was the most abundant and the most frequently trapped species. This is the first record of its remarkable ability to adapt to urban green areas. The three other species trapped represent new records of geographic distribution for the study region. These results indicate the need to establish measures for reducing both human contact with this vector and the risk of possible sites of infection.  相似文献   

2.
3.
To improve the practical usefulness of the firefly luciferase, we performed gene chimerization between Photinus pyralis luciferase and a thermostable variant of Luciola cruciata luciferase. One chimeric luciferase showed low K(m) value for substrate ATP and similar stability to thermostable L. cruciata luciferase. We then introduced random mutations in the corresponding gene and screened for increased catalytic efficiency. Amino acid replacement of Thr219, Val239 and Val290 affected the kinetic parameters. Therefore, we combined these three mutations. One mutant, ABcT219I,V239I, showed high catalytic efficiency comparable to P. pyralis luciferase and high stability similar to thermostable L. cruciata luciferase. The pH-dependence of the bioluminescence emission spectra was also examined. In contrast to wild-type firefly luciferases characterized to date, the mutant did not show the pH-dependent red spectrum shift.  相似文献   

4.
The Genji firefly, Luciola cruciata, is divided into two ecological types, the fast-flash and slow-flash types, on the basis of the interflash interval of mate-seeking males. To evaluate the evolutionary origin of the two types, 62 populations were examined by restriction fragment length polymorphism analysis of the mitochondrial cytochrome oxidase (CO) II gene. As a result, 19 haplotypes were detected, and their distributions were indigenous to local areas. Phylogenetic trees constructed from sequence comparison of the haplotypes revealed three major clades (I, II, and III). The boundary of haplotypes between clades I and II is approximately concordant with the geological structure of the Japanese Islands, which is a great rupture zone called the Fossa Magna, and the distribution of haplotypes in clades III and I-II corresponds to the Kyushu and Honshu-Shikoku Islands, respectively. The results suggest a vicariant scenario in which current L. cruciata diversity would have arisen from phylogenetic separations subsequent to the formation process of the Japanese Islands based on the molecular clock. The CO II gene trees also suggested that the fast-flash type should be considered an ancestral form, while the slow-flash type would be a derived one. The divergence time between the slow- and the fast-flash types is estimated to be about 4.6 to 2.0 mya (the Pliocene epoch).  相似文献   

5.
利用PCR与TAlL-PCR方法,从半月苔(Lunularia cructata(L.)Dum.ex Lindb)中获得了一段长约l 000 bp的基因片段,它与已知的CHS基因在核苷酸水平上的相似性大于56%,在氨基酸水平上的相似性大于60%,所推断的氨基酸序列中酶反应的4个催化位点与已知晶体结构的紫花苜蓿MCHS2A上的催化位点相同,首次证明了苔类植物中可能存在类CHS基因,将CHS基因的起源时间推到苔藓类植物出现之前.以该序列和两种蕨类植物(Psilotumnudum(L.)Griseb.和Equisetum arvense L.)的CHS序列作为外类群,应用邻接法、最大简约法和最大似然法分别构建了被子植物的CHS的分子系统树.结果表明,大部分科中的CHS分布在不同的分支上,而十字花科、可科和禾本科各自聚成一个单系类群.以邻接树为依据,对茄科、旋花科和菊科的CHS基因进行了相对碱基替换速率的检测,发现这三个科内或科间序列的替换速率不一致.被子植物的CHS基因在基因拷贝数目、碱基替换速率以及重复/丢失事件的发生上都存在较大的差异,这种差异可能与被子植物的生活史、生活环境、花的特性以及对外界的防御系统等的多样性相关.  相似文献   

6.
Shoots of micropropagated Gentiana acaulis, G. cruciata, G. lutea, and G. purpurea were inoculated with suspensions of Agrobacterium rhizogenes cells, strains ATCC 15834 or A4M70GUS. Adventitious roots appeared at the sites of inoculation in all 4 species. Root tips were excised and cultured on growth regulator-free media for 2-6 years. They exhibited very high branching and plagiotropism. Spontaneous bud initiation occurred in roots of G. cruciata. Roots of G. lutea, G. acaulis and G. purpurea were cultured on media with high kinetin concentration, which induced the formation of friable callus tissues. Only in G. purpurea were these calluses organogenic. Regenerated shoots of G. cruciata and G. purpurea gave rise to plants, that displayed the typical phenotypes of A. rhizogenes-transformed plants: short internodes and rolled leaves. In the roots of G. acaulis and G. cruciata, transformed with A. rhizogenes A4M70GUS, a positive reaction with X-gluc indicated the activity of β-glucuronidase. The DNA extracted from hairy roots and from the roots of transgenic plants hybridized with the appropriate genomic probes in Southern blotting. This is taken as evidence of the stable genetic transformation in the 4 Gentiana species. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

7.
CHS基因起源初探及其在被子植物中的进化分析   总被引:6,自引:0,他引:6  
利用PCR与TAIL-PCR方法,从半月苔(Lunulariacruciata(L.)Dum.exLindb.)中获得了一段长约1000bp的基因片段,它与已知的CHS基因在核苷酸水平上的相似性大于56%,在氨基酸水平上的相似性大于60%,所推断的氨基酸序列中酶反应的4个催化位点与已知晶体结构的紫花苜蓿MCHS2A上的催化位点相同,首次证明了苔类植物中可能存在类CHS基因,将CHS基因的起源时间推到苔藓类植物出现之前。以该序列和两种蕨类植物(Psilotumnudum(L.)Griseb.和EquisetumarvenseL.)的CHS序列作为外类群,应用邻接法、最大简约法和最大似然法分别构建了被子植物的CHS的分子系统树。结果表明,大部分科中的CHS分布在不同的分支上,而十字花科、豆科和禾本科各自聚成一个单系类群。以邻接树为依据,对茄科、旋花科和菊科的CHS基因进行了相对碱基替换速率的检测,发现这三个科内或科间序列的替换速率不一致。被子植物的CHS基因在基因拷贝数目、碱基替换速率以及重复/丢失事件的发生上都存在较大的差异,这种差异可能与被子植物的生活史、生活环境、花的特性以及对外界的防御系统等的多样性相关。  相似文献   

8.
Kai A  Yoshii Y  Nakayama T  Inouye I 《Protist》2008,159(3):435-457
A new heterokontophyte alga, Aurearena cruciata gen. et sp. nov., was isolated from sandy beaches in Japan. Isolates were characterized by light and electron microscopy, spectroscopy of pigment composition, and molecular phylogenetic analyses using 18S rDNA and rbcL. The alga usually possessed a cell wall but also retained two heterokont flagella beneath the cell wall. Each walled cell first produced only a single flagellate cell that subsequently divided into two flagellate cells. Electron-opaque vesicles, possibly associated with cell wall formation, were observed beneath the cell membrane. The chloroplast consisted of two compartments, each enclosed by a chloroplast envelope and the inner membrane of the chloroplast endoplasmic reticulum; these two compartments were surrounded by a common outer membrane of chloroplast endoplasmic reticulum. Molecular phylogenetic trees suggested that this alga was a new and independent member of the clade that included the Phaeophyceae and Xanthophyceae (PX clade). A new class, Aurearenophyceae classis nova was proposed for A. cruciata.  相似文献   

9.
During mating, many male insects transfer sperm packaged within a spermatophore that is produced by reproductive accessory glands. While spermatophores have been documented in some North American fireflies (Coleoptera: Lampyridae), little is known concerning either production or transfer of spermatophores in the aquatic Luciola fireflies widespread throughout Asia. We investigated this process in Japanese Luciola lateralis and L. cruciata by feeding males rhodamine B, a fluorescent dye known to stain spermatophore precursors. We then mated males with virgin females, and dissected pairs at various timepoints after mating. In both of these Luciola species, spermatophores were produced by three pairs of male accessory glands and were transferred to females during the second stage of copulation. Male spermatophores were highly fluorescent, and were covered by a thin outer sheath; a narrow tube leading from an internal sperm-containing sac fit precisely into the female spermathecal duct, presumably for sperm delivery. Both L. lateralis and L. cruciata females have a spherical spermatheca as well as a highly extensible gland where spermatophore breakdown commences by 24h post-mating. Similar reproductive anatomy was observed for both sexes in Luciola ficta from Taiwan. These results suggest that nuptial gifts may play an important role in many firefly-mating systems.  相似文献   

10.
Species-specific flash patterns in firefly species are important for the investigation of the evolution of Lampyridae. Since nitric oxide synthase (NOS) is one of the key enzymes controlling flash patterns, we determined the cDNA sequences of NOS in the Japanese fireflies Luciola lateralis and L. cruciata. The identity of the NOS sequences was very high between these 2 species. Firefly NOS also exhibited a high identity with those of other insect species, and the cofactor-binding domains were particularly well conserved. Many negatively selected sites were detected throughout the NOS sequences; however, no positive selection was detected. The phylogenetic relationship of insect NOS was different from that of the general classification system, although the lineages corresponded to the major recognized taxonomic groups.  相似文献   

11.
The water transport response during freezing of sperm cells of Morone chrysops (white bass, WB) was obtained using a shape-independent differential scanning calorimeter (DSC) technique. Sperm cell suspensions were frozen at a cooling rate of 20 degrees C/min in two different media: (1) without cryoprotective agents (CPAs), or (2) with 5% (v/v) dimethyl sulfoxide (Me2SO). For calculations, the sperm cell was modeled as a cylinder of length 24.8 microm and diameter of 0.305 microm, while the osmotically inactive cell volume (Vb) was assumed to be 0.6 Vo, where Vo was the isotonic or the initial cell volume. By fitting a model of water transport to the experimentally determined water transport data, the best fit membrane permeability parameters (reference membrane permeability to water, Lpg or Lpg[cpa] and the activation energy, ELp or ELp[cpa]) were determined, and ranged from Lpg = 0.51-1.7 x 10(-15) m3/Ns (0.003-0.01 microm/min-atm), and ELp = 83.6-131.3 kJ/mol (20.0-31.4 kcal/mol). The parameters obtained in this study suggest that the optimal rate of cooling for M. chrysops sperm cells is approximately 22 degrees C/min, a value that compares closely with experimentally determined optimal rates of cooling (approximately 16 degrees C/min).  相似文献   

12.
13.
We have cloned a cDNA encoding Luciola lateralis (a common firefly in Japan) luciferase from a cDNA library of lantern poly(A)+ RNA, using a cDNA of L. cruciata (another common firefly in Japan) luciferase as a probe. The primary structure of L. lateralis luciferase deduced from the nucleotide sequence was shown to consist of 548 amino acids with a molecular weight of 60,132. Sequence comparison indicates that L. lateralis luciferase has significant sequence identity (94%) to L. cruciata luciferase, and that it has less sequence similarity (67%) to Photinus pyralis (a North American firefly) luciferase. The isolated cDNA clone, when introduced into Escherichia coli, directed the synthesis of enzymatically active luciferase under the control of the lacZ promoter.  相似文献   

14.
This study deals with the pollination ecology of a population Gentiana cruciata in the Vitosha Mts., SW Bulgaria. Fortyeigth % of flowers bagged at bud stage developed into fruits. Flowers in the investigated population was visited actively by insects. Halictus bees constituted 34.5% of all insect visits. Visits by bumblebees (mainly Bombus hortorum) constituted 18.9% of all insect visits. All open-pollinated flowers set fruit capsules and their seed set was high. The pollination biology of this population (at the south-westem part of the distributional range of the species) is compared to that of populations in The Netherlands (at the north-western margin of the distribution range of the species).  相似文献   

15.
The growth of axillary shoots was initiated on nodal stem segments, excised from aseptically grown seedlings of Gentiana acaulis L., G. cruciata L., G. lutea L. and G. purpurea L. In later subcultures, a basal callus tissue developed on the shoots, giving rise to de novo formed buds. Optimum benzyladenine and indoleacetic acid combinations for shoot development were established. They were slightly different in the four species. From 35-70% of shoots rooted spontaneously, except in G. lutea, in which adventitious roots were induced by applying naphthaleneacetic acid. It was conduded that the four Gentiana species were amenable to propagation in vitro. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

16.
URSULA MUNRO  JOHN A. MUNRO 《Ibis》1998,140(4):599-604
The Yellow-faced Honeyeater Lichenostomus chrysops is a diurnal migrant which covers short to moderate distances in eastern Australia. Recordings of locomotor activity of nine wild-caught Yellow-faced Honeyeaters kept under a simulated natural photoperiod in the laboratory over a period of 13 months showed that these birds exhibit a distinct seasonal pattern in hopping activity. Two major seasonal peaks of enhanced activity were observed. The first occurred during the time of autumn migration in March to July, while a second peak from September to December coincided roughly with spring migration. Daily activity patterns of Yellow-faced Honeyeaters showed two major peaks. The first peak ranged from the early morning hours to approximately early afternoon, while a second smaller peak was observed in the late afternoon. During their migratory periods in spring and autumn, the morning as well as the afternoon peaks were considerably higher than in months when Yellow-faced Honeyeaters do not migrate.  相似文献   

17.
Ichthyobodo necator is an important fish ectoparasite with a broad host and ecological range. A novel method, involving the use of an anesthetic, allowed the collection of large numbers of parasites from the skin and gills of hybrid striped bass (Morone saxatilis male x M. chrysops female). Genomic DNA from these samples was used to amplify and clone the 18S rRNA gene. The 18S rRNA gene was similarly cloned from Bodo caudatus, Bodo edax, Bodo saltans, an unidentified Bodo species, and Dimastigella trypaniformis. The resulting sequences were aligned with other representative kinetoplastid species using pileup and similarities in secondary structure. Phylogenetic relationships within the suborder Bodonina and representatives of the suborder Trypanosomatina were determined using maximum-likelihood statistics. The phylogenetic analyses strongly supported the order Kinetoplastida as a monophyletic assemblage consisting of at least two major lineages. One lineage consisted exclusively of L. necator, indicating that it may represent a new suborder. The second lineage consisted of all other kinetoplastid species. This second lineage appeared to contain at least 8 bodonine sublineages, none of which correlated with currently recognized families. For three sublineages, there was a close correspondence between the 18S phylogeny and the classical taxonomy of Dimastigella, Rhynchobodo, and Rhynchomonas. In contrast, Bodo and Cryptobia were polyphyletic, containing species in two or more sublineages that may represent separate genera.  相似文献   

18.
The peridinian dinoflagellate Amyloodinium ocellatum was propagated by serial passage in clownfish (Amphiprion ocellaris) and hybrid striped bass (Morone chrysops X Morone saxatilis). Each 25-50-mm fish was exposed to 4,000-6,000 dinospores in 400 ml of artificial seawater for 30 min. Two days after exposure, trophonts were harvested by immersing the fishes in fresh water. After encystment, tomonts were axenized by multiple washes with sterile distilled water and sterile artificial seawater containing penicillin and streptomycin, and then incubated in the antibiotic solution. High yields of both tomonts and dinospores of the same sizes and ages were obtained, and host mortalities were eliminated. Microbial growth in incubating cultures was inhibited until after dinospores had emerged from tomonts, and dinospores remained infective for at least 4 days at 26 C.  相似文献   

19.
An in vitro phagocytosis assay was developed for hybrid striped bass (Morone saxatilis x Morone chrysops), using cells collected from the peritoneal cavity of this fish. The findings indicated that: (1) 10 days following a single intraperitoneal injection (1 ml) of Freund's incomplete adjuvant (FIA) was an appropriate time for collecting suitable working concentrations (5.3+/-4.0 x 10(7) cells ml(-1)) of peritoneal phagocytes (83.7+/-1.5% macrophages) from these hybrids held at 23 degrees C; (2) these cells phagocytosed latex beads (polystyrene microspheres 3.12 microm in diameter) after 30 min of in vitro incubation at room temperature (25+/-1 degrees C). The phagocytic ability and phagocytic capacity in a washed adherent layer exposure system were 67.2+/-2.76% and 4.14+/-0.35 beads phagocyte(-1), respectively. These results strongly suggest that a simple methodology, including baseline data serving as guidelines, is now available for conducting in vitro phagocytosis assays in this hybrid.  相似文献   

20.
Luciferases of Luciola cruciata and Luciola lateralis, LcL and LlL, were purified to homogeneity by ammonium sulfate precipitation, gel-filtration column chromatography, and hydroxyapatite HPLC. The molecular masses of the enzymes determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) were both 62 kDa, almost identical to that of Photinus pyralis (PpL). LcL was found to be similar to PpL in thermal stability, pH stability, and the wavelength of maximum light intensity. LlL was superior to LcL and PpL in thermal and pH stability, and the reaction catalyzed by LlL emits green light with a peak intensity at 552 nm, which is 10 nm shorter in wavelength than those of PpL and LcL.  相似文献   

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