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1.
为探讨piggyBac转座子在鱼类动物中应用的可能性,以包含家蚕(Bombyx mori)肌动蛋白3启动子驱动的增强型绿色荧光蛋白(enhance green fluorescent protein,EGFP)基因的piggyBac质粒为载体,以及一个包含piggyBac转座酶的辅助质粒,采用显微注射的方法将其导入叉尾斗鱼(Macropodusopercularis)受精卵中,利用PCR技术证实了piggyBac转座子能够介导EGFP基因进入叉尾斗鱼基因组,并能够稳定遗传到下一代,符合孟德尔遗传规律。EGFP基因遗传到G1代的阳性鱼占交配鱼比率,即外源基因整合率为12.30%。实验证明,piggyBac质粒有可能成为水产动物转基因实验的新型载体。  相似文献   

2.
The behavioural effects of morphine on fish (Macropodus opercularis) were studied by an ethopharmacological analysis. For this purpose active and passive behavioural units were observed.The results show that morphine treatment had a stimulating effect. However, the treatment resulted not in a general enhancement of active behavioural units, but in a selective increase of some of them, such as swimming and erratic behaviour, or in stereotyped behaviours, such as circling. By contrast, high dosages of morphine resulted in a decrease of escape and of standing under the surface behaviours.  相似文献   

3.
Starch-slab gel electrophoresis showed two patterns of peroxidase isoenzymes in the polymorphic taxon. Xanthium strumarium L. The “strumarium” morphological complex (X. strumarium, in the sense of Millspaugh and Sherff), the putative indigenous plants of the Old World, contained a different pattern from that shown by putative introductions from the New World. Experimental F1 hybrids between “strumarium” and other complexes, “italicum-pennsylvanicum”, “chinense”, “oviforme” and “cavanillesii”, had the peroxidase pattern of the American plants. These peroxidase isoenzyme patterns were not influenced by the environmental growing conditions, but, along with partial genetic incompatibility, support the taxonomic separation of X. strumarium from other taxa of section Euxanthium.  相似文献   

4.
Lindernia procumbens and L. dubia are common annual weeds in flooded rice fields of Japan. Two subspecies of L. dubia, subsp. major and subsp. dubia, are usually recognized in Japan but they are both regarded as synonyms of L. dubia elsewhere. In a cluster analysis based on AFLP, most L. dubia subsp. major formed a separate cluster from L. dubia subsp. dubia although 11% of haplotypes classified using AFLP were not coincident with classification using the shape of leaf bases, which is the commonly used identification trait. Artificial F1 plants between L. procumbens and L. dubia subsp. major, and between L. procumbens and L. dubia subsp. dubia did not produce seed. Forty percent of capsules produced by F1 plants from these two subspecies were slimmer and 80% pollen were sterile in slimmer capsules. However, seed number of most F1 capsules was not different from that of self-fertilized plants, suggesting that there was no complete reproductive isolation between the subspecies. Natural hybridization of these subspecies may have occurred but we are not aware of it because F1 plants are rare and F2 plants are indistinguishable from these subspecies.  相似文献   

5.
Morphologically diverse plants in a wild population of Xanthium strumarium in eastern Texas produced widely variant combinations of sesquiterpene lactones. Some plants showed a preponderance of xanthinin and related compounds, xanthanol and xanthatin, while others a predominance of stereoisomers, xanthumin, xanthumanol and deacetoxylxanthumin. Some plants produced only one sesquiterpene lactone and other plants yielded various mixtures of xanthinin, xanthumin and related compounds, including xanthinosin and/or tomentosin. Experimental hybridization between plants containing primarily xanthinin and plants containing xanthumin, but originating in diverse parts of the world, yielded F1 progenies with xanthanol and/or xanthumanol as the predominant sesquiterpenoid component. The F2 generation showed segregation of the xanthinin, xanthumin and related compounds. The Texas population occurs in an area where the “italicum” (xanthinin-predominants) and “chinense” (xanthumin-predominant) morphological complexes are sympatric. The diverse patterns of sesquiterpene lactones in the Texas population probably resulted from the natural hybridization of morphological complexes that originally were spatially isolated.  相似文献   

6.
Genetic diversity and geographic distribution of taxon-specific RAPD markers was examined in ten local populations of the house mouse Mus musculus (n = 42). The house mice were generally characterized by moderate genetic variation: polymorphism P 99 = 60%, P 95 = 32.57%; heterozygosity H = 0.12; the observed allele number n a = 1.6; the effective allele number n e = 1.18; the within-population differentiation ?s = 0.388; and Shannon index I = 0.19. The degree of genetic isolation of individual local populations was greatly variable. The genetic subdivision index G st varied from 0.162 to 0.770 at the gene flow of Nm = 2.58?0.149, while the among-population distances D N varied from 0.026 to 0.178. The largest part of the genetic diversity was found among the populations (H T = 0.125), while the within-population diversity was twice lower (H S = 0.06). The samples examined were well discriminated relative to the sets of RAPD markers. The character distribution pattern provided conditional subdivision of the mice into the “western” and the “eastern” groups with the putative boarder along the Baikal Lake. The first group was characterized by the prevalence of the markers typical of M. m. musculus and M. m. domesticus. The second group was characterized by the prevalence of the markers typical of M. m. musculus, M. m. gansuensis, M. m. castaneus, M. m. domesticus, and M. m. wagneri. The genotype of the nominative subspecies M. m. musculus was background for all populations. In the populations examined some of earlier described subspecies-specific molecular markers were found at different frequencies, pointing to the involvement of several subspecies of M. musculus in the process of hybridization.  相似文献   

7.
Melipona quadrifasciata is a stingless bee widely found throughout the Brazilian territory, with two recognized subspecies, M. quadrifasciata anthidioides, that exhibits interrupted metasomal stripes, and M. quadrifasciata quadrifasciata, with continuous metasomal stripes. This study aimed to estimate the genetic variability of these subspecies. For this purpose, 127 colonies from 15 Brazilian localities were analyzed, using nine species-specific microsatellite primers. At these loci, the number of alleles ranged from three to 15 (mean: 7.2), and the observed heterozygosity (Ho) ranged from 0.03–0.21, while the expected heterozygosity (He) ranged from 0.23–0.47. The genetic distances among populations ranged from 0.03–0.45. The FST multilocus value (0.23) indicated that the populations sampled were structured, and the clustering analysis showed the formation of two subgroups and two more distant populations. The first group contained the subspecies M. quadrifasciata quadrifasciata, and the other, the subspecies M. quadrifasciata anthidioides and the two M. quadrifasciata populations with continuous metasomal stripes from northern Minas Gerais. These results confirmed that the yellow metasomal stripes alone are not a good means for correctly identifying the different subspecies of M. quadrifasciata.  相似文献   

8.
Chiu J.-K., Ong S.-J., Yu J.-C., Kao C.-Y. and Iuima T. 1981. Susceptibility of Oncomelania hupensis formosana recombinants and hybrids with Oncomelania hupensis nosophora to infection with Schistosoma japonicum. International Journal for Parasitology11: 391–397. Three generations of Oncomelania hupensis formosana recombinants were produced by mating the Kaohsiung race with the Ilan and Changhua races of the snails. F2 and F3 recombinants were produced by back-crossing F1 and F2 with Kaohsiung O. h. formosana. Subsequently, susceptibility of recombinants to infection with the original strain of Schistosoma japonicum, Ilan or Changhua strain, was investigated. Results indicated that susceptibility of recombinants declined steadily generation by generation. Marked decline of infectivity was observed for Kaohsiung-Ilan recombinants as compared with Kaohsiung-Changhua recombinants. For example, the overall infection rate of Kaohsiung-Ilan F1 recombinants was 7.3 % with a 51.4 % of control snails. The same figures for F2 were 4.2 and 52.6%, and 1 and 40.3 % for F3. On the other hand, the overall infection rate of Kaohsiung-Changhua F1 recombinants was 21.9% with a 46.9% of control snails; and 11.9 and 50.3 % for F2; and 7.6 and 33.2% for F3. The F3 hybrids of Oncomelania hupensis nosophora from Japan and O. h. formosana from Kaohsiung and Ilan were also produced, and susceptibility with the Japanese strain of S. japonicum was studied. A highly significant decline of susceptibility was observed among hybrids (4.4%) in contrast with control snails (85.6 %).Feasibility of applying O. h. formosana in biological control of S. japonicum was discussed. One must determine in the laboratory, prior to application, which race of O. h. formosana should be used depending on the Oncomelania snails of an endemic area. For S. japonicum prevalent in Yamanashi, Japan, the Ilan race of O. h. formosana was found to be better choice than the Kaohsiung race of the snails.  相似文献   

9.
Two geographically and reproductively isolated populations each of Chlamys opercularis and of Chlamys varia are compared with respect to polymorphism at the phosphoglucose isomerase (PGI) locus. One population of C. varia is further sub-divided into sub-littoral and inter-tidal samples. From the results it is inferred that PGI is a dimeric molecule, controlled by five alleles in C. varia and by at least four alleles in C. opercularis. acting at a single locus. The alleles recognised for C. opercularis have identical electrophoretic mobility as four of those seen in C. varia. The two populations of C. varia are remarkably similar, as were their habitats. However, the sub-littoral sample does show a lesser degree of homozygosity than the inter-tidal sample of the same population. The two populations of C. opercularis differ significantly and represent two separate and identifiable ‘races’. C. varia exhibits a much greater degree of genetic variability than the deep sub-littoral species, C. opercularis indicating that a more stable environment regulates a more monomorphic species.  相似文献   

10.
采用微卫星技术研究了板栗(Castanea mollissima)和锥栗(C. henryi)同域分布居群的空间遗传结构, 探讨了它们的遗传变异空间分布特征及其形成机制。结果表明,采用的7个微卫星在两物种中共扩增出173个等位基因,两物种都具有较高的遗传多样性且种间遗传分化水平较低(FST=0.051), 但空间自相关分析揭示板栗和锥栗在同域居群中具有不同的空间遗传结构,锥栗在100 m内有空间遗传结构,而板栗没有;同时,基于亲缘关系系数FijSp统计值也显示锥栗具有比板栗更强的空间遗传结构(板栗的Sp=0.002;锥栗的Sp=0.018)。居群遗传变异的空间结构是其传粉和种子散播及生境共同作用的结果,其中种子的近距离散播和居群密度可能是主要的因素。板栗和锥栗居群在小尺度上空间遗传结构的差异可能反映了它们种子的大小及扩散过程的差异。  相似文献   

11.
Analysis, using the polymerase chain reaction (PCR), restriction enzyme endonuclease analysis (REA), protein profile patterns, random amplification of polymorphic DNA (RAPD) fingerprinting, 16S rRNA gene sequencing and antisera growth inhibition tests, of 22 strains of Mycoplasma mycoides subsp. mycoides Large Colony type (MmmLC) and eight strains of M. mycoides subsp. capri (Mmc) are presented, along with a summary of comparative data from the literature for over 100 strains, all of which supports the reclassification of the MmmLC and Mmc strains into the single subspecies, M. mycoides subspecies capri.  相似文献   

12.
Genetic differentiation of six subspecies of the house mouse Mus musculus (Mus musculus musculus, M. m. domesticus, M. m. castaneus, M. m. gansuensis, M. m. wagneri, and M. m. ssp. (bactrianus?) was examined using RAPD-PCR analysis. In all, 373 loci of total length of about 530 kb were identified. Taxonspecific molecular markers were detected and the levels of genetic differences among the subspecies were estimated. Different degree of subspecific genetic differentiation was shown. The most similar subspecies pairs were M. m. castaneus-M. m. domesticus and M. m. musculus-M. m. gansuensis. In our phylogenetic reconstruction, M. m. wagneri proved to be most different from all the other subspecies. Genetic distances between it and other subspecies were two-to threefold higher than those between the “good”species of the subgenus Mus (e.g., between M. m. musculus and M. spicilegus, M. musculus and M. abbotti). The estimates of genetic similarity and the phylogenetic relationships between six house mouse subspecies inferred from RAPD partially conformed to the results based on cytogenetic and allozyme data. However, they were considerably different from phylogenetic reconstructions based on sequencing of the control mtDNA region, which reflects mutual inconsistency of different systems of inheritance.  相似文献   

13.
Quantifying patterns of genetic diversity and differentiation among populations of Arctic birds is fundamental for understanding past and ongoing population processes in the Arctic. However, the genetic differentiation of many important Arctic species remains uninvestigated. Here, phylogeography and population genetics were examined in the worldwide population of a small seabird, the little auk (dovekie, Alle alle)—the most numerous avian species of the Arctic ecosystem. Blood samples or feathers were collected from 328 little auks (325 from the nominate subspecies and 3 from the A. a. polaris) in nine main breeding aggregations in the northern Atlantic and one location from the Pacific Ocean. The mtDNA haplotypes of the two subspecies were not segregated into separate groups. Also, no genetic structure was found within the nominate race based on microsatellite markers. The level of genetic differentiation among populations was low yet significant (mean F ST = 0.005). Some pairwise F ST comparisons revealed significant differences, including those involving the most distant Pacific colony as well as among some Atlantic populations. Weak population differentiation following the model of isolation by distance in the little auk is similar to the patterns reported in other high-Arctic bird species, indicating that a lack of distinct genetic structure is a common phenomenon in the Arctic avifauna.  相似文献   

14.
The majority of specimens of the scallop Chlamys opercularis found in Strangford Lough, County Down, Ireland, are infected with a rare and exotic ciliate Licnophora auerbachii. The ciliate is found predominantly on the eyes of the scallop which (together with numerous tentacles) are borne by the middle marginal folds of the mantle. The ciliates are found attached to both the clear cornea covering the lens and also the surrounding pigmented iris, their large food vacuoles often containing black consistently sized granules, particles derived from the pigmented epithelial cells of the scallop eye. These cells are abraded from the surface of the iris and become detached due to the action of the basal disc of L. auerbachii during its clamping and locomotory activities on the eye surface. Scanning electron microscope observations show that the foot region of the ciliate exerts both a suction and abrasive action on the eye and leaves a distinct “footprint” on the eye surface in the form of a saucer-shaped depression. In many of the heavily infected scallops there was evidence of damage to the eyes with consequent loss of pigment and in some instances surface distortion of the eye itself.  相似文献   

15.
The major urinary protein (MUP) complex of normal inbred laboratory mice (Mus musculus musculus) is a family of three electrophoretically distinguishable components, designated 1, 2, and 3 in order of increasing anodal mobility at pH 5.5. Components 1 and 2 are under the control of a single genetic locus; the MUP complex of a given inbred strain consists of component 1 or 2 plus component 3. In this study, the urinary protein of two subspecies of Asian wild mice, Mus musculus molossinus (originally trapped in Japan) and Mus musculus castaneus (originally trapped in Thailand), was examined electrophoretically and ultracentrifugally. The MUP complex of male M. m. molossinus and M. m. castaneus sedimented at approximately the same rate as that of M. m. musculus (s 20 =2.0?2.2S). It consisted of a “fast” (i.e., more anodal than component 3) and an “intermediate” component plus one or more “origin” (i.e., less anodal than component 1) components. The “fast” and “origin” components were isolated chromatographically, and NH2-terminal sequences spanning the first 36 residues were determined. Comparison with the NH2-terminal sequences determined for components 1, 2, and 3 isolated from the urine of BALB/c or C57BL/6 mice revealed, except for a single replacement at position 6 in the “origin” component of M. m. molossinus, no differences among the 1, 2, “origin”, and “fast” components. Component 3 was highly homologous but differed from component 1 at nine positions; its residue at position 6 was the same as that of the M. m. molossinus “origin” component.  相似文献   

16.
A mixture of C28 and C29 sterols have been isolated from Leptosphaeria typhae grown in vitro on “oat water” and characterized by GLC and MS. Mono-, di- and tri-unsaturated sterols are present in the extracts of fungi cultivated both in the dark and in the light but the sterol composition is different. The influence of “oat water” on sterol structure has been determined by comparison with the sterols of the same fungus grown on synthetic medium in the dark.  相似文献   

17.
B型烟粉虱对寄主转换的适应性   总被引:1,自引:0,他引:1  
周福才  李传明  顾爱祥  王萍  任佳 《生态学报》2011,31(21):6505-6512
将B型烟粉虱分别从嗜性较强的番茄上转移到嗜性相对较弱的国抗22棉花、泗棉3号棉花和辣椒上, 以及从嗜性较弱的辣椒上转移到嗜性相对较强的番茄、国抗22棉花和泗棉3号棉花上, 观察寄主转移后的F1代、F2代、F3代烟粉虱产卵效应和寄主适应度的变化;将F4代烟粉虱再转移到原寄主, 观察烟粉虱产卵效应和寄主适应度的恢复情况。结果表明, 烟粉虱在不同嗜性寄主上的产卵效应存在明显的差异。在不同嗜性的寄主之间转移, 烟粉虱的寄主适应度变化趋势不同, 从嗜性较强的寄主转移到嗜好性相对较弱的寄主上, 烟粉虱的寄主适应度迅速下降;从嗜性较弱的寄主向嗜性较强的寄主转移后, 烟粉虱的适应度则会迅速提高。烟粉虱对新寄主的适应速度与其对原寄主和新寄主之间的嗜性差异程度有关, 但一般经过1-2个世代后, 产卵效应会逐渐恢复到烟粉虱在该寄主上的正常水平。从过渡寄主转移到原寄主, 烟粉虱的寄主适应度变化符合一般的寄主转移规律, 但嗜性相对较强的过渡寄主可以刺激烟粉虱提高寄主适应性。  相似文献   

18.
A modification of the method of rearing Ixodes ricinus gave a successful method of producing and reliably rearing adequate numbers of this tick for experimental work.Experiments on transmission of Babesia divergens by I. ricinus showed that infections could be initiated only in the adult stage of the tick. Whilst all stages of the F1 generation of an infected female could transmit infection, larvae and nymphs could not acquire it. Infection persisted throughout the F1 generation and sometimes up to the F2 larval stage even when the ticks were maintained on hosts not susceptible to B. divergens. Both parasitaemic and premune carrier hosts were infective to ticks. A single infected adult or nymph could transmit infection.  相似文献   

19.
An alternative to recent interpretations of locomotor and postural behaviour in Dryopithecus (Proconsul) africanus as characteristic of “brachiating” or “knuckle-walking” adaptations is suggested. Analysis of the available joint complexes of the D. africanus upper limb and consideration of criteria employed by some researchers demonstrate that reconstruction of positional behaviour in Miocene Hominoidea is extremely speculative. However, the direction and range of movement within the elbow and wrist complexes of D. africanus can be defined with reference to available articular surfaces. Movement capabilities were apparently similar to those of quadrupedal, palmigrade primates.  相似文献   

20.
Gelidium elegans Kützing is commonly found in Korea, China, and Japan, and is the economically most important agarophyte in the northwest Pacific. To assess the genetic structure of the Korean species, we analyzed 1200 base pairs of the mitochondrial cox1 gene from 272 individuals collected from 36 locations. A total of 34 haplotypes were found, most of which were unique, including 27 (79%) ‘private’ haplotypes. The nucleotide and haplotype diversities of cox1 within G. elegans were 0.711 ± 0.028 (H) and 0.00736 ± 0.00038 (π), respectively. The distribution of cox1 haplotypes, pairwise FST values, results of neutrality tests, AMOVA, and mismatch distribution revealed the existence of a deep genetic break between central Pacific Japan and all the other locations, corresponding to the surface seawater current patterns as well as the genetic signature of potential demographic expansion.  相似文献   

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