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1.
Variation of the cytochrome b gene fragment was examined in 27 flat-headed voles Alticola strelzowi from different parts of the species range. A total of 15 haplotypes were described, while the species as a whole was characterized by low levels of genetic differentiation and polymorphism. The haplotypes fell into three haplogroups, one of which corresponded to the subspecies A. s. strelzowi, and the other two, to A. s. desertorum. Based on different index values, the level of genetic polymorphism in the later subspecies was considered to be higher than in the first one. Phylogeographic analysis suggested post-glacial dispersal of flat-headed voles from a single refugium located in Western Altai. Using different techniques, relatively recent colonization of the Central Altai territory was demonstrated (subspecies A. s. strelzowi), which determined low level of genetic variation in this territory.  相似文献   

2.
Wang Z  Liu Z  Wu X  Yan W  Zeng Z 《Molecular biology reports》2012,39(3):3067-3071
The complementary sex determination (csd) gene is the primary gene determining the gender of honey bees (Apis spp). In this study we analyzed the polymorphism of csd gene in six Apis mellifera subspecies. The genomic region 3 of csd gene in these six A. mellifera was cloned, and identified. A total of 79 haplotypes were obtained from these six subspecies. Analysis showed that region 3 of csd gene has a high level of polymorphism in all the six A. mellifera subspecies. The A. m. anatolica subspecies has a slightly higher nucleotide diversity (π) than other subspecies, while the π values showed no significant difference among the other five subspecies. The phylogenetic tree showed that all the csd haplotypes from different A. mellifera subspecies are scattered throughout the tree, without forming six different clades. Population differentiation analysis showed that there are significant genetic differentiations among some of the subspecies. The NJ phylogenetic tree showed that the A. m. caucasica and A. m. carnica have the closest relationship, followed by A. m. ssp, A. m. ligustica, A. m. carpatica and A. m. anatolica that were gathered in the tree in turn.  相似文献   

3.
Defense behavior of three, free living giant (Megapis) honey bee subspecies, Apis laboriosa, A. dorsata dorsata and A. dorsata breviligula, was compared. Disturbed worker bees responded with characteristic dorso-ventral defense body twisting (DBT). Workers of A. laboriosa twisted the thorax by 55°, and the two other A. dorsata subspecies by about 10° more. A. laboriosa workers raised the tip of the abdomen by 90° and workers of the two other bee subspecies by about 20° higher. Differences in those traits were highly significant between A. laboriosa and both A. dorsata subspecies, but were not significant between those two subspecies. The whole cycle of DBT was the most vigorous in A. d. breviligula (0.11 s), and it was twice as vigorous as in A. d. dorsata (0.26 s) and trice as in A. laboriosa (0.32 s). A. laboriosa twisted the body together with wings folded over the abdomen, while the two A. dorsata subspecies raised the abdomen between spread wings. This supports the opinion to treat A. laboriosa as a separate species. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

4.
The amago salmon, Oncorhynchus masou ishikawae, is an endemic subspecies of O. masou in Japan. Owing to the extensive stocking of hatchery fish throughout Japan, indigenous populations of O. m. ishikawae are now on the verge of extinction. We examined the genetic effects of stocking hatchery fish on wild populations in the River Koza, Japan, using microsatellite and mitochondrial DNA (mtDNA) markers. For mtDNA, haplotype mt1, which is common in wild populations, was present exclusively in isolated wild populations assumed to be unaffected by previous stocking, while it was never observed in hatchery fish. Genetic diversity was much higher in wild populations in the stocked area, which shared many mtDNA haplotypes with hatchery fish, than in isolated wild populations with haplotype mt1. Pairwise F ST estimates based on microsatellites showed significant differentiation among the isolated populations with many microsatellite loci monomorphic. Significant deviation from Hardy–Weinberg equilibrium was observed in wild populations in the area subject to stocking, where a Bayesian-based assignment test showed a high level of introgression with hatchery fish. These results suggest that wild populations with haplotype mt1, which became isolated through anthropogenic environmental change in the 1950–1960s, represent indigenous populations of O. m. ishikawae in the River Koza. They have low genetic diversity, most likely caused by genetic bottlenecks following damming and environmental deterioration, while stocking of hatchery fish over the past 30 years apparently had a large impact on the genetic structure of wild populations in the main channel of the River Koza.  相似文献   

5.
This study aimed at the indentification of the species and genotypes of the genus Crataegus in Syria and determination of the genetic relationships among them based on the analysis of genomic and chloroplast DNA (cpDNA) using ISSRs and CAPS techniques. Morphological characterization carried out on 49 Crataegus samples collected from different geographical regions of Syria revealed four Crataegus species: momogyna, C. sinaica, C. aronia and C. azarolus. In the dendrogram constructed for those samples based on ISSRs (20 primers), all samples that belong to C. monogyna were clustered in one cluster. Samples of the other three species were overlaped in another cluster. Two samples of these were the most distant from all other samples in the dendrogram and were suggested to represent hybrid species or subspecies. When CAPS technique was applied on four Crataegus samples that represent the four suggested species using 22 cpDNA regions and 90 endonucleases, no polymorphism was detected neither in amplification products sizes nor in restriction profiles. The inability of detection of variation in cpDNA among species suggested can be attributed to the low level of evolution of the cpDNA in the genus, and to the possibility that some of these species are either subspecies or hybrids since the cpDNA is inherited through one parent only.  相似文献   

6.
The analysis of 135 mitochondrial D-loop sequences of the Iberian autochthonous red-legged partridge (Alectoris rufa) from wild population hunting bags from various locations and fowl runs in Spain yielded 37 different haplotypes. Among these, three haplotypes correspond to chukar partridges (Alectoris chukar), indicating genetic introgression from birds illegally introduced for restocking: three individuals carrying such haplotypes where found in natural populations, one appeared among those sampled on a mass reproduction farm and the remaining 10 in another fowl-run. The geographical origin of the contaminating chukar haplotypes could be assigned to the most easterly area of the chukar partridge geographical distribution in China. Molecular diversity parameters in the A. rufa samples indicate a considerable amount of genetic variation. ΦST showed significant differences among populations that are not explained by geographical distance alone. Particularly, one northern population (Palencia) shows a certain degree of genetic differentiation that could reflect a previously suggested subspecies division. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

7.
We describe a novel extension of the Genomic Matching Technique (GMT) that defines haplotypes of the mannose binding lectin (MBL) region in Zebrafish (D. rerio). Four ancestral haplotypes have been identified to date, with at least one of these demonstrating a significant increase in resistance to L. anguillarum. MBL activates the lectin pathway of the complement system and stimulates the development of the complement cascade and the Membrane Attack Complex. Polymorphisms in humans have been associated with increased susceptibility and severity to a number of pathogenic organisms. As teleosts have a relatively immature acquired immune system, polymorphisms within MBL and other innate defence genes are likely to be critical in defining their susceptibility/resistance to various pathogenic organisms. We report multiple copies of MBL-like genes in D. rerio, with up to three copies tightly linked within a cluster spanning ∼15 kb on chromosome 2. Genomic analysis suggests that duplication, retroviral insertion and possibly gene mutation and/or deletion have been key factors in the evolution of this cluster. Molecular analysis has revealed extensive polymorphism, including at least five distinct amplicons and haplospecific gene copy number variation. This study demonstrates polymorphism within a critical component of the teleost innate immune system. The polymorphisms and the haplotypes encoding the unique variants are likely to be informative in defining susceptibility/resistance to infectious agents commonly encountered within aquatic environments. Future investigations will define other important haplotypes and transfer the knowledge to other finfish species, thereby enabling selection of broodstock for the aquaculture industry. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

8.
Hippophae rhamnoides ssp. sinensis occurs mainly in the arid regions of northwest China. The wood stands of this subspecies play an important role in maintaining the local ecosystems in these regions. In addition, the genetic characteristics are essential to understand the historical range changes of this subspecies and its morphological differentiation with other subspecies. In this study, we developed nine microsatellite loci for this subspecies for the first time. We used the combining biotin capture method to enrich AG/CT/AC/GT/CG/GTG/CCA microsatellites. Twenty-six microsatellites were isolated from the enriching library and nine of them were found to be polymorphic through screening 12 distantly distributed individuals. The number of alleles per locus ranged from three to twelve and expected heterozygosity from 0.2659 to 0.4767, respectively. We further performed cross-priming tests in another subspecies and two congeneric species. These firstly isolated loci will provide a useful tool to investigate the genetic structure of this subspecies and its morphological differentiation from the other subspecies.  相似文献   

9.
The population structuring and low genetic diversity of the Manchurian zokor Myospalax psilurus Milne-Edwards, 1874, an East Asian endemic included in the Red List of Russia, were demonstrated. Two separate geographical groups differing in the level of their genetic diversity were found on the territory of the Primorskii krai. The subpopulation located closest to the main area of this species was determined as ancestral. A subspecies differentiation of the Primorskii krai and Transbaikal M. psilurus populations was shown, as was the monophyletic origin of M. psilurus and its high divergence from M. aspalax. The animals from northern localities are recommended for reintroduction in nature under species recovery programs in Primorskii krai.  相似文献   

10.
The mitochondrial cytochrome c oxidase subunit I gene sequence was recently developed for DNA barcoding of red algal species. We determined the 1245 base pairs of the gene from 27 taxa of an agar-producing species, Gracilaria vermiculophylla, and putative relatives and compared the results with rbcL data from the same species. A total of 392 positions (31.5%) were variable, 282 positions (22.6%) were parsimoniously informative, and average sequence divergence was 13% in an ingroup. Within G. vermiculophylla, pairwise divergence of the gene was variable up to 11 bp (0.9%). Seven recognized haplotypes of cox1 tended to be geographically related. In the aligned 1386 bp of rbcL, three haplotypes were recognized. These results suggest that cox1 is a valuable molecular marker within species and will be very useful in haplotype analyses.  相似文献   

11.
Genetic characterization of a wild-derived house mouse, Mus musculus, originally collected near Lake Balkhash in the Republic of Kazakhstan, was performed by examining protein polymorphisms and nucleotide sequences for the hemoglobin beta chain (HBB) subunits. Protein electrophoresis, which was performed on a cellulose-acetate plate, showed an independent mobility pattern representing a new, previously undiscovered haplotype. Neighbor-joining analyses of the HBB adult genes, i.e., HBB-T1 and HBB-T2, and the intergenic spacer region showed that the Lake Balkhash mouse possessed genomic components that were mixed from different haplotypes. Compared to the previously determined HBB haplotypes, d, p, and w1, the HBB-T1 gene and ca. 11 kb of the spacer region were most similar to the w1 haplotype; however, the remainder of the spacer region and the HBB-T2 gene were most similar to the d haplotype but may represent a still uncharacterized and divergent haplotype. The recombination event is predicted to have occurred 2.5 kb upstream of the HBB-T2 gene and may have occurred through intersubspecific hybridization between mice of the musculus subspecies group (with the w1 haplotype) and the castaneus subspecies group (with the d-like haplotype). Alternatively, an unknown subspecies group that is equidistantly divergent from each of these subspecies groups may have been involved. Our findings suggest reticulate evolution among the subspecies groups during the evolution of M. musculus.  相似文献   

12.
13.
In the US, clonal growth of Fallopia japonica, Fallopia sachalinensis and their hybrid Fallopia x bohemica (Polygonaceae) is prominent, yet sexual reproduction and hybridization contribute to the genetic complexity of swarms. The contribution to this diversity from multiple introductions is unknown. Using 800 bp of the non-coding chloroplast marker accD–rbcL, we compared 21 Japanese haplotypes with 46 US samples from 11 states, 2 Canadian samples, and 6 European samples from 4 countries, in order to investigate if there were repeated introductions from Asia. While most North American and all European haplotypes accessions in our collection matched a single widespread haplotype, we identified 8 other haplotypes. Three haplotypes of F. japonica (including the widespread haplotype) and one F. sachalinensis matched previously identified Japanese haplotypes, supporting the hypothesis of multiple introductions in the US. Five additional US haplotypes were detected once. Four of these differed from Japanese haplotypes by one single nucleotide polymorphism (SNP), possibly indicating a recent in situ change. The fifth haplotype represents a garden cultivar, which differed from all F. japonica haplotypes. It therefore appears that the US genetic diversity of these taxa has three sources: intra-specific reproduction, inter-specific reproduction, and multiple sources of introduction.  相似文献   

14.
Although mitochondrial DNA mapping of Varroa destructor revealed the presence of several haplotypes, only two of them (Korean and Japanese haplotypes) were capable to infest Apis mellifera populations. Even though the Korean haplotype is the only one that has been reported in Argentina, these conclusions were based on mites sampled in apiaries from a specific geographical place (Buenos Aires province). To study mites from several sites of Argentina could reveal the presence of the Japanese genotype, especially considering sites near to Brazil, where Japanese haplotype was already detected. The aim of this work was to study the genetic structure of V. destructor populations from apiaries located in various provinces of Argentina, in order to determine the presence of different haplotypes. The study was carried out between January 2006 and December 2009. Phoretic adult Varroa mites were collected from honey bee workers sampled from colonies of A. mellifera located in Entre Ríos, Buenos Aires, Corrientes, Río Negro, Santa Cruz and Neuquén provinces. Twenty female mites from each sampling site were used to carry out the genetic analysis. For DNA extraction a nondestructive method was used. DNA sequences were compared to Korean haplotype (AF106899) and Japanese haplotype (AF106897). All DNA sequences obtained from mite populations sampled in Argentina, share 98% of similitude with Korean Haplotype (AF106899). Taking into account these results, we are able to conclude that Korean haplotype is cosmopolite in Argentina.  相似文献   

15.
16.
Of the only known two Lagoon populations of Irrawaddy dolphins (Orcaella) in the world, one is residing in the Chilika Lagoon in Orissa state, India. In addition to accidental deaths in gill net fishery and mechanized boat operations, there has been exploitation of the species for their oil. Extreme patchy distribution and vulnerability to becoming entangled in fishing gear has made it a focus of conservation concern. Information on genetic diversity of populations has considerable potential for informing conservation plans. The present paper reports the first genetic study of O. brevirostris from Chilika Lagoon based on mtDNA sequencing and PCR-based sex identification from 11 individuals. Control region sequence comparison showed two haplotypes and cytochrome b a single haplotype in the Chilika population of the species. Phylogenetic analysis indicated distinct clades within the Asian samples, with the Indian population showing closest genetic proximity to the haplotypes from Thailand. Sex of the animal was determined by PCR-based method. It is important to continue to examine the population discreteness and genetic variation of Irrawaddy dolphin in Chilika Lagoon vis-à-vis its global geographic distribution for formulating the conservation plans of the species.  相似文献   

17.
Apodemus sylvaticus stankovici, described from the topographically rough landscape of the western Balkan glacial refugium, was recently proposed as being either a junior synonym of Apodemus flavicollis or a species on its own right. To untangle this taxonomic vagueness, we sequenced complete cytochrome b gene in 28 field mice collected at 12 locations in the mountains of Bosnia and Herzegovina, Montenegro, western Macedonia and northern Greece. Samples yielded 27 new haplotypes which clustered into two distinct groups. One of these clades also included the reference haplotype of A. flavicollis, while another cluster emerged as being identical with the reference sample for A. sylvaticus. As is common in Apodemus, both species retrieved in our analysis were characterized by low levels of intraspecific variation (0.4–0.9%) as opposed to a high level of differentiation between them (8.0–10.0%); therefore, the taxonomic classification of our material was without doubt. We found no evidence regarding the presence of an additional cryptic species in the mountains of the western Balkans. The very similar values of genetic variability in the two species imply their common evolutionary history of a long-term coexistence in the western Balkan refugium.  相似文献   

18.
Sinorhizobium meliloti natural populations show a high level of genetic polymorphism possibly due to the presence of mobile genetic elements such as insertion sequences (IS), transposons, and bacterial mobile introns. The analysis of the DNA sequence polymorphism of the nod region of S. meliloti pSymA megaplasmid in an Italian isolate led to the discovery of a new insertion sequence, ISRm31. ISRm31 is 2,803 bp long and has 22-bp-long terminal inverted repeat sequences, 8-bp direct repeat sequences generated by transposition, and three ORFs (A, B, C) coding for proteins of 124, 115, and 541 amino acids, respectively. ORF A and ORF C are significantly similar to members of the transposase family. Amino acid and nucleotide sequences indicate that ISRm31 is a member of the IS66 family. ISRm31 sequences were found in 30.5% of the Italian strains analyzed, and were also present in several collection strains of the Rhizobiaceae family, including S. meliloti strain 1021. Alignment of targets sites in the genome of strains carrying ISRm31 suggested that ISRm31 inserts randomly into S. meliloti genomes. Moreover, analysis of ISRm31 insertion sites revealed DNA sequences not present in the recently sequenced S. meliloti strain 1021 genome. In fact, ISRm31 was in some cases linked to DNA fragments homologous to sequences found in other rhizobia species.  相似文献   

19.
Using allozyme analysis, genetic and genotypic variation of rare relict species, a member of one of ancient angiosperm families, Araliaceae, the clonal plant Oplopanax elatus (Nakai) Nakai, was evaluated. Electrophoretic separation of the enzymes is described, and genetic interpretation of the enzymes variation patterns is presented. The values of genetic variation indices obtained were low (P = 25%; A = 1.45: H o = 0.131; H e = 0.113) and comparable with the data reported for the rare plant species and the representatives of the family Araliaceae. The main factors responsible for the polymorphism level observed might be the evolutionary history of the species and gene drift. The level of genotypic diversity (G/N = 0.76; D = 0.97) was substantially higher, compared to the values reported for species with vegetative reproduction (D = 0.62). These results suggest certain contribution of the propagation by seeds in the formation of the species of interest.  相似文献   

20.
This study demonstrates that self-compatible (SC) peach has mutant versions of S haplotypes that are present in self-incompatible (SI) Prunus species. All three peach S haplotypes, S 1 , S 2 , and S 2m , found in this study encode mutated pollen determinants, SFB, while only S 2m has a mutation that affects the function of the pistil determinant S-RNase. A cysteine residue in the C5 domain of the S 2m -RNase is substituted by a tyrosine residue, thereby reducing RNase stability. The peach SFB mutations are similar to the SFB mutations found in SC haplotypes of sweet cherry (P. avium) and Japanese apricot (P. mume). SFB 1 of the S 1 haplotype, a mutant version of almond (P. dulcis) S k haplotype, encodes truncated SFB due to a 155 bp insertion. SFB 2 of the S 2 and S 2m haplotypes, both of which are mutant versions of the S a haplotype in Japanese plum (P. salicina), encodes a truncated SFB due to a 5 bp insertion. Thus, regardless of the functionality of the pistil determinant, all three peach S haplotypes are SC haplotypes. Our finding that peach has mutant versions of S haplotypes that function in almond and Japanese plum, which are phylogenetically close and remote species, respectively, to peach in the subfamily Prunoideae of the Roasaceae, provides insight into the SC/SI evolution in Prunus. We discuss the significance of SC pollen part mutation in peach with special reference to possible differences in the SI mechanisms between Prunus and Solanaceae.  相似文献   

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