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1.
Hans Löhrl 《Journal of Ornithology》1981,122(2):173-180
Zusammenfassung Die den Lorbeerwald bewohnende KanarentaubeColumba bollii ist entgegen manchen Befürchtungen auf Teneriffa noch nicht ausgestorben. Sie bewohnt noch schwer zugängliche Schluchten im Nordosten der Insel. Nur verstärkter Schutz kann sie vor dem Aussterben retten.Die LorbeertaubeColumba junoniae, bisher nur aus La Palma und Gomera bekannt, kommt auch in geringer Zahl auf Teneriffa vor.
Two extremely endangered Pigeons of the laurel forest,Columba bollii andC. junoniae, on Tenerife
Summary The Bolle's PigeonColumba bollii which lives in laurel forests is, despite many fears, not yet extinct on Tenerife. It still inhabits wooded crevices in the North-East of the island which are virtually inaccessible. Only increased protection can it save from extinction.The Laurel PigeonColumba junoniae, until now only known from La Palma and Gomera, is also present in small number on Tenerife.相似文献
2.
Parallelisms and paraphyletic assemblages are common among ovenbirds. Molecular markers are therefore the best approach when
studying the evolutionary relationships among the members of this unparalleled diversified family. We obtained nucleotide
sequence data from mitochondrial (cytochrome b) and nuclear genes (myoglobin and glyceraldehyde-3-phosphodehydrogenase) and used these to deduce the phylogenetic position
of a monotypic genus endemic to the austral temperate rainforests of southern South America, the Des Murs’ Wiretail (Sylviorthorhynchus
desmursii Des Murs, 1847, Aves: Furnariidae). Phylogenetic analyses based on maximum parsimony, maximum likelihood and Bayesian inference
all converged into a congruent topology, with a basal position of Des Murs’ Wiretail within Synallaxinae together with Tit–Spinetails
(Leptasthenura). Our data reject the hypothesis of a phylogenetic relationship between Des Murs’ Wiretail and thistletails (Schizoeaca) which exhibit parallelisms in morphology, tail structure and nest architecture. Using a molecular clock based on the myoglobin
intron 2 gene, we estimated a divergence time of Des Murs’ Wiretail from Tit-Spinetails of 14–15 Myr, which is associated
with the appearance of sclerophyllous forest elements in Chile at the Middle–Upper Miocene.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
3.
Muhammad Arshad Javier Gonzalez Abdel Aziz El-Sayed Tim Osborne Michael Wink 《Journal of Ornithology》2009,150(2):419-430
Populations of Oriental White-backed Vulture (Gyps bengalensis) and Long-billed Vulture (Gyps indicus) dramatically declined by 95–100% on the Indian subcontinent in mid-1990s. The present study was conducted to discover the
phylogeny and phylogeography of Gyps species based on nuclear (recombination activating gene, RAG-1) and mitochondrial (cytochrome b, cytb) markers. Gyps species showed monophyly and no geographic partition was observed within the three groups of Gyps species (G. bengalensis, G. indicus and G. fulvus) despite the large sample size available (n = 149). Our study supports the treatment of G. indicus and G.
tenuirostris as separate species. In all analyses, the earliest divergence separated G. bengalensis from all other Gyps taxa while a sister relationship was supported between G. fulvus and G. rueppellii, and these two taxa together were sister group to a clade consisting of G. indicus, G. tenuirostris and G. coprotheres. Molecular clock estimates of both nuclear and mitochondrial (RAG-1, cytb) genes indicated a rapid and recent diversification within the Gyps 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 Order Zoantharia has long been taxonomically neglected primarily due to difficulty in examining the internal morphology
of sand-encrusted zoanthids. However, recent work using molecular markers has shown an unexpectedly high diversity of previously
“hidden” taxa (families and genera) within Zoantharia (=Zoanthidea, Zoanthiniaria). In this study, unidentified sediment-encrusting
zoanthid specimens (n = 8) were collected from living Japanese Red Coral Paracorallium japonicum (Family Coralliidae) during precious coral harvesting by Remotely Operated Vehicle (ROV) and manned submersible (February
2004–January 2006) at depths of 194–250 m at six locations between Ishigaki-jima Island and Kikai-jima Island, southern Japan.
DNA sequences (mitochondrial 16S ribosomal DNA [mt 16S rDNA], cytochrome oxidase subunit I [COI], nuclear internal transcribed
spacer of ribosomal DNA [ITS-rDNA]) unambiguously place these specimens in a previously undescribed, new monophyletic lineage
within the family Parazoanthidae. Corallizoanthus tsukaharai, gen. n. et sp. n. is the first reported zoanthid species associated with the family Coralliidae and unlike other described
gorgonian-associated zoanthids (Savalia spp.) does not secrete its own hard axis. Morphologically, C. tsukaharai sp. n. is characterized by generally unitary polyps and bright yellow external coloration.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Communicated by Biology Editor Dr Ruth Gates 相似文献
5.
Aswin Mangerich Harry Scherthan Jörg Diefenbach Ulrich Kloz Franciscus van der Hoeven Sascha Beneke Alexander Bürkle 《Transgenic research》2009,18(2):261-279
Here we report an approach to generate a knock-in mouse model using an ‘ends-out’ gene replacement vector to substitute the
murine Parp-1 (mParp-1) coding sequence (32 kb) with its human orthologous sequence (46 kb). Unexpectedly, examination of mutant ES cell clones
and mice revealed that site-specific homologous recombination was mimicked in three independently generated ES cell clones
by bidirectional extension of the vector homology arms using the endogenous mParp-1-flanking sequences as templates. This was followed by adjacent integration of the targeting vector, thus leaving the endogenous
mParp-1 locus functional. A related phenomenon termed ‘ectopic gene targeting’ has so far only been described for ‘ends-in’ integration-type
vectors in non-ES cell gene targeting. We provide reliable techniques to detect such ectopic gene targeting which represents
an unexpected caveat in mouse genetic engineering that should be considered in the design and validation strategy of future
gene knock-in approaches.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
6.
Yazawa R Yasuike M Leong J von Schalburg KR Cooper GA Beetz-Sargent M Robb A Davidson WS Jones SR Koop BF 《Marine biotechnology (New York, N.Y.)》2008,10(6):741-749
Nuclear deoxyribonucleic acid sequences from approximately 15,000 salmon louse expressed sequence tags (ESTs), the complete
mitochondrial genome (16,148bp) of salmon louse, and 16S ribosomal ribonucleic acid (rRNA) and cytochrome oxidase subunit
I (COI) genes from 68 salmon lice collected from Japan, Alaska, and western Canada support a Pacific lineage of Lepeophtheirus salmonis that is distinct from that occurring in the Atlantic Ocean. On average, nuclear genes are 3.2% different, the complete mitochondrial
genome is 7.1% different, and 16S rRNA and COI genes are 4.2% and 6.1% different, respectively. Reduced genetic diversity within the Pacific form of L. salmonis is consistent with an introduction into the Pacific from the Atlantic Ocean. The level of divergence is consistent with the
hypothesis that the Pacific form of L. salmonis coevolved with Pacific salmon (Onchorhynchus spp.) and the Atlantic form coevolved with Atlantic salmonids (Salmo spp.) independently for the last 2.5–11 million years. The level of genetic divergence coincides with the opportunity for
migration of fish between the Atlantic and Pacific Ocean basins via the Arctic Ocean with the opening of the Bering Strait,
approximately 5 million years ago. The genetic differences may help explain apparent differences in pathogenicity and environmental
sensitivity documented for the Atlantic and Pacific forms of L. salmonis.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
7.
8.
Jorge F. Toro-Vazquez Maritza Alonzo-Macias Elena Dibildox-Alvarado Miriam A. Charó-Alonso 《Food biophysics》2009,4(3):199-212
The effect of tripalmitin (TP) crystallization on the thermomechanical properties of organogels developed with candelilla
wax (CW) was investigated using safflower oil high in triolein (HOSFO) as the liquid phase. Factorial combinations of CW (i.e.,
0–3%) and TP (i.e., 0–1%) in the HOSFO were used to develop organogels at three different temperatures (T
set). The onset of crystallization (T
g) during the cooling stage (10 °C/min), the melting temperature (T
M), and the corresponding heat of melting (ΔH
M) of the organogels were determined by differential scanning calorimetry. Results showed that, without CW, the crystallization
of TP in the HOSFO at the concentrations and T
set investigated (i.e., −10 °C to 25 °C) did not develop a three-dimensional network that provided significant viscoelasticity
(i.e., solid-like behavior) to the HOSFO. The CW developed organogels in the HOSFO with T
M’s that increased from ≈30.5 °C up to ≈42.5 °C as a function of CW concentration. In contrast, in the CW–1% TP system, the
co-crystallization of TP and CW resulted in organogels with TM’s that varied just between 36 °C and 38 °C, independent of the CW concentration. Higher elastic modulus (G′) and yield stress
(σ*) were obtained with 3% CW–1.0% TP organogels than with organogels developed just by CW, particularly at T
set’s of −5 °C and 15 °C. This research showed that co-crystallization of TP and CW, occurring at different extent as a function
of T
set, resulted in organogels with thermomechanical properties different from the ones showed by CW organogels. The results showed
that co-crystallization of triacylglycerides with CW might be a useful alternative to tailor particular physicochemical properties
associated to a specific functionality (i.e., melting profile and texture). Organogelation of vegetable oil might be used
to develop trans-free vegetable-oil-based spreads and coatings and also novel food products with new textural perceptions for the consumers. 相似文献
9.
Quercus garryana habitats are increasingly being managed with prescribed fire, but acorn dependent wildlife might be adversely affected if
fires damage acorn crops. We examined one way that fire might affect subsequent acorn crops: through direct heating and damage
of buds containing the following year’s floral organs. We measured internal bud temperatures during controlled time and temperature
treatments, described damage to heated buds at the tissue and cellular levels and quantified spring flowering to assess the
consequences of the treatments. We found that internal bud temperature was logarithmically related to exposure time and linearly
related to treatment temperature. Tissue damage was more common in bud scales, staminate and bud scale scar primordia than
in leaf, pistillate, leaf axillary primordia and apical meristems. Damaged tissues were sequestered by cells with thickened
cell walls. A 133°C treatment applied for 60 s produced minimal damage or mortality, but damage increased rapidly in hotter
or longer treatments, culminating in 100% mortality at 273°C for 60 s. Our experiments account only for radiative, not convective
heating, but suggest that fires might produce sublethal effects that affect flowering and acorn crops. Q. garryana’s large buds possess an internal organ arrangement well suited to minimizing heat damage.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
10.
11.
Asian box turtles (genus Cuora, family Geoemydidae) comprise a clade of 12 aquatic and semiaquatic nominate species distributed across southern China and
Southeast Asia. Over the last two decades, turtles throughout Asia have been harvested at an unsustainable rate to satisfy
demands for food, traditional Chinese medicine, and the pet trade. Consequently, all species of Cuora were recently placed on the IUCN Red List, nine are currently listed as critically endangered by the IUCN, and all species
are listed in Appendix II of CITES. We compiled a 67-specimen mitochondrial (∼1,650 base pairs (bp) from two mitochondrial
genes) and a 40-specimen nuclear-plus-mitochondrial (∼3,900 bp total, three nuclear introns plus an additional ∼860 bp mitochondrial
gene fragment) DNA data set to reconstruct the phylogeny of Cuora species and to assess genetic diversity and species boundaries for several of the most problematic taxa. Our sampling included
23 C. trifasciata, 17 C. zhoui and 1–4 individuals of the remaining 10 species of Cuora. Maximum likelihood, maximum parsimony and Bayesian analyses all recovered similar, well resolved trees. Within the Cuora clade, mitochondrial and nuclear sequence data indicated that both C. zhoui and C. mccordi represent old lineages with little or no history of interspecific gene flow, suggesting that they are good genealogical species.
Based on mtDNA, Cuora pani was paraphyletic and C. trifasciata was composed of two highly divergent lineages that were not each other’s closest relatives; both cases of non-monophyly were
due to a mtDNA sequence that was widespread and identical in C. aurocapitata, C. pani and C. trifasciata. However, when combined with nuclear DNA results, our data indicate that C. trifasciata is a single, monophyletic taxon, and that mitochondrial introgression and nuclear-mitochondrial pseudogenes have led to a
complex pattern of mitochondrial gene relationships that does not reflect species-level histories. Our results imply that
captive “assurance colonies” of both C. trifasciata and C. pani should be genotyped to identify pure, non-hybrid members of both taxa, and we recommend that introgressed and pure taxa be
managed as independent entities until the full evolutionary histories of these critically endangered turtles are resolved. 相似文献
12.
Chloroplast DNA insertions into the nuclear genome of rice: the genes,sites and ages of insertion involved 总被引:1,自引:0,他引:1
Rice (Oryza sativa) is one of three predominant grain crops, and its nuclear and organelle genomes have been sequenced. Following genome analysis
revealed many exchanges of DNA sequences between the nuclear and organelle genomes. In this study, a total of 45 chloroplast
DNA insertions more than 2 kb in length were detected in rice nuclear genome. A homologous recombination mechanism is expected
for those chloroplast insertions with high similarity between their flanking sequences. Only five chloroplast insertions with
high sequence similarity between two flanking sequences from an insertion were found in the 45 insertions, suggesting that
rice might follow the non-homologous end-joining (NHEJ) repair of double-stranded breaks mechanism, which is suggested to
be common to all eukaryotes. Our studies indicate that the most chloroplast insertions occurred at a nuclear region characterized
by a sharp change of repetitive sequence density. One potential explanation is that regions such as this might be susceptible
target sites or “hotspots” of DNA damage. Our results also suggest that the insertion of retrotransposon elements or non-chloroplast
DNA into chloroplast DNA insertions may contribute significantly to their fragmentation process. Moreover, based on chloroplast
insertions in nuclear genomes of two subspecies (indica and japonica) of cultivated rice, our results strongly suggest that they diverged during 0.06–0.22 million years ago.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
13.
Sibylle Stoeckli Karsten Mody Andrea Patocchi Markus Kellerhals Silvia Dorn 《Tree Genetics & Genomes》2009,5(1):257-267
The aim of this study was to assess the genetic basis of rust mite (Aculus schlechtendali) resistance in apple (Malus × domestica). A. schlechtendali infestation of apple trees has increased as a consequence of reduced side effects of modern fungicides on rust mites. An
analysis of quantitative trait loci (QTLs) was carried out using linkage map data available for F1 progeny plants of the cultivars ‘Fiesta’ × ‘Discovery’. Apple trees representing 160 different genotypes were surveyed for
rust mite infestation, each at three different sites in two consecutive years. The distribution of rust mites on the individual
apple genotypes was aggregated and significantly affected by apple genotype and site. We identified two QTLs for A. schlechtendali resistance on linkage group 7 of ‘Fiesta’. The AFLP marker E35M42-0146 (20.2 cM) and the RAPD marker AE10-400 (45.8 cM) were
closest positioned to the QTLs and explained between 11.0% and 16.6% of the phenotypic variability. Additionally, putative
QTLs on the ‘Discovery’ chromosomes 4, 5 and 8 were detected. The SSR marker Hi03a10 identified to be associated to one of
the QTLs (AFLP marker E35M42-0146) was traced back in the ‘Fiesta’ pedigree to the apple cultivar ‘Wagener’. This marker may
facilitate the breeding of resistant apple cultivars by marker assisted selection. Furthermore, the genetic background of
rust mite resistance in existing cultivars can be evaluated by testing them for the identified SSR marker.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
14.
Sibylle Stoeckli Karsten Mody Cesare Gessler Andrea Patocchi Mauro Jermini Silvia Dorn 《Tree Genetics & Genomes》2008,4(4):833-847
The rosy apple aphid (Dysaphis plantaginea), the leaf-curling aphid (Dysaphis cf. devecta) and the green apple aphid (Aphis pomi) are widespread pest insects that reduce growth of leaves, fruits and shoots in apple (Malus × domestica). Aphid control in apple orchards is generally achieved by insecticides, but alternative management options like growing
resistant cultivars are needed for a more sustainable integrated pest management (IPM). A linkage map available for a segregating
F1-cross of the apple cultivars ‘Fiesta’ and ‘Discovery’ was used to investigate the genetic basis of resistance to aphids.
Aphid infestation and plant growth characteristics were repeatedly assessed for the same 160 apple genotypes in three different
environments and 2 consecutive years. We identified amplified fragment length polymorphism (AFLP) markers linked to quantitative
trait loci (QTLs) for resistance to D. plantaginea (‘Fiesta’ linkage group 17, locus 57.7, marker E33M35–0269; heritability: 28.3%), and to D. cf. devecta (‘Fiesta’ linkage group 7, locus 4.5, marker E32M39–0195; heritability: 50.2%). Interactions between aphid species, differences
in climatic conditions and the spatial distribution of aphid infestation were identified as possible factors impeding the
detection of QTLs. A pedigree analysis of simple sequence repeat (SSR) marker alleles closely associated with the QTL markers
revealed the presence of the alleles in other apple cultivars with reported aphid resistance (‘Wagener’, ‘Cox’s Orange Pippin’),
highlighting the genetic basis and also the potential for gene pyramiding of aphid resistance in apple. Finally, significant
QTLs for shoot length and stem diameter were identified, while there was no relationship between aphid resistance and plant
trait QTLs.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
15.
Joerns Fickel Heidi C. Hauffe Elena Pecchioli Ramon Soriguer Ljiljana Vapa Christian Pitra 《European Journal of Wildlife Research》2008,54(3):495-510
A substantial portion of today’s biodiversity is attributed to the climatic oscillations of the Pleistocene Ice Ages. Gradual
but dramatic climate changes were accompanied by expansion, contraction, and isolation of populations, promoting the accumulation
of genome differences and adaptations in refugial populations and resulting in allopatric differentiation in a variety of
taxa. In the present study, partial mitochondrial DNA sequences of the widely distributed European brown hare (Lepus europaeus) were analyzed to test whether the species’ present genetic structure is the result of postglacial re-colonization of Europe
from Asia Minor (clade A) and the Balkans (clade B) only, as suggested previously, or if additional refugia are likely. Analyses indicated the presence of an additional refugium
(Italy, clade I). The genealogic network of Italian hares displayed the tree-like structure expected from refugial populations, whereas central
European brown hare haplotypes revealed a clear star-phylogeny indicative of past-bottleneck population growth. This population
size expansion, which was confirmed by mismatch analysis, was estimated to have occurred ∼50–55 thousand years ago (kya).
The divergence of clade A* from the remaining matrilines is estimated at 239 kya, whereas the divergence of the ancestors of clades B* and I from A* occurred about 128 kya.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
16.
K. Praveen Karanth 《Journal of biosciences》2008,33(5):761-770
A recent phylogenetic study of langurs and leaf monkeys of South Asia suggested a reticulate evolution of capped and golden
leaf monkeys through ancient hybridization between Semnopithecus and Trachypithecus. To test this hybridization scenario, I analysed nuclear copies of the mitochondrial cytochrome b gene (numts) from capped, golden and Phayre’s leaf monkeys. These numts were aligned with mitochondrial cytochrome b sequences of various species belonging to the genera Semnopithecus and Trachypithecus. In the phylogenetic tree derived from this alignment, the numts fell into three distinct clades (A, B and C) suggesting
three independent integration events. Clade A was basal to Semnopithecus, and clades B and C were basal to Trachypithecus. Among the numts in clades A and C were sequences derived from species not represented in their respective sister mitochondrial
groups. This unusual placement of certain numts is taken as additional support for the hybridization scenario. Based on the
molecular dating of these integration events, hybridization is estimated to have occurred around 7.1 to 3.4 million years
ago. Capped and golden leaf monkeys might have to be assigned to a new genus to reconcile their unique evolutionary history.
Additionally, northeast India appears to be a ‘hot spot’ for lineages that might have evolved through reticulate evolution. 相似文献
17.
18.
Plant acyl-CoA dependent acyltransferases constitute a large specific protein superfamily, named BAHD. Using the conserved
sequence motifs of BAHD members, we searched the genome sequences of Populus and Arabidopsis, and identified, respectively, 94- and 61-putative genes. Subsequently, we analyzed the phylogeny, gene structure, and chromosomal
distribution of BAHD members of both species; then, we profiled expression patterns of BAHD genes by “in silico” northern- and microarray-analyses based on public databases, and by RT-PCR. While our genomic- and bioinformatic- analyses
provided full sets of BAHD superfamily genes, and cleaned up a few existing annotation errors, importantly it led to our recognizing
several unique Arabidopsis BAHD genes that inversely overlapped with their neighboring genes on the genome, and disclosing a potential natural anti-sense
regulation for gene expressions. Systemic gene-expression profiling of BAHD members revealed distinct tissue-specific/preferential
expression patterns, indicating their diverse biological functions. Our study affords a strong knowledge base for understanding
BAHD members’ evolutionary relationships and gene functions implicated in plant growth, development and metabolism.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
19.
Jaroslav Fulneček Roman Matyášek Aleš Kovařík 《Molecular genetics and genomics : MGG》2009,281(4):407-420
The widespread occurrence of epigenetic alterations in allopolyploid species deserves scrutiny that DNA methylation systems
may be perturbed by interspecies hybridization and polyploidization. Here we studied the genes involved in DNA methylation
in Nicotiana tabacum (tobacco) allotetraploid containing S and T genomes inherited from Nicotiana sylvestris and Nicotiana tomentosiformis progenitors. To determine the inheritance of DNA methyltransferase genes and their expression patterns we examined three
major DNA methyltransferase families (MET1, CMT3 and DRM) from tobacco and the progenitor species. Using Southern blot hybridization and PCR-based methods (genomic CAPS), we found
that the parental loci of these gene families are retained in tobacco. Homoeologous expression was found in all tissues examined
(leaf, root, flower) suggesting that DNA methyltransferase genes were probably not themselves targets of uniparental epigenetic
silencing for over thousands of generations of allotetraploid evolution. The level of CG and CHG methylation of selected high-copy
repeated sequences was similar and high in tobacco and its diploid progenitors. We speculate that natural selection might
favor additive expression of parental DNA methyltransferase genes maintaining high levels of DNA methylation in tobacco, which
has a repeat-rich heterochromatic genome.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under the accession numbers AM946602–AM946620
and FM872474–FM872476. 相似文献
20.
Jaewoo Yoon Shinya Kimura Jun-ichi Maruyama Katsuhiko Kitamoto 《Applied microbiology and biotechnology》2009,82(4):691-701
Aspergillus oryzae has received attention as a host for heterologous protein production. However, A. oryzae has 134 protease genes, which is recognized to be one of the major reasons for the proteolytic degradation of heterologously
produced proteins. We previously reported that double disruption of the protease genes (tppA and pepE) improved heterologous protein (human lysozyme) production by A. oryzae. In this study, we performed successive round of five protease genes (tppA, pepE, nptB, dppIV, and dppV) disruption in A. oryzae by pyrG marker recycling with highly efficient gene-targeting background (ΔligD). The multiple disruption of protease genes were confirmed by Southern blot analysis. Furthermore, the quintuple protease
gene disruptants showed the maximum production level of bovine chymosin (CHY) that was 34% higher than those of the double
protease gene disruptant (ΔtppA ΔpepE). Consequently, we successfully constructed a multiple protease gene disruptant bearing enhanced levels of CHY productivity.
We presented the first evidence that the quintuple disruption of the protease genes improved the production level of a heterologous
protein by A. oryzae.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献