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31.
32.
LINDA M. McINNES IAN R. DADOUR MEREDITH E. STEWART WILLIAM G. F. DITCHAM PETER MAWSON PETER B. S. SPENCER 《Molecular ecology resources》2005,5(3):504-506
Microsatellite loci were isolated from Carnaby's black cockatoo (Calyptorhynchus latirostris: Aves), a highly valued, endangered, and endemic species of bird from Western Australia. This study describes three dinucleotide and one tetranucleotide microsatellite loci for which the primers produced clear and polymorphic amplification patterns with between two and nine alleles and moderate levels of variability. Two additional dinucleotide markers which were monomorphic in the Carnaby's cockatoo were able to amplify and were polymorphic in two other species of black cockatoo, greatly increasing the utility of these markers. 相似文献
33.
Numerous data suggested that the pharmacological and biochemical properties of 5-hydroxytryptamine1A (5-HT1A) receptors exhibit some regional differences in the CNS, notably within the raphe nuclei compared with various forebrain areas (such as the hippocampus). This possibility has been further investigated in the dorsal raphe nucleus and two areas within the hippocampus, the dentate gyrus and the CA1 area, using the quantitative autoradiographic technique. The potencies of 5'-guanylylimidodiphosphate to inhibit the specific binding of 125I-Bolton-Hunter-8-methoxy-2-(N-propyl-N-propylamino)tetralin (125I-BH-8-MeO-N-PAT) to 5-HT1A sites and of N-ethylmaleimide to block these sites irreversibly were identical in the dorsal raphe nucleus and the hippocampal areas in rat brain sections. In contrast, slight but significant differences were noted in the pH dependence and pharmacological properties of 5-HT1A sites labeled by 125I-BH-8-MeO-N-PAT in these three regions. Similarly, heat denaturation experiments and tissue exposure to either phospholipase A2 or the alkylating agent 8-methoxy-2-(N-2'-chloropropyl,N-propyl)aminotetraline revealed regional differences in the properties of 5-HT1A sites. However, in most cases, the observed variations were of greater amplitude between the CA1 area and the dentate gyrus, where 5-HT1A sites are located postsynaptically, than between any one of these areas and the dorsal raphe nucleus where they act as (presynaptic) somatodendritic autoreceptors. These data further support that subtypes of 5-HT1A receptors probably exist in the rat brain, but this heterogeneity seems unrelated to the pre- or post-synaptic location of these receptors. 相似文献
34.
Daisuke Hirata Alexei V. Abramov Gennady F. Baryshnikov Ryuichi Masuda 《Biological journal of the Linnean Society. Linnean Society of London》2014,111(3):627-635
Sequence analyses of the complete brown bear, Ursus arctos, mitochondrial DNA (mtDNA) genome have detected scattered single nucleotide polymorphisms (SNPs) that define distinct mtDNA haplogroups in phylogeographical studies. The degraded DNA in historical samples, such as stuffed or excavated specimens, however, is often not suitable for sequence analyses. To address this problem, we developed an amplified product length polymorphism (APLP) analysis for mtDNA‐haplogrouping U. arctos specimens by detecting haplogroup‐specific SNPs. We verified the validity and utility of this method by analysing up to 170‐year‐old skin samples from U. arctos specimens collected widely across continental Eurasia. We detected some of the same haplogroups as those occurring in eastern Hokkaido (Japan) and eastern Alaska in continental Eurasia (the Altai and the Caucasus). Our results show that U. arctos in eastern Hokkaido and eastern Alaska descended from a common ancestor in continental Eurasia, and suggest that U. arctos occupied several refugia in southern Asia during the Last Glacial Maximum. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 111 , 627–635. 相似文献
35.
Relationships between rhizoplane and rhizosphere bacteria and verticillium wilt resistance in potato
Six cultivars and breeding lines of potato (Solanum tuberosum) differing in susceptibility to verticillium wilt caused by Verticillium dahliae were studied with respect to quantitative and qualitative differences in the bacterial flora of their soil and rhizosphere-rhizoplane. Although, no association was observed between the types of bacteria that inhabited the soil or roots of wilt resistant and susceptible cultivars, quantitative differences were evident. These differences provide the first direct evidence that potato genotypes can influence bacterial populations. Bacterial populations were 9–25-fold higher on roots than in the adjacent soil. As the plants aged, the total number of rootcolonizing bacteria increased between 15 and 245%. Pseudomonas spp. were the most abundant microbes in the soil and rhizosphere-rhizoplane. The bacteria antagonistic to V. dahliae in vitro were identified as members of the genera Bacillus, Pseudomonas, Flavobacterium, and Gluconobacter. A statistically significant trend was evident toward the association of antagonistic bacteria with the more resistant potato cultivars. 相似文献
36.
S. M. Kaeppler 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(3):384-392
The power to detect QTL using near-isogenic line (NIL) comparisons versus recombinant inbred (RI) populations was assessed.
The power to detect QTL was found to be generally greater when using RI populations than when using NIL contrasts. Power to
detect QTL with NIL contrasts never exceeded that of RI populations when the number of RI lines is maximized relative to replication
of lines for a given number of experimental units. The relative power of NIL contrasts is highest for traits with high heritability
and when a gain in precision is realized due to increased replication of entries. Although NIL populations are generally less
powerful than RI populations of similar size, some practical considerations may enhance the value of these materials. Availability
of NILs allows the genetic effect of a specific chromosome region to be determined by comparing two lines; all RI lines in
a population need to be rescored for each new trait even if the effect of a specific chromosome region is suspected. NIL comparisons
may allow genetic differences to be detected by visual inspection; genetic effects can only be expressed as means and variances
with recombinant inbred populations. In summary, RI populations generally, and in some cases, substantially, provide better
power for QTL detection than NIL comparisons. Practical considerations, however, indicate that many factors need to be considered
when choosing a population structure to meet an experimental objective.
Received: 12 December 1996 / Accepted: 21 March 1997 相似文献
37.
Strategies for signal amplification in nucleic acid detection 总被引:3,自引:0,他引:3
S. Calin Andras J. Brian Power Edward C. Cocking Michael R. Davey 《Molecular biotechnology》2001,19(1):29-44
Many aspects of molecular genetics necessitate the detection of nucleic acid sequences. Current approaches involving target
amplification (in situ PCR, Primed in situ Labeling, Self-Sustained Sequence Replication, Strand Displacement Amplification), probe amplification (Ligase Chain Reaction,
Padlock Probes, Rolling Circle Amplification) and signal amplification (Tyramide Signal Amplification, Branched DNA Amplification)
are summarized in the present review, together with their advantages and limitations. 相似文献
38.
Phenylketonuria (PKU) is a widespread autosome recessive hereditary disease caused by a deficiency of the liver enzyme phenylalanine
hydroxylase, which results in distortion of metabolism of phenylalanine and accumulation of toxic metabolites. The knowledge
of molecular bases of PKU is of a high social importance as it enables phenotypic correction of the disease in the case of
its early diagnostics. This disease is known to be associated with mutations in the phenylalanine hydroxylase gene, the distribution
and mutation spectrum having pronounced ethnic and regional features. We studied the spectrum of mutations in the phenylalanine
hydroxylase gene in a group of patients with PKU from the Novosibirsk region to reveal 10 missense point mutations, 1 mutation
in the splice donor site, and 1 microdeletion. For these mutations, most widely distributed in the region, we used straightforward
detection methods basing on the restriction fragment length polymorphism (RFLP), artificial constructed restriction sites
(ACRS) PCR, and denaturing gradient gel electrophoresis (DGGE). 相似文献
39.
We describe the development of DNA markers for the fungal pathogen of Eucalyptus, Cryphonectria cubensis. These markers originated from cloned intershort sequence repeat polymerase chain reactions, which enrich for medium to highly repetitive DNA sequences. In total, 10 markers were isolated, eight of which were polymorphic, and these can subsequently be applied to study populations of C. cubensis. 相似文献
40.
A 5.8S nuclear ribosomal RNA gene sequence database: applications to ecology and evolution 总被引:2,自引:0,他引:2
We compiled a 5.8S nuclear ribosomal gene sequence database for animals, plants, and fungi using both newly generated and GenBank sequences. We demonstrate the utility of this database as an internal check to determine whether the target organism and not a contaminant has been sequenced, as a diagnostic tool for ecologists and evolutionary biologists to determine the placement of asexual fungi within larger taxonomic groups, and as a tool to help identify fungi that form ectomycorrhizae. 相似文献