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1.
Leaflet abscission in Sambucus nigra is the result of cell wall breakdown at the site of separation. Associated with wall degradation is an increase in the activity of the enzyme β1,4 glucanase (E.C.3.1.2.4) in the cells that comprise the abscission zone. The enzyme has been extracted from abscission zone tissue and purified using a substrate affinity column. A qualitative enzyme assay procedure has been developed and this has facilitated the purification process. The β1,4 glucanase enzyme has a pH optimum of 7 and a molecular mass of 54kDa. Antibodies have been raised to the purified protein. The role of the enzyme in the abscission process is discussed.  相似文献   

2.
We developed primers for eight polymorphic microsatellite loci in the endangered common hamster (Cricetus cricetus L.). Population genetic parameters were analysed on the basis of 70 adult individuals captured from a single population. Allele numbers per locus ranged from eight to 17. Expected and observed heterozygosities per locus ranged from 0.67 to 0.91 and from 0.41 to 0.8, respectively.  相似文献   

3.
L. Cheng  L. Liu  X. Yu  D. Wang  J. Tong 《Animal genetics》2010,41(2):191-198
Common carp (Cyprinus carpio) is an important fish for aquaculture, but genomics of this species is still in its infancy. In this study, a linkage map of common carp based on Amplified Fragment Length Polymorphism (AFLP) and microsatellite (SSR) markers has been generated using gynogenetic haploids. Of 926 markers genotyped, 151 (149 AFLPs, two SSRs) were distorted and eliminated from the linkage analyses. A total of 699 AFLP and 20 microsatellite (SSR) markers were assigned to the map, which comprised 64 linkage groups and covered 5506.9 cM Kosambi, with an average interval distance of 7.66 cM Kosambi. The normality tests on interval map distances showed a non‐normal marker distribution. Visual inspection of the map distance distribution histogram showed a cluster of interval map distances on the left side of the chart, which suggested the occurrence of AFLP marker clusters. On the other hand, the lack of an obvious cluster on the right side showed that there were a few big gaps which need more markers to bridge. The correlation analysis showed a highly significant relatedness between the length of linkage group and the number of markers, indicating that the AFLP markers in this map were randomly distributed among different linkage groups. This study is helpful for research into the common carp genome and for further studies of genetics and marker‐assisted breeding in this species.  相似文献   

4.
Freshly released pollen of black elderberry (Sambucus nigra L.) was incubated under various culture conditions until germination was achieved. Optimal conditions for germination were determined and used for maturation of unicellular microspores in vitro. Staining with 5-diphenyltetrazolium bromide, propidium iodide and iodine potassium iodide was used to assess pollen viability, nuclear phase and maturation, respectively. The germination rate was highest when fresh pollen was agitated at 40 rpm in Petri dishes containing a liquid medium consisting of Brewbaker and Kwack salts, 15% (w/v) sucrose, 500 mg/l MES sodium salt, at pH 5.0; germination reached nearly 70% after only 1 h in culture. Under these conditions, and with addition of 200 mg/l glutamine, 260 mg/l cytidine and 500 mg/l uridine, uninucleate microspores developed into mature pollen at a 12% germination rate. Our report is the first demonstration of maturation of S. nigra microspores in vitro.  相似文献   

5.
Todarodes pacificus is an important species for commercial fisheries, but its reproductive biology has been little understood. We isolated 11 polymorphic microsatellite loci from this species. These loci provided highly polymorphic microsatellite markers with four to 26 alleles per locus. The observed and expected heterozygosities ranged from 0.150 to 1.000, and from 0.660 to 0.974, respectively. These markers will be useful for research about the mating systems and genetic diversity of T. pacificus.  相似文献   

6.
Dalbergia nigra is an endangered tree restricted to the Brazilian Atlantic Forest. Ten polymorphic microsatellite loci were isolated and characterized in 47 trees from two populations. The total number of alleles per locus ranged from three to 12 alleles. The levels of observed and expected heterozygosities ranged from 0.304 to 0.740 and from 0.278 to 0.872, respectively. Significant deviations from Hardy-Weinberg were detected for only three loci in each population. No pair of loci exhibited significant linkage disequilibrium. These microsatellites provide an efficient tool to investigate genetic structure in forest remnants with the purpose of conservation of this species.  相似文献   

7.
The Point Arena mountain beaver (Aplodontia rufa nigra) is an endangered subspecies. Efforts to recover this sub‐species will be aided by advances in molecular genetics, specifically the ability to estimate population size using noninvasive genetic sampling. Here we report on the development of nine polymorphic loci for the Point Arena mountain beaver. These markers provide us sufficient power to distinguish individuals, and thus can be used for calculating population size and delineating population substructure.  相似文献   

8.
Differential screening of a cDNA library generated from RNA extracted from ethylene-treated leaflet abscission zones of Sambucus nigra resulted in the isolation of 20 abscission-related clones. These clones could be grouped into seven families. Sequencing of members of these families revealed that the majority encoded pathogenesis-related (PR) proteins, and these could be identified by sequence homology as a polyphenol oxidase (PPO), a PR-1 type protein, a Chial type chitinase, a PR-4 type protein similar to the potato win peptides, a PR-6 type proteinase inhibitor, a Chia4 type chitinase and a metallothionein-like protein (Coupe, Taylor & Roberts 1995, Planta 197, 442–447). Northern analysis revealed that these mRNAs were not expressed in freshly excised material but accumulated primarily in the abscission zone tissue after 18 h of exposure to ethylene at a time when abscission of the leaflet explants had reached 70%. Expression of the PPO and the Chia4-type chitinase was ethylene-dependent while that of the PR-4 type was up-regulated in the abscission zone tissue in the absence of the gas. The characterization of these mRNAs and their encoded proteins is presented and their possible roles during abscission are discussed.  相似文献   

9.
We describe a cost- and time-efficient method for designing new microsatellite markers in any species with substantial genomic DNA sequence data available. Using this technique, we report 14 new polymorphic dinucleotide microsatellite loci isolated from the common marmoset. The relative yield of new polymorphisms was higher with less labor than described in previous marmoset studies. Of 20 loci initially evaluated, 14 were polymorphic and amplified reliably (70% success rate). The number of alleles ranged from 3 to 9 with heterozygosity varying from 0.48 to 0.83.  相似文献   

10.
Ten polymorphic microsatellite loci were isolated and characterized for the ferruginous pygmy owl (Glaucidium brasilianum). Observed and expected heterozygosity were 0.07–0.85 and 0.1–0.88, respectively. Allele numbers ranged from five to 16 per locus.  相似文献   

11.
We isolated 13 polymorphic microsatellites from the red-tide causing dinoflagellate Akashiwo sanguinea. These loci were highly variable, with between 2 and 10 alleles per locus, and estimated gene diversity ranging from 0.08 to 0.82. These loci have the potential to reveal genetic structure and estimate gene flow among A. sanguinea populations.  相似文献   

12.
In this project, the uptake mechanisms and localization of two lectins from Sambucus nigra, further referred to as S. nigra agglutinin (SNA)‐I and SNA‐II, into insect midgut CF‐203 cells were studied. SNA‐I is a chimeric lectin belonging to the class of ribosome‐inactivating proteins, whereas SNA‐II is a hololectin devoid of enzymatic activity. Internalization of the fluorescein isothiocyanate‐labeled lectin was investigated using confocal microscopy. Both lectins were internalized into the cytoplasm of CF‐203 cells at similar rates. Preexposure of the insect midgut cells to specific inhibitors of clathrin‐ and caveolae‐mediated endocytosis resulted in an inhibition of lectin uptake in CF‐203 cells and caspase‐induced cytotoxicity caused by SNA‐I and SNA‐II, confirming the involvement of both endocytosis pathways. Further studies demonstrated that the uptake mechanism(s) for both lectins required phosphoinositide 3‐kinases, but did not depend on the actin cytoskeleton. Since the hololectin SNA‐II apparently uses a similar endocytosis pathway as the chimerolectin SNA‐I, it can be concluded that the endocytosis process mainly relies on the carbohydrate‐binding activity of the lectins under investigation. © 2011 Wiley Periodicals, Inc.  相似文献   

13.
We isolated 56 common buzzard (Buteo buteo) microsatellite loci from (AC)n‐ and (AAAG)n‐enriched genomic libraries. Eleven loci were tested on 90 individuals from Eastern Westphalia in Germany, yielding two to 17 alleles per locus (average 5.7) and expected heterozygosities ranging from 0.11 to 0.93 (average 0.53). These highly variable microsatellite markers provide a powerful means for investigating population genetic diversity in the common buzzard, a little‐understood aspect of this widespread species.  相似文献   

14.
Multiplex polymerase chain reaction (PCR) technique has recently been applied to gain many advantages in molecular genetics. The present study focused on the development of 15 new microsatellite markers with multiplex PCR systems in ayu, Plecoglossus altivelis, an important freshwater fish in Japan. All loci were followed Mendelian inheritance in 27 F1 progeny except for the one locus. The number of alleles per locus ranged from nine to 44 and the observed heterozygosities ranged from 0.680 to 0.980 in 50 unrelated individuals. The results indicate that these new microsatellite markers are useful for studies of linkage mapping and population genetics for the species.  相似文献   

15.
Using an enrichment procedure, we have cloned microsatellite repeats from black poplar (Populus nigra L.) and developed primers for microsatellite marker analysis. Ten primer pairs, mostly for trinucleotide repeats, produced polymorphic fragments in P. nigra. Some of them also showed amplification in other poplar species. (P. deltoides, P. tricocarpa, P. tremula, P. tremuloides, P. candicans, P. lasiocarpa). The best six loci were tested on 23 P. nigra genotypes collected across Europe. The microsatellites produced up to 12 alleles per locus in this set, with observed heterozygosity between 0.32 and 0.91.  相似文献   

16.
We developed seven microsatellite loci in the common frog, Rana temporaria. There were between 2 and 27 alleles per locus and the expected heterozygosities ranged from 0.28 to 0.96 in a sample of frogs collected in the French Alps. Adding these seven markers to the 15 previously available microsatellite loci for this species should facilitate studies of genetic structure of Rana temporaria populations at a fine geographical scale.  相似文献   

17.
We isolated 15 polymorphic microsatellites from Cochlodinium polykrikoides. These loci provide a class of highly variable genetic markers, as the number of alleles ranged from two to 15, and the estimate of gene diversity was from 0.083 to 0.880 across the 15 microsatellites. We consider that these loci have a potential to reveal the genetic structure and gene flow among C. polykrikoides populations.  相似文献   

18.
We present a set of 35 chloroplast microsatellite primers for Eucalyptus. Ten of the microsatellites displayed intraspecific polymorphism, and identified nine haplotypes among 16 Eucalyptus globulus individuals. Primer conservation was high, with a polymerase chain reaction (PCR) success rate of 98% when tested on four other Eucalyptus species and seven additional myrtaceous genera. Chloroplast microsatellites have applications in phylogeographic studies, fingerprinting and progeny analysis.  相似文献   

19.
Nine microsatellite loci are isolated and characterized for the marine isopod Limnoria sp., a model invertebrate species for the study of connectivity of marine brooders with high potential of dispersal through rafting. Analysis of 35 individuals of one population revealed a mean number of alleles of 12.66 and mean expected heterozygosity of 0.83, indicating a high level of variability at most loci. These polymorphic microsatellite loci should be useful to the study of the geographical distribution of the genetic diversity of this species of Limnoria.  相似文献   

20.
The muskellunge (Esox masquinongy) is a valued fisheries species throughout its native range. Numerous studies have documented performance and phenotypic differences among muskellunge populations, but genetic markers for assessment have been lacking. We characterized 14 microsatellite loci and developed five multiplex polymerase chain reactions. Successful amplification of northern pike (Esox lucius) was observed for seven loci. These microsatellites will be useful for analysing population structure, performance characteristics of propagated strains, and helping to develop and monitor hatchery management guidelines for muskellunge.  相似文献   

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